Malnutrition among vaccinated children aged 0-5 years in Batouri, Republic of Cameroon.

PubMed

Nagahori, Chikako; Kinjo, Yoshihide; Tchuani, Jean Paul; Yamauchi, Taro

2017-12-01

Malnutrition continues to contribute to a high infant mortality rate. This study aimed to determine the prevalence of malnutrition and its potential association with the time at which complementary feeding was introduced among children aged 0-5 years in Batouri, Republic of Cameroon. Mothers (n=212) were interviewed using a structured questionnaire. Child height or length, and weight measurements were determined and the appropriate Z -scores calculated. Multiple regression analysis was performed with the values of all nutritional status indicators as dependent variables and the time of commencing complementary feeding, and the child's age and sex, as independent variables. The prevalence of stunting (height/length for age<-2 standard deviation [SD]), underweight (weight for age<-2SD), and wasting (weight for height/length<-2SD) was 45.8%, 30.2%, and 11.3%, respectively. Even taking into consideration the biological variables, there was a significant association in the effects of time of starting complementary foods on the nutritional status indicators. Furthermore, adding socio-economic variables did not produce a rise in adjusted R 2 values for all age group models concerned. Approximately 30% of the children in the study region were underweight, and approximately half of the children exhibited stunting, indicating chronic malnutrition. Commencing complementary feeding at an appropriate time had a positive effect on nutritional status from approximately 2 years of age.

Developmental Pathways from Parental Socioeconomic Status to Adolescent Substance Use: Alternative and Complementary Reinforcement.

PubMed

Lee, Jungeun Olivia; Cho, Junhan; Yoon, Yoewon; Bello, Mariel S; Khoddam, Rubin; Leventhal, Adam M

2018-02-01

Although lower socioeconomic status has been linked to increased youth substance use, much less research has determined potential mechanisms explaining the association. The current longitudinal study tested whether alternative (i.e., pleasure gained from activities without any concurrent use of substances) and complementary (i.e., pleasure gained from activities in tandem with substance use) reinforcement mediate the link between lower socioeconomic status and youth substance use. Further, we tested whether alternative and complementary reinforcement and youth substance use gradually unfold over time and then intersect with one another in a cascading manner. Potential sex differences are also examined. Data were drawn from a longitudinal survey of substance use and mental health among high school students in Los Angeles. Data collection involved four semiannual assessment waves beginning in fall 2013 (N = 3395; M baseline age = 14.1; 47% Hispanic, 16.2% Asian, 16.1% multiethnic, 15.7% White, and 5% Black; 53.4% female). The results from a negative binomial path model suggested that lower parental socioeconomic status (i.e., lower parental education) was significantly related to an increased number of substances used by youth. The final path model revealed that the inverse association was statistically mediated by adolescents' diminished engagement in pleasurable substance-free activities (i.e., alternative reinforcers) and elevated engagement in pleasurable activities paired with substance use (i.e., complementary reinforcers). The direct effect of lower parental education on adolescent substance use was not statistically significant after accounting for the hypothesized mediating mechanisms. No sex differences were detected. Increasing access to and engagement in pleasant activities of high quality that do not need a reinforcement enhancer, such as substances, may be useful in interrupting the link between lower parental socioeconomic status and youth substance use.

Embryonic origin of mate choice in a lizard with temperature-dependent sex determination.

PubMed

Putz, Oliver; Crews, David

2006-01-01

Individual differences in the adult sexual behavior of vertebrates are rooted in the fetal environment. In the leopard gecko (Eublepharis macularius), a species with temperature-dependent sex determination (TSD), hatchling sex ratios differ between incubation temperatures, as does sexuality in same-sex animals. This variation can primarily be ascribed to the temperature having direct organizing actions on the brain. Here we demonstrate that embryonic temperature can affect adult mate choice in the leopard gecko. Given the simultaneous choice between two females from different incubation temperatures (30.0 and 34.0 degrees C), males from one incubation temperature (30.0 degrees C) preferred the female from 34.0 degrees C, while males from another incubation temperature (32.5 degrees C) preferred the female from 30.0 degrees C. We suggest that this difference in mate choice is due to an environmental influence on brain development leading to differential perception of opposite-sex individuals. This previously unrecognized modulator of adult mate choice lends further support to the view that mate choice is best understood in the context of an individual's entire life-history. Thus, sexual selection results from a combination of the female's as well as the male's life history. Female attractiveness and male choice therefore are complementary. Copyright 2005 Wiley Periodicals, Inc.

Physical and hormonal examination of Missouri River shovelnose sturgeon reproductive stage: A reference guide

USGS Publications Warehouse

Wildhaber, M.L.; Papoulias, D.M.; DeLonay, A.J.; Tillitt, D.E.; Bryan, J.L.; Annis, M.L.

2007-01-01

From May 2001 to June 2002 Wildhaber et al. (2005) conducted monthly sampling of Lower Missouri River shovelnose sturgeon (Scaphirhynchus platorynchus) to develop methods for determination of sex and the reproductive stage of sturgeons in the field. Shovelnose sturgeon were collected from the Missouri River and ultrasonic and endoscopic imagery and blood and gonadal tissue samples were taken. The full set of data was used to develop monthly reproductive stage profiles for S. platorynchus that could be compared to data collected on pallid sturgeon (Scaphirhynchus albus). This paper presents a comprehensive reference set of images, sex steroids, and vitellogenin (VTG, an egg protein precursor) data for assessing shovelnose sturgeon sex and reproductive stage. This reference set includes ultrasonic, endoscopic, histologic, and internal images of male and female gonads of shovelnose sturgeon at each reproductive stage along with complementary data on average 17-β estradiol, 11-ketotestosterone, VTG, gonadosomatic index, and polarization index.

Genetic Mechanisms Leading to Sex Differences Across Common Diseases and Anthropometric Traits.

PubMed

Traglia, Michela; Bseiso, Dina; Gusev, Alexander; Adviento, Brigid; Park, Daniel S; Mefford, Joel A; Zaitlen, Noah; Weiss, Lauren A

2017-02-01

Common diseases often show sex differences in prevalence, onset, symptomology, treatment, or prognosis. Although studies have been performed to evaluate sex differences at specific SNP associations, this work aims to comprehensively survey a number of complex heritable diseases and anthropometric traits. Potential genetically encoded sex differences we investigated include differential genetic liability thresholds or distributions, gene-sex interaction at autosomal loci, major contribution of the X-chromosome, or gene-environment interactions reflected in genes responsive to androgens or estrogens. Finally, we tested the overlap between sex-differential association with anthropometric traits and disease risk. We utilized complementary approaches of assessing GWAS association enrichment and SNP-based heritability estimation to explore explicit sex differences, as well as enrichment in sex-implicated functional categories. We do not find consistent increased genetic load in the lower-prevalence sex, or a disproportionate role for the X-chromosome in disease risk, despite sex-heterogeneity on the X for several traits. We find that all anthropometric traits show less than complete correlation between the genetic contribution to males and females, and find a convincing example of autosome-wide genome-sex interaction in multiple sclerosis (P = 1 × 10 -9 ). We also find some evidence for hormone-responsive gene enrichment, and striking evidence of the contribution of sex-differential anthropometric associations to common disease risk, implying that general mechanisms of sexual dimorphism determining secondary sex characteristics have shared effects on disease risk. Copyright © 2017 by the Genetics Society of America.

Genetic Mechanisms Leading to Sex Differences Across Common Diseases and Anthropometric Traits

PubMed Central

Traglia, Michela; Bseiso, Dina; Gusev, Alexander; Adviento, Brigid; Park, Daniel S.; Mefford, Joel A.; Zaitlen, Noah; Weiss, Lauren A.

2017-01-01

Common diseases often show sex differences in prevalence, onset, symptomology, treatment, or prognosis. Although studies have been performed to evaluate sex differences at specific SNP associations, this work aims to comprehensively survey a number of complex heritable diseases and anthropometric traits. Potential genetically encoded sex differences we investigated include differential genetic liability thresholds or distributions, gene–sex interaction at autosomal loci, major contribution of the X-chromosome, or gene–environment interactions reflected in genes responsive to androgens or estrogens. Finally, we tested the overlap between sex-differential association with anthropometric traits and disease risk. We utilized complementary approaches of assessing GWAS association enrichment and SNP-based heritability estimation to explore explicit sex differences, as well as enrichment in sex-implicated functional categories. We do not find consistent increased genetic load in the lower-prevalence sex, or a disproportionate role for the X-chromosome in disease risk, despite sex-heterogeneity on the X for several traits. We find that all anthropometric traits show less than complete correlation between the genetic contribution to males and females, and find a convincing example of autosome-wide genome-sex interaction in multiple sclerosis (P = 1 × 10−9). We also find some evidence for hormone-responsive gene enrichment, and striking evidence of the contribution of sex-differential anthropometric associations to common disease risk, implying that general mechanisms of sexual dimorphism determining secondary sex characteristics have shared effects on disease risk. PMID:27974502

Sex-specific mechanism of social hierarchy in mice.

PubMed

van den Berg, Wouter E; Lamballais, Sander; Kushner, Steven A

2015-05-01

The establishment of social hierarchies is a naturally occurring, evolutionarily conserved phenomenon with a well-established impact on fitness and health. Investigations of complex social group dynamics may offer novel opportunities for translational studies of autism spectrum disorder. Here we describe a robust behavioral paradigm using an automated version of the tube test. Isogenic groups of male and female mice establish linear social hierarchies that remain highly stable for at least 14 days, the longest interval tested. Remarkably, however, their social strategy is sex-specific: females primarily utilize intrinsic attributes, whereas males are strongly influenced by prior social experience. Using both genetic and pharmacological manipulations, we identify testosterone as a critical sex-specific factor for determining which social strategy is used. Males inheriting a null mutation of the sex-determining region Y (Sry) gene used a similar social cognitive strategy as females. In contrast, females with transgenic expression of Sry utilized a typically male social strategy. Analogously, castration of males and testosterone supplementation of females yielded similar outcomes, with a reversal of their social cognitive strategy. Together, our results demonstrate a sex-specific mechanism underlying social hierarchy, in which both males and females retain the functional capacity to adapt their social strategy. More generally, we expect the automated tube test to provide an important complementary approach for both fundamental and translational studies of social behavior.

Complementary and Alternative Therapies as Treatment Approaches for Interstitial Cystitis

PubMed Central

Whitmore, Kristene E

2002-01-01

The management of interstitial cystitis (IC) is predominantly the reduction of the symptoms of frequency, urgency, and pain. Multimodal treatment approaches for IC are helpful in customizing therapy for individual patients. Complementary and alternative therapies are a quintessential addition to the therapeutic armamentarium and frequently include dietary modification, nutraceuticals, bladder training, neuromodulation, stress reduction, and sex therapy. Dietary modification involves elimination of bladder irritants, fluid regulation, and a bowel regimen. Nutraceuticals studied for the treatment of IC include calcium glycerophosphate, L-arginine, mucopolysaccharides, bioflavinoids, and Chinese herbs. Bladder training is effective after pain reduction. The neuromodulation of high-tone pelvic-floor muscle dysfunction is achieved with physical therapy and acupuncture. Stress reduction and sex therapy are best administered by a qualified stress manager and sex therapist. Multimodal, nonconventional management may add efficacy to the treatment of IC. PMID:16986031

Sex and Cognition.

ERIC Educational Resources Information Center

Kimura, Doreen

This book describes the major differences between men and women in cognitive or problem-solving abilities and discusses the possible biological contributions to such differences. The book argues that sex differences in cognitive patterns and in motor skills arose out of complementary evolutionary histories of men and women and that evidence for…

What should be the basis for compulsory and optional health insurance premiums? Opinions of Swiss doctors.

PubMed

Jannot, Anne-Sophie; Perneger, Thomas V

2014-02-04

Little is known about doctors' opinions on how to finance health services. In Switzerland, mandatory basic health insurance currently uses regional flat fees that are unrelated to health and ability to pay, and optional complementary insurance uses risk-based premiums. Our objective was to assess Swiss physicians' opinions on what should determine health insurance premiums. We surveyed doctors in the canton of Geneva, Switzerland, about the desirable funding mechanism for mandatory health insurance and complementary health insurance. The proposed determinants of insurance premiums were current health and past medical history, lifestyle, healthcare costs in the previous year, genetic susceptibility to disease, regional average healthcare costs, household income, and wealth and demographic characteristics. Among the 1,516 respondents, only a few (<5%) believed that the mandatory health insurance premium should depend on health risk (health status, previous costs, genetics, and age and sex). More than 30% of respondents supported premiums based on lifestyle (34.6%), regional average health expenditures (31.2%), and household income and wealth (39.6%). For complementary health insurance, most respondents supported premiums based on lifestyle (74.6%) and on health risk (46.4%), but surprisingly also on household income and wealth (44.9%) and regional average health expenditures (39.4%). The characteristic most influencing the answers was the medical specialty. Doctors' opinions about healthcare financing mechanisms varied considerably, for both mandatory and complementary health insurance. Lifestyle was a surprisingly frequent choice, even though this criterion is not currently used in Switzerland. Ability to pay was not supported by the majority.

Similar but not the same: insights into the evolutionary history of paralogous sex-determining genes of the dwarf honey bee Apis florea.

PubMed

Biewer, M; Lechner, S; Hasselmann, M

2016-01-01

Studying the fate of duplicated genes provides informative insight into the evolutionary plasticity of biological pathways to which they belong. In the paralogous sex-determining genes complementary sex determiner (csd) and feminizer (fem) of honey bee species (genus Apis), only heterozygous csd initiates female development. Here, the full-length coding sequences of the genes csd and fem of the phylogenetically basal dwarf honey bee Apis florea are characterized. Compared with other Apis species, remarkable evolutionary changes in the formation and localization of a protein-interacting (coiled-coil) motif and in the amino acids coding for the csd characteristic hypervariable region (HVR) are observed. Furthermore, functionally different csd alleles were isolated as genomic fragments from a random population sample. In the predicted potential specifying domain (PSD), a high ratio of πN/πS=1.6 indicated positive selection, whereas signs of balancing selection, commonly found in other Apis species, are missing. Low nucleotide diversity on synonymous and genome-wide, non-coding sites as well as site frequency analyses indicated a strong impact of genetic drift in A. florea, likely linked to its biology. Along the evolutionary trajectory of ~30 million years of csd evolution, episodic diversifying selection seems to have acted differently among distinct Apis branches. Consistently low amino-acid differences within the PSD among pairs of functional heterozygous csd alleles indicate that the HVR is the most important region for determining allele specificity. We propose that in the early history of the lineage-specific fem duplication giving rise to csd in Apis, A. florea csd stands as a remarkable example for the plasticity of initial sex-determining signals.

Transcriptome profiling of Diachasmimorpha longicaudata towards useful molecular tools for population management.

PubMed

Mannino, M Constanza; Rivarola, Máximo; Scannapieco, Alejandra C; González, Sergio; Farber, Marisa; Cladera, Jorge L; Lanzavecchia, Silvia B

2016-10-12

Diachasmimorpha longicaudata (Hymenoptera: Braconidae) is a solitary parasitoid of Tephritidae (Diptera) fruit flies of economic importance currently being mass-reared in bio-factories and successfully used worldwide. A peculiar biological aspect of Hymenoptera is its haplo-diploid life cycle, where females (diploid) develop from fertilized eggs and males (haploid) from unfertilized eggs. Diploid males were described in many species and recently evidenced in D. longicaudata by mean of inbreeding studies. Sex determination in this parasitoid is based on the Complementary Sex Determination (CSD) system, with alleles from at least one locus involved in early steps of this pathway. Since limited information is available about genetics of this parasitoid species, a deeper analysis on D. longicaudata's genomics is required to provide molecular tools for achieving a more cost effective production under artificial rearing conditions. We report here the first transcriptome analysis of male-larvae, adult females and adult males of D. longicaudata using 454-pyrosequencing. A total of 469766 reads were analyzed and 8483 high-quality isotigs were assembled. After functional annotation, a total of 51686 unigenes were produced, from which, 7021 isotigs and 20227 singletons had at least one BLAST hit against the NCBI non-redundant protein database. A preliminary comparison of adult female and male evidenced that 98 transcripts showed differential expression profiles, with at least a 10-fold difference. Among the functionally annotated transcripts we detected four sequences potentially involved in sex determination and three homologues to two known genes involved in the sex determination cascade. Finally, a total of 4674SimpleSequence Repeats (SSRs) were in silico identified and characterized. The information obtained here will significantly contribute to the development of D. longicaudata functional genomics, genetics and population-based genome studies. Thousands of new microsatellite markers were identified as toolkits for population genetics analysis. The transcriptome characterized here is the starting point to elucidate the molecular bases of the sex determination mechanism in this species.

[Breastfeeding, complementary feeding and risk of childhood obesity].

PubMed

Sandoval Jurado, Luis; Jiménez Báez, María Valeria; Olivares Juárez, Sibli; de la Cruz Olvera, Tomas

2016-11-01

To evaluate the pattern of breastfeeding and weaning as a risk of obesity in pre-school children from a Primary Care Unit. Cross-sectional analytical study LOCATION: Cancun, Quintana Roo (Mexico). Children from 2-4 years of age from a Primary Care Unit. Duration of total and exclusive breastfeeding, age and food utilized for complementary feeding reported by the mother or career of the child and nutritional status assessment evaluated by body mass index (BMI) ≥ 95 percentile. Determination of prevalence ratio (PR), odds ratio (OR), chi squared (x2), and binary logistic regression. The study included 116 children (55.2% girls) with a mean age of 3.2 years, with obesity present in 62.1%, Exclusive breastfeeding in 72.4% with mean duration of 2.3 months, and age at introducing solids foods was 5.0 months. There was a difference for breastfeeding and complementary feeding by gender sex (P<.05). A PR=3.9 (95% CI: 1.49-6.34) was calculated for exclusive breastfeeding and risk of obesity. The model showed no association between these variables and obesity in children CONCLUSIONS: Exclusive breastfeeding of less than three months is associated with almost 4 more times in obese children. There was a difference in age of complementary feeding, duration of breastfeeding, and formula milk consumption time for obese and non-obese children. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

An invasive social insect overcomes genetic load at the sex locus.

PubMed

Gloag, Rosalyn; Ding, Guiling; Christie, Joshua R; Buchmann, Gabriele; Beekman, Madeleine; Oldroyd, Benjamin P

2016-11-07

Some invasive hymenopteran social insects found new populations with very few reproductive individuals. This is despite the high cost of founder effects for such insects, which generally require heterozygosity at a single locus-the complementary sex determiner, csd-to develop as females. Individuals that are homozygous at csd develop as either infertile or subfertile diploid males or not at all. Furthermore, diploid males replace the female workers that are essential for colony function. Here we document how the Asian honey bee (Apis cerana) overcame the diploid male problem during its invasion of Australia. Natural selection prevented the loss of rare csd alleles due to genetic drift and corrected the skew in allele frequencies caused by founder effects to restore high average heterozygosity. Thus, balancing selection can alleviate the genetic load at csd imposed by severe bottlenecks, and so facilitate invasiveness.

The Sex Determination Gene Shows No Founder Effect in the Giant Honey Bee, Apis dorsata

PubMed Central

Yan, Wei Yu; Wu, Xiao Bo; Zeng, Zhi Jiang; Huang, Zachary Y.

2012-01-01

Background All honey bee species (Apis spp) share the same sex determination mechanism using the complementary sex determination (csd) gene. Only individuals heterogeneous at the csd allele develop into females, and the homozygous develop into diploid males, which do not survive. The honeybees are therefore under selection pressure to generate new csd alleles. Previous studies have shown that the csd gene is under balancing selection. We hypothesize that due to the long separation from the mainland of Hainan Island, China, that the giant honey bees (Apis dorsata) should show a founder effect for the csd gene, with many different alleles clustered together, and these would be absent on the mainland. Methodology/Principal Findings We sampled A. dorsata workers from both Hainan and Guangxi Provinces and then cloned and sequenced region 3 of the csd gene and constructed phylogenetic trees. We failed to find any clustering of the csd alleles according to their geographical origin, i.e. the Hainan and Guangxi samples did not form separate clades. Further analysis by including previously published csd sequences also failed to show any clade-forming in both the Philippines and Malaysia. Conclusions/Significance Results from this study and those from previous studies did not support the expectations of a founder effect. We conclude that because of the extremely high mating frequency of A. dorsata queens, a founder effect does not apply in this species. PMID:22511940

The sex determination gene shows no founder effect in the giant honey bee, Apis dorsata.

PubMed

Liu, Zhi Yong; Wang, Zi Long; Yan, Wei Yu; Wu, Xiao Bo; Zeng, Zhi Jiang; Huang, Zachary Y

2012-01-01

All honey bee species (Apis spp) share the same sex determination mechanism using the complementary sex determination (csd) gene. Only individuals heterogeneous at the csd allele develop into females, and the homozygous develop into diploid males, which do not survive. The honeybees are therefore under selection pressure to generate new csd alleles. Previous studies have shown that the csd gene is under balancing selection. We hypothesize that due to the long separation from the mainland of Hainan Island, China, that the giant honey bees (Apis dorsata) should show a founder effect for the csd gene, with many different alleles clustered together, and these would be absent on the mainland. We sampled A. dorsata workers from both Hainan and Guangxi Provinces and then cloned and sequenced region 3 of the csd gene and constructed phylogenetic trees. We failed to find any clustering of the csd alleles according to their geographical origin, i.e. the Hainan and Guangxi samples did not form separate clades. Further analysis by including previously published csd sequences also failed to show any clade-forming in both the Philippines and Malaysia. Results from this study and those from previous studies did not support the expectations of a founder effect. We conclude that because of the extremely high mating frequency of A. dorsata queens, a founder effect does not apply in this species.

Pathway-based analysis of GWAs data identifies association of sex determination genes with susceptibility to testicular germ cell tumors.

PubMed

Koster, Roelof; Mitra, Nandita; D'Andrea, Kurt; Vardhanabhuti, Saran; Chung, Charles C; Wang, Zhaoming; Loren Erickson, R; Vaughn, David J; Litchfield, Kevin; Rahman, Nazneen; Greene, Mark H; McGlynn, Katherine A; Turnbull, Clare; Chanock, Stephen J; Nathanson, Katherine L; Kanetsky, Peter A

2014-11-15

Genome-wide association (GWA) studies of testicular germ cell tumor (TGCT) have identified 18 susceptibility loci, some containing genes encoding proteins important in male germ cell development. Deletions of one of these genes, DMRT1, lead to male-to-female sex reversal and are associated with development of gonadoblastoma. To further explore genetic association with TGCT, we undertook a pathway-based analysis of SNP marker associations in the Penn GWAs (349 TGCT cases and 919 controls). We analyzed a custom-built sex determination gene set consisting of 32 genes using three different methods of pathway-based analysis. The sex determination gene set ranked highly compared with canonical gene sets, and it was associated with TGCT (FDRG = 2.28 × 10(-5), FDRM = 0.014 and FDRI = 0.008 for Gene Set Analysis-SNP (GSA-SNP), Meta-Analysis Gene Set Enrichment of Variant Associations (MAGENTA) and Improved Gene Set Enrichment Analysis for Genome-wide Association Study (i-GSEA4GWAS) analysis, respectively). The association remained after removal of DMRT1 from the gene set (FDRG = 0.0002, FDRM = 0.055 and FDRI = 0.009). Using data from the NCI GWA scan (582 TGCT cases and 1056 controls) and UK scan (986 TGCT cases and 4946 controls), we replicated these findings (NCI: FDRG = 0.006, FDRM = 0.014, FDRI = 0.033, and UK: FDRG = 1.04 × 10(-6), FDRM = 0.016, FDRI = 0.025). After removal of DMRT1 from the gene set, the sex determination gene set remains associated with TGCT in the NCI (FDRG = 0.039, FDRM = 0.050 and FDRI = 0.055) and UK scans (FDRG = 3.00 × 10(-5), FDRM = 0.056 and FDRI = 0.044). With the exception of DMRT1, genes in the sex determination gene set have not previously been identified as TGCT susceptibility loci in these GWA scans, demonstrating the complementary nature of a pathway-based approach for genome-wide analysis of TGCT. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sex differences in opioid use and medical issues during buprenorphine/naloxone treatment.

PubMed

Barbosa-Leiker, Celestina; McPherson, Sterling; Layton, Matthew E; Burduli, Ekaterina; Roll, John M; Ling, Walter

2018-01-01

There are sex differences in buprenorphine/naloxone clinical trials for opioid use. While women have fewer opioid-positive urine samples, relative to men, a significant decrease in opioid-positive samples was found during treatment for men, but not women. In order to inform sex-based approaches to improve treatment outcomes, research is needed to determine if opioid use, and predictors of opioid use, differs between men and women during treatment. To test for sex differences in opioid use during a buprenorphine/naloxone clinical trial and determine if sex differences exist in the associations between addiction-related problem areas and opioid use over the course of the trial. This secondary data analysis of the National Drug Abuse Treatment Clinical Trials Network (CTN) 0003 examined sex differences (men = 347, women = 169) in opioid-positive samples in a randomized clinical trial comparing 7-day vs. 28-day buprenorphine/naloxone tapering strategies. Addiction-related problem areas were defined by Addiction Severity-Lite (ASI-L) domain composite scores. Women were more likely than men to use opioids during the course of the buprenorphine/naloxone clinical trial (B = .33, p = .01) and medical issues were positively related to submitting an opioid-positive sample during treatment for women (B = 1.67, p = .01). No ASI-L domain composite score was associated with opioid-positive samples during treatment for men. Women were more likely than men to use opioids during the course of the buprenorphine/naloxone clinical trial, and medical issues predicted opioid use during treatment for women but not men. Complementary treatment for medical problems during opioid replacement therapy may benefit women.

Contagious parthenogenesis, automixis, and a sex determination meltdown.

PubMed

Engelstädter, Jan; Sandrock, Christoph; Vorburger, Christoph

2011-02-01

Because of the twofold cost of sex, genes conferring asexual reproduction are expected to spread rapidly in sexual populations. However, in reality this simple prediction is often confounded by several complications observed in natural systems. Motivated by recent findings in the Cape honey bee and in the parasitoid wasp Lysiphlebus fabarum, we explore through mathematical models the spread of a recessive, parthenogenesis inducing allele in a haplodiploid population. The focus of these models is on the intricate interactions between the mode of parthenogenesis induction through automixis and complementary sex determination (CSD) systems. These interactions may result in asexual production of diploid male offspring and the spread of the parthenogenesis-inducing allele through these males. We demonstrate that if parthenogenetic females produce a substantial proportion of male offspring, this may prevent the parthenogenesis-inducing allele from spreading. However, this effect is weakened if these diploid males are at least partially fertile. We also predict a degradation of multilocus CSD systems during the spread of parthenogenesis, following which only a single polymorphic CSD locus is maintained. Finally, based on empirical parameter estimates from L. fabarum we predict that male production in parthenogens is unlikely to prevent the eventual loss of sexual reproduction in this system. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

An ensemble of dissimilarity based classifiers for Mackerel gender determination

NASA Astrophysics Data System (ADS)

Blanco, A.; Rodriguez, R.; Martinez-Maranon, I.

2014-03-01

Mackerel is an infravalored fish captured by European fishing vessels. A manner to add value to this specie can be achieved by trying to classify it attending to its sex. Colour measurements were performed on Mackerel females and males (fresh and defrozen) extracted gonads to obtain differences between sexes. Several linear and non linear classifiers such as Support Vector Machines (SVM), k Nearest Neighbors (k-NN) or Diagonal Linear Discriminant Analysis (DLDA) can been applied to this problem. However, theyare usually based on Euclidean distances that fail to reflect accurately the sample proximities. Classifiers based on non-Euclidean dissimilarities misclassify a different set of patterns. We combine different kind of dissimilarity based classifiers. The diversity is induced considering a set of complementary dissimilarities for each model. The experimental results suggest that our algorithm helps to improve classifiers based on a single dissimilarity.

Discursive Silences: Using Critical Linguistic and Qualitative Analysis to Explore the Continued Absence of Pleasure in Sex and Relationships Education in England

ERIC Educational Resources Information Center

Sundaram, Vanita; Sauntson, Helen

2016-01-01

In this paper, we present an analysis of "pleasure" in sex and relationships education (SRE) in England. Drawing together two distinct sources of data and different but complementary analytical frameworks, we argue that pleasure is largely absent within SRE and that this discursive silence serves to produce highly gendered and…

Negotiation for safer sex among married women in Cambodia: the role of women's autonomy.

PubMed

Ung, Mengieng; Boateng, Godfred O; Armah, Frederick A; Amoyaw, Jonathan A; Luginaah, Isaac; Kuuire, Vincent

2014-01-01

Negotiating safer sex among married women has been identified as an important determinant of vulnerability or resilience to new HIV infections. Using the Cambodia Demographic and Health Survey data of 2010, this paper examined negotiation for safer sex among 11,218 married women in the context of Cambodia's highly touted reduction in HIV/AIDS prevalence. The results from a complementary log-log regression model indicate that wealthier and highly educated married women were more likely to report that they can refuse sexual intercourse and ask their husbands to use a condom. Interestingly, while women who were fully involved in decision-making on their own health care were 19% more likely to refuse sex, they were 14% less likely to be able to ask their husbands to use a condom, compared with their counterparts who were not involved in this decision-making. Women who were partially involved in decision-making on family visits were 17% less likely to be able to ask their husbands to use a condom compared with those who were not involved. In this context, involvement in decision-making may have translated into trust and risk compensation. Those who believed in HIV transmission myths were less likely to negotiate safer sex relative to their counterparts who did not hold such myths to be true. Women's ability to negotiate for safer sex is, therefore, a function of their autonomy in terms of their full participation in decision-making in health care, household expenditure and mobility. Policy implications of the capacity of women to negotiate for safer sex are delineated.

Evaluating Complementary and Alternative Therapies

MedlinePlus

... t Work Drug Information Resources Side Effects Dating, Sex, and Reproduction Advanced Cancer For Children For Teens For Young Adults For Older Adults Prevention and Healthy Living Cancer.Net Videos Coping With Cancer Research and Advocacy Survivorship Blog ...

Complementary and alternative medicine for multiple sclerosis.

PubMed

Schwarz, S; Knorr, C; Geiger, H; Flachenecker, P

2008-09-01

We analyzed characteristics, motivation, and effectiveness of complementary and alternative medicine in a large sample of people with multiple sclerosis. A 53-item survey was mailed to the members of the German Multiple Sclerosis Society, chapter of Baden-Wuerttemberg. Surveys of 1573 patients (48.5 +/- 11.7 years, 74% women, duration of illness 18.1 +/- 10.5 years) were analyzed. In comparison with conventional medicine, more patients displayed a positive attitude toward complementary and alternative medicine (44% vs 38%, P < 0.05), with 70% reporting lifetime use of at least one method. Among a wide variety of complementary and alternative medicine, diet modification (41%), Omega-3 fatty acids (37%), removal of amalgam fillings (28%), vitamins E (28%), B (36%), and C (28%), homeopathy (26%), and selenium (24%) were cited most frequently. Most respondents (69%) were satisfied with the effects of complementary and alternative medicine. Use of complementary and alternative medicine was associated with religiosity, functional independence, female sex, white-collar job, and higher education (P < 0.05). Compared with conventional therapies, complementary and alternative medicine rarely showed unwanted side effects (9% vs 59%, P < 0.00001). A total of 52% stated that the initial consultation with their physician lasted less than 15 min. To conclude, main reasons for the use of complementary and alternative medicine include the high rate of side effects and low levels of satisfaction with conventional treatments and brief patients/physicians contacts.

Complementary and alternative medicine use in Turkish children with epilepsy.

PubMed

Goker, Zeynep; Serin, Hepsen Mine; Hesapcioglu, Selma; Cakir, Murat; Sonmez, Fatma Müjgan

2012-12-01

We aimed to determine the prevalence, pattern of use, parental sources of information and adverse effects of complementary and alternative medicine (CAM) in children with epilepsy. Parents of children with epilepsy (n=305; mean age: 8.3±4.3 years) were interviewed with structured open and close-ended questionnaire. Patients were divided in two groups, CAM and non-CAM and compared using statistical tests. The use of CAM was detected in 22.6% of the patients (n=69). Prayer was the most commonly used therapy in 91.3% of children (n=63). Gender (p=0.032, [OR]: 0.5, 95%CI: 0.287-0.945) and resistance to antiepileptic drugs (p=0.005, [OR]: 3.4, 95%CI: 1.459-8.148) were found to be associated with CAM use. Parental use of CAMs to treat their children with epilepsy is not common in the Eastern Blacksea Region of Turkey. The research findings have demonstrated that patients' parents trust in their doctors. However, male sex and the presence of resistance of anti epileptics are potentially CAM predictors. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Lack of behavioural evidence for kin avoidance in mate choice in a hymenopteran parasitoid (Hymenoptera: Braconidae).

PubMed

Bourdais, D; Hance, T

2009-05-01

Mechanisms for inbreeding avoidance should be prevalent in insects that reproduce by arrhenotokous haplodiploidy because of the higher potential production of unviable diploid males in inbred matings. Few studies have focused on mating strategies in insect parasitoids and even less on kinship relationships during mate choice. In this study we tested avoidance of kin as mate in the parasitic wasp Aphidius matricariae (Hymenoptera: Braconidae) using an ethological approach. Key mating parameters, such as male wing fanning, latent period before genitalia contact and duration of copulation were measured. No evidence for kin avoidance in mate choice in both A. matricariae males and females was observed in our behaviour (no choice or choice tests) tests. This lack of ethological sib mating avoidance could be due to different factors such as sex determination rule different than the single locus complementary sex determination, making lower the proportion of diploid males in case of sib matings and thus its negative consequence. The existence of other inbreeding avoidance strategies and mechanisms that reduce the probability of 2 receptive relatives meeting in nature may be common, for example, inbred mating may be rare through differential dispersal, delayed maturation, or protandry.

Origin of a function by tandem gene duplication limits the evolutionary capability of its sister copy.

PubMed

Hasselmann, Martin; Lechner, Sarah; Schulte, Christina; Beye, Martin

2010-07-27

The most remarkable outcome of a gene duplication event is the evolution of a novel function. Little information exists on how the rise of a novel function affects the evolution of its paralogous sister gene copy, however. We studied the evolution of the feminizer (fem) gene from which the gene complementary sex determiner (csd) recently derived by tandem duplication within the honey bee (Apis) lineage. Previous studies showed that fem retained its sex determination function, whereas the rise of csd established a new primary signal of sex determination. We observed a specific reduction of nonsynonymous to synonymous substitution ratios in Apis to non-Apis fem. We found a contrasting pattern at two other genetically linked genes, suggesting that hitchhiking effects to csd, the locus under balancing selection, is not the cause of this evolutionary pattern. We also excluded higher synonymous substitution rates by relative rate testing. These results imply that stronger purifying selection is operating at the fem gene in the presence of csd. We propose that csd's new function interferes with the function of Fem protein, resulting in molecular constraints and limited evolvability of fem in the Apis lineage. Elevated silent nucleotide polymorphism in fem relative to the genome-wide average suggests that genetic linkage to the csd gene maintained more nucleotide variation in today's population. Our findings provide evidence that csd functionally and genetically interferes with fem, suggesting that a newly evolved gene and its functions can limit the evolutionary capability of other genes in the genome.

Disclosure of complementary health approaches among low income and racially diverse safety net patients with diabetes.

PubMed

Chao, M T; Handley, M A; Quan, J; Sarkar, U; Ratanawongsa, N; Schillinger, D

2015-11-01

Patient-provider communication about complementary health approaches can support diabetes self-management by minimizing risk and optimizing care. We sought to identify sociodemographic and communication factors associated with disclosure of complementary health approaches to providers by low-income patients with diabetes. We used data from San Francisco Health Plan's SMARTSteps Program, a trial of diabetes self-management support for low-income patients (n=278) through multilingual automated telephone support. Interviews collected use and disclosure of complementary health approaches in the prior month, patient-physician language concordance, and quality of communication. Among racially, linguistically diverse participants, half (47.8%) reported using complementary health practices (n=133), of whom 55.3% disclosed use to providers. Age, sex, race/ethnicity, nativity, education, income, and health literacy were not associated with disclosure. In adjusted analyses, disclosure was associated with language concordance (AOR=2.21, 95% CI: 1.05, 4.67), physicians' interpersonal communication scores (AOR=1.50, 95% CI: 1.03, 2.19), shared decision making (AOR=1.74, 95% CI: 1.33, 2.29), and explanatory-type communication (AOR=1.46, 95% CI: 1.03, 2.09). Safety net patients with diabetes commonly use complementary health approaches and disclose to providers with higher patient-rated quality of communication. Patient-provider language concordance and patient-centered communication can facilitate disclosure of complementary health approaches. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Television and sex-role acquisition. 1: Content.

PubMed

Durkin, K

1985-06-01

Television has earned considerable public and academic criticism in recent years for the alleged bias in its sex-role content. A fundamental concern of many critics is with the representation of male and female roles that confronts children. This paper reviews the evidence accumulating from numerous content analyses of both adult and children's television. Overall, the evidence confirms that there are marked differences in the ways the medium presents the sexes. These differences are both quantitative and qualitative but the general pattern at either level is to present males as dominant and females as nurturant and complementary. Some qualifications, exceptions and gaps in the literature are discussed. The paper is the first of a three-part review series of television and sex-role acquisition: the subsequent papers will review respectively the effects of sex-stereotyped TV content upon children and the prospects for counter-stereotyped programmes aiming to modify young viewers' beliefs and attitudes.

The erosion of sexual dimorphism: challenges to religion and religious ethics.

PubMed

Gudorf, C E

2001-01-01

Late modernity has been witnessing the erosion of the dimorphic sexual paradigm that, in both strong and weak forms, has characterized human history as we know it. Recent discoveries in biology and the social sciences have combined with altered patterns in human sexual behavior to raise critical new questions about the inherited paradigm. Religions of the West whose sacred texts, mythologies, and codes of behavior assume that maleness and femaleness are exclusive and complementary types of sexuality-each of which determines sexual identity, reproductive role, social role, and the sex of one's partner-increasingly must grapple with both theoretical evidence for and experiential evidence of polymorphous human sexuality. Inherited categories of dimorphic sexuality not only are challenged but become less and less intelligible.

Patterns and determinants of breastfeeding and complementary feeding practices in urban informal settlements, Nairobi Kenya

PubMed Central

2011-01-01

Background The World Health Organisation (WHO) recommends exclusive breastfeeding during the first six months of life for optimal growth, development and health. Breastfeeding should continue up to two years or more and nutritionally adequate, safe, and appropriately-fed complementary foods should be introduced at the age of six months to meet the evolving needs of the growing infant. Little evidence exists on breastfeeding and infant feeding practices in urban slums in sub-Saharan Africa. Our aim was to assess breastfeeding and infant feeding practices in Nairobi slums with reference to WHO recommendations. Methods Data from a longitudinal study conducted in two Nairobi slums are used. The study used information on the first year of life of 4299 children born between September 2006 and January 2010. All women who gave birth during this period were interviewed on breastfeeding and complementary feeding practices at recruitment and this information was updated twice, at four-monthly intervals. Cox proportional hazard analysis was used to determine factors associated with cessation of breastfeeding in infancy and early introduction of complementary foods. Results There was universal breastfeeding with almost all children (99%) having ever been breastfed. However, more than a third (37%) were not breastfed in the first hour following delivery, and 40% were given something to drink other than the mothers' breast milk within 3 days after delivery. About 85% of infants were still breastfeeding by the end of the 11th month. Exclusive breastfeeding for the first six months was rare as only about 2% of infants were exclusively breastfed for six months. Factors associated with sub-optimal infant breastfeeding and feeding practices in these settings include child's sex; perceived size at birth; mother's marital status, ethnicity; education level; family planning (pregnancy desirability); health seeking behaviour (place of delivery) and; neighbourhood (slum of residence). Conclusions The study indicates poor adherence to WHO recommendations for breastfeeding and infant feeding practices. Interventions and further research should pay attention to factors such as cultural practices, access to and utilization of health care facilities, child feeding education, and family planning. PMID:21615957

Patterns and determinants of breastfeeding and complementary feeding practices in urban informal settlements, Nairobi Kenya.

PubMed

Kimani-Murage, Elizabeth W; Madise, Nyovani J; Fotso, Jean-Christophe; Kyobutungi, Catherine; Mutua, Martin K; Gitau, Tabither M; Yatich, Nelly

2011-05-26

The World Health Organisation (WHO) recommends exclusive breastfeeding during the first six months of life for optimal growth, development and health. Breastfeeding should continue up to two years or more and nutritionally adequate, safe, and appropriately-fed complementary foods should be introduced at the age of six months to meet the evolving needs of the growing infant. Little evidence exists on breastfeeding and infant feeding practices in urban slums in sub-Saharan Africa. Our aim was to assess breastfeeding and infant feeding practices in Nairobi slums with reference to WHO recommendations. Data from a longitudinal study conducted in two Nairobi slums are used. The study used information on the first year of life of 4299 children born between September 2006 and January 2010. All women who gave birth during this period were interviewed on breastfeeding and complementary feeding practices at recruitment and this information was updated twice, at four-monthly intervals. Cox proportional hazard analysis was used to determine factors associated with cessation of breastfeeding in infancy and early introduction of complementary foods. There was universal breastfeeding with almost all children (99%) having ever been breastfed. However, more than a third (37%) were not breastfed in the first hour following delivery, and 40% were given something to drink other than the mothers' breast milk within 3 days after delivery. About 85% of infants were still breastfeeding by the end of the 11th month. Exclusive breastfeeding for the first six months was rare as only about 2% of infants were exclusively breastfed for six months. Factors associated with sub-optimal infant breastfeeding and feeding practices in these settings include child's sex; perceived size at birth; mother's marital status, ethnicity; education level; family planning (pregnancy desirability); health seeking behaviour (place of delivery) and; neighbourhood (slum of residence). The study indicates poor adherence to WHO recommendations for breastfeeding and infant feeding practices. Interventions and further research should pay attention to factors such as cultural practices, access to and utilization of health care facilities, child feeding education, and family planning.

Assessing sex-related chick provisioning in greater flamingo Phoenicopterus roseus parents using capture-recapture models.

PubMed

Rendón, Miguel A; Garrido, Araceli; Rendón-Martos, Manuel; Ramírez, José M; Amat, Juan A

2014-03-01

In sexually dimorphic species, the parental effort of the smaller sex may be reduced due to competitive exclusion in the feeding areas by the larger sex or physiological constraints. However, to determine gender effects on provisioning patterns, other intrinsic and extrinsic factors affecting parental effort should be accounted for. Greater flamingos (Phoenicopterus roseus) exhibit sexual size dimorphism. In Fuente de Piedra colony, the lake dries out almost completely during the breeding season and both parents commute between breeding and foraging sites >130 km away during the chick-rearing period. Applying multistate capture-recapture models to daily observations of marked parents, we determined the effects of sex, and their interactions with other intrinsic and extrinsic factors, on the probability of chick desertion and sojourn in the colony and feeding areas. Moreover, using stable isotopes in the secretions that parents produce to feed their chicks, we evaluated sex-specific use of wetlands. The probability of chick attendance (complementary to chick desertion) was >0.98. Chick desertion was independent of parental sex, but decreased with parental age. Females stayed in the feeding areas for shorter periods [mean: 7.5 (95% CI: 6.0-9.4) days] than males [9.2 (7.3-11.8) days]. Isotopic signatures of secretions did not show sex differences in δ(13)C, but males' secretions were enriched in δ(15)N, suggesting they fed on prey of higher trophic levels than females. Both parents spent approximately 1 day in the colony, but females prolonged their mean stay when the lake dried out. Females also allocated more time to foraging in the flooded areas remaining in the colony, likely because they were energetically more stressed than males. The results indicate that sex-specific provisioning behaviour in greater flamingo is related to differential effects of both intrinsic and extrinsic factors. Males seem forage less efficiently than females, whereas females' body condition seems to be lower after feeding the chick. Our methodology may be extended to species that feed on distant food sources and that do not visit their offspring daily, to elucidate patterns of chick-provisioning behaviour. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

Factors associated with the timing of introduction of complementary feeding: the Generation R Study.

PubMed

Tromp, I I M; Briedé, S; Kiefte-de Jong, J C; Renders, C M; Jaddoe, V W V; Franco, O H; Hofman, A; Raat, H; Moll, H A

2013-06-01

Many parents do not follow recommendations for the timing of introduction of complementary feeding. The aim of this study was to identify determinants associated with the timing of introduction of complementary feeding in a multiethnic birth cohort. Subjects were 3561 mothers and infants participating in a prospective cohort study. The timing of introduction of complementary feeding and maternal and infant characteristics were obtained by parent-derived questionnaires. Regression analyses were performed to identify determinants for the timing of introduction of complementary feeding (<3, 3-6 and ≥ 6 months). In total, 62% of infants were introduced to complementary feeding before the age of 6 months. Determinants for very early (<3 months) introduction were being a single parent and infant day care attendance. Determinants for early (3-6 months) introduction were young maternal age, multiple parities, no infant family history of asthma, atopy and no infant history of allergy to cow's milk. Determinants for both very early and early introduction were low educational level and not fully breastfeeding for 4 months. Maternal educational level was only significantly associated with the timing of introduction in mothers of Western origin. This study confirmed determinants for the timing of introduction of complementary feeding that have been identified by previous studies, which may be appropriate targets for education and guidance. Moreover, mothers whose infants attend day care and have a family history of asthma, atopy or allergy to cow's milk may need guidance to follow infant feeding recommendations.

Groups Rights Struggles Are Mutually Beneficial

ERIC Educational Resources Information Center

Buggs, John A.

1975-01-01

A report on the extent and impact of sex discrimination in America which argues that there is as much legitimacy in the fight for equal rights for women as there is for minorities and that the needs of minorities and women in the field of civil rights are complementary rather than conflicting. (EH)

[Sex and gender: Two different scientific domains to be clarified].

PubMed

Fernández, Juan

2010-05-01

Nowadays, the word sex and its related terms (sexual differences, sexual roles and stereotypes), so common not long ago, seems to have been replaced by gender and its related terms (gender differences, gender roles and stereotypes). We can sometimes find both sex and gender sharing the same space in scientific articles, although referring to different domains. In this paper, I try to explain the need for a model that can integrate both of these complex domains of sex and gender, leading to two independent, although complementary, disciplines: Sexology and Genderology. In both cases, I start from a functional standpoint, which will give meaning to both disciplines' specificities, as it is meant to link contributions from different fields of knowledge. This approach can have consequences for research, education, the experience of women, men, and ambiguous individuals, and therapy.

Masturbation and Partnered Sex: Substitutes or Complements?

PubMed

Regnerus, Mark; Price, Joseph; Gordon, David

2017-10-01

Drawing upon a large, recent probability sample of American adults ages 18-60 (7648 men and 8090 women), we explored the association between sexual frequency and masturbation, evaluating the evidence for whether masturbation compensates for unavailable sex, complements (or augments) existing paired sexual activity, or bears little association with it. We found evidence supporting a compensatory relationship between masturbation and sexual frequency for men, and a complementary one among women, but each association was both modest and contingent on how content participants were with their self-reported frequency of sex. Among men and women, both partnered status and their sexual contentment were more obvious predictors of masturbation than was recent frequency of sex. We conclude that both hypotheses as commonly evaluated suffer from failing to account for the pivotal role of subjective sexual contentment in predicting masturbation.

Nucleotide variability at its limit? Insights into the number and evolutionary dynamics of the sex-determining specificities of the honey bee Apis mellifera.

PubMed

Lechner, Sarah; Ferretti, Luca; Schöning, Caspar; Kinuthia, Wanja; Willemsen, David; Hasselmann, Martin

2014-02-01

Deciphering the evolutionary processes driving nucleotide variation in multiallelic genes is limited by the number of genetic systems in which such genes occur. The complementary sex determiner (csd) gene in the honey bee Apis mellifera is an informative example for studying allelic diversity and the underlying evolutionary forces in a well-described model of balancing selection. Acting as the primary signal of sex determination, diploid individuals heterozygous for csd develop into females, whereas csd homozygotes are diploid males that have zero fitness. Examining 77 of the functional heterozygous csd allele pairs, we established a combinatorical criteria that provide insights into the minimum number of amino acid differences among those pairs. Given a data set of 244 csd sequences, we show that the total number of csd alleles found in A. mellifera ranges from 53 (locally) to 87 (worldwide), which is much higher than was previously reported (20). Using a coupon-collector model, we extrapolate the presence of in total 116-145 csd alleles worldwide. The hypervariable region (HVR) is of particular importance in determining csd allele specificity, and we provide for this region evidence of high evolutionary rate for length differences exceeding those of microsatellites. The proportion of amino acids driven by positive selection and the rate of nonsynonymous substitutions in the HVR-flanking regions reach values close to 1 but differ with respect to the HVR length. Using a model of csd coalescence, we identified the high originating rate of csd specificities as a major evolutionary force, leading to an origin of a novel csd allele every 400,000 years. The csd polymorphism frequencies in natural populations indicate an excess of new mutations, whereas signs of ancestral transspecies polymorphism can still be detected. This study provides a comprehensive view of the enormous diversity and the evolutionary forces shaping a multiallelic gene.

Nucleotide Variability at Its Limit? Insights into the Number and Evolutionary Dynamics of the Sex-Determining Specificities of the Honey Bee Apis mellifera

PubMed Central

Lechner, Sarah; Ferretti, Luca; Schöning, Caspar; Kinuthia, Wanja; Willemsen, David; Hasselmann, Martin

2014-01-01

Deciphering the evolutionary processes driving nucleotide variation in multiallelic genes is limited by the number of genetic systems in which such genes occur. The complementary sex determiner (csd) gene in the honey bee Apis mellifera is an informative example for studying allelic diversity and the underlying evolutionary forces in a well-described model of balancing selection. Acting as the primary signal of sex determination, diploid individuals heterozygous for csd develop into females, whereas csd homozygotes are diploid males that have zero fitness. Examining 77 of the functional heterozygous csd allele pairs, we established a combinatorical criteria that provide insights into the minimum number of amino acid differences among those pairs. Given a data set of 244 csd sequences, we show that the total number of csd alleles found in A. mellifera ranges from 53 (locally) to 87 (worldwide), which is much higher than was previously reported (20). Using a coupon-collector model, we extrapolate the presence of in total 116–145 csd alleles worldwide. The hypervariable region (HVR) is of particular importance in determining csd allele specificity, and we provide for this region evidence of high evolutionary rate for length differences exceeding those of microsatellites. The proportion of amino acids driven by positive selection and the rate of nonsynonymous substitutions in the HVR-flanking regions reach values close to 1 but differ with respect to the HVR length. Using a model of csd coalescence, we identified the high originating rate of csd specificities as a major evolutionary force, leading to an origin of a novel csd allele every 400,000 years. The csd polymorphism frequencies in natural populations indicate an excess of new mutations, whereas signs of ancestral transspecies polymorphism can still be detected. This study provides a comprehensive view of the enormous diversity and the evolutionary forces shaping a multiallelic gene. PMID:24170493

Effect on embryos of injection of phosphorothioate-modified oligonucleotides into pregnant mice.

PubMed

Gaudette, M F; Hampikian, G; Metelev, V; Agrawal, S; Crain, W R

1993-01-01

Phosphorothioate-modified oligonucleotides were injected into pregnant female mice to assess the effect on developing embryos. Injections were carried out during two different time periods, one when embryos were in preimplantation stages of development (about 3.5 days of development) and the other after implantation, when both a fetus and placenta are present (from days 9.5 to 11.5 of development). Three different phosphorothioate-modified oligonucleotides were injected. One, which had a sequence not present in the mouse genome, was used to ask whether nonspecific toxic or teratogenic effects on embryos result from treatment of the mother. A second was complementary to the mRNA of the testis-determining factor gene Sry and was used to ask whether a specific developmental pathway (i.e., sex determination) could be disrupted in embryos in vivo. The third was the complement of the anti-Sry sequence. None of these oligonucleotides reduced the frequency of successful pregnancy after mating or the average litter size from that observed in controls animals. Furthermore, examination of 291 pups or fetuses from all oligonucleotide-injected pregnant females revealed no developmental defects regardless of which sequence was used. It is concluded that injection of phosphorothioate-modified oligonucleotides into pregnant females according to the protocols described here is not toxic or teratogenic to embryos in a nonspecific way. Also, anti-Sry oligonucleotides did not influence sex determination in embryos, although there are several possible explanations for this.

Household food security and infant feeding practices in rural Bangladesh.

PubMed

Owais, Aatekah; Kleinbaum, David G; Suchdev, Parminder S; Faruque, Asg; Das, Sumon K; Schwartz, Benjamin; Stein, Aryeh D

2016-07-01

To determine the association between household food security and infant complementary feeding practices in rural Bangladesh. Prospective, cohort study using structured home interviews during pregnancy and 3 and 9 months after delivery. We used two indicators of household food security at 3-months' follow-up: maternal Food Composition Score (FCS), calculated via the World Food Programme method, and an HHFS index created from an eleven-item food security questionnaire. Infant feeding practices were characterized using WHO definitions. Two rural sub-districts of Kishoreganj, Bangladesh. Mother-child dyads (n 2073) who completed the 9-months' follow-up. Complementary feeding was initiated at age ≤4 months for 7 %, at 5-6 months for 49 % and at ≥7 months for 44 % of infants. Based on 24 h dietary recall, 98 % of infants were still breast-feeding at age 9 months, and 16 % received ≥4 food groups and ≥4 meals (minimally acceptable diet) in addition to breast milk. Mothers' diet was more diverse than infants'. The odds of receiving a minimally acceptable diet for infants living in most food-secure households were three times those for infants living in least food-secure households (adjusted OR=3·0; 95 % CI 2·1, 4·3). Socio-economic status, maternal age, literacy, parity and infant sex were not associated with infant diet. HHFS and maternal FCS were significant predictors of subsequent infant feeding practices. Nevertheless, even the more food-secure households had poor infant diet. Interventions aimed at improving infant nutritional status need to focus on both complementary food provision and education.

Sexual economics: sex as female resource for social exchange in heterosexual interactions.

PubMed

Baumeister, Roy F; Vohs, Kathleen D

2004-01-01

A heterosexual community can be analyzed as a marketplace in which men seek to acquire sex from women by offering other resources in exchange. Societies will therefore define gender roles as if women are sellers and men buyers of sex. Societies will endow female sexuality, but not male sexuality, with value (as in virginity, fidelity, chastity). The sexual activities of different couples are loosely interrelated by a marketplace, instead of being fully separate or private, and each couple's decisions may be influenced by market conditions. Economic principles suggest that the price of sex will depend on supply and demand, competition among sellers, variations in product, collusion among sellers, and other factors. Research findings show gender asymmetries (reflecting the complementary economic roles) in prostitution, courtship, infidelity and divorce, female competition, the sexual revolution and changing norms, unequal status between partners, cultural suppression of female sexuality, abusive relationships, rape, and sexual attitudes.

Experimental Comparison Between Mahoney and Complementary Sensor Fusion Algorithm for Attitude Determination by Raw Sensor Data of Xsens Imu on Buoy

NASA Astrophysics Data System (ADS)

Jouybari, A.; Ardalan, A. A.; Rezvani, M.-H.

2017-09-01

The accurate measurement of platform orientation plays a critical role in a range of applications including marine, aerospace, robotics, navigation, human motion analysis, and machine interaction. We used Mahoney filter, Complementary filter and Xsens Kalman filter for achieving Euler angle of a dynamic platform by integration of gyroscope, accelerometer, and magnetometer measurements. The field test has been performed in Kish Island using an IMU sensor (Xsens MTi-G-700) that installed onboard a buoy so as to provide raw data of gyroscopes, accelerometers, magnetometer measurements about 25 minutes. These raw data were used to calculate the Euler angles by Mahoney filter and Complementary filter, while the Euler angles collected by XSense IMU sensor become the reference of the Euler angle estimations. We then compared Euler angles which calculated by Mahoney Filter and Complementary Filter with reference to the Euler angles recorded by the XSense IMU sensor. The standard deviations of the differences between the Mahoney Filter, Complementary Filter Euler angles and XSense IMU sensor Euler angles were about 0.5644, 0.3872, 0.4990 degrees and 0.6349, 0.2621, 2.3778 degrees for roll, pitch, and heading, respectively, so the numerical result assert that Mahoney filter is precise for roll and heading angles determination and Complementary filter is precise only for pitch determination, it should be noted that heading angle determination by Complementary filter has more error than Mahoney filter.

Plasma esterases in the tegu lizard Tupinambis merianae (Reptilia, Teiidae): impact of developmental stage, sex, and organophosphorus in vitro exposure.

PubMed

Basso, Agustín; Attademo, Andrés M; Lajmanovich, Rafael C; Peltzer, Paola M; Junges, Celina; Cabagna, Mariana C; Fiorenza, Gabriela S; Sanchez-Hernandez, Juan Carlos

2012-01-01

In this study, we determined normal serum butyrylcholinesterase (BChE) and carboxylesterase (CbE) activities in Tupinambis merianae in order to obtain reference values for organophosphorus pesticide monitoring. Forty-two T. merianae individuals were grouped by sex and size to identify potential differences in their enzyme levels to allow for proper representation of normal values for females, males, juveniles, and hatchlings. Mean CbE was determined using two model substrates: alpha-naphtylacetate (α-NA) and p-nitrophenyl valerate (4-NPV). BChE and CbE sensitivity to malaoxon (Mx) was also evaluated as well as the possibility of BChE reactivation with pyridine-2-aldoxime methochloride (2-PAM). Mean adult females' BChE was significantly higher than adult males, juveniles, and hatchlings. No significant differences were found between groups regarding CbE. CbE (4-NPV) activity showed slightly negative correlation with lizard snout-vent length, while BChE and CbE (α-NA) showed no correlation with body size. Apparent IC(50) values for BChE and CbE (α-NA) suggested different sensitivities among groups. CbE (4-NPV) could not be inhibited. All Mx-inhibited groups treated with 2-PAM in a final concentration of 2.8 mM showed clear signs of reactivation. In conclusion, the results demonstrate that (1) plasma esterase activity did not vary with age and sex, except for BChE activity, and (2) because biological and environmental variables could be confounding factors in the response of plasma cholinesterases, complementary biomarkers like CbE inhibition and oxime-induced reactivation of esterases are strongly recommended.

Genetic incompatibility drives mate choice in a parasitic wasp.

PubMed

Thiel, Andra; Weeda, Anne C; de Boer, Jetske G; Hoffmeister, Thomas S

2013-07-30

Allelic incompatibility between individuals of the same species should select for mate choice based on the genetic make-up of both partners at loci that influence offspring fitness. As a consequence, mate choice may be an important driver of allelic diversity. A complementary sex determination (CSD) system is responsible for intraspecific allelic incompatibility in many species of ants, bees, and wasps. CSD may thus favour disassortative mating and in this, resembles the MHC of the vertebrate immune system, or the self-incompatibility (SI) system of higher plants. Here we show that in the monogamous parasitic wasp Bracon brevicornis (Wesmael), females are able to reject partners with incompatible alleles. Forcing females to accept initially rejected partners resulted in sex ratio distortion and partial infertility of offspring. CSD-disassortative mating occurred independent of kin recognition and inbreeding avoidance in our experiment. The fitness consequences of mate choice are directly observable, not influenced by environmental effects, and more severe than in comparable systems (SI or MHC), on individuals as well as at the population level. Our results thus demonstrate the strong potential of female mate choice for maintaining high offspring fitness in this species.

A rapid procedure for measurement of the free testosterone fraction in human plasma using the centria radioimmunoassay centrifugal analyzer.

PubMed

Schwarz, S; Boyd, J

1981-01-01

Following the incubation of plasma with a tracer amount of tritiated testosterone, the reaction mixture is separated into a sex hormone-binding globulin bound and an unbound fraction of radioligand using DEAE-cellulose columns placed in the incubator-separator module of the Centria radioimmunoassay centrifugal analyzer. Neural Tris-buffer elutes unbound steroid from the matrix, while acidic Tris-buffer can remove the protein-bound fraction in a subsequent step. Complementary and thus qualitatively equal results are obtained when counting either eluate. Comparison of this technique with an ammonium sulfate precipitation method showed high correlation. Free testosterone indices as determined by the Centria modification in a number of prepuberal children, normal men and women, as well as pregnant and hirsute women similar to those previously reported.

Complementary and alternative medicine usage and its determinant factors among Iranian infertile couples.

PubMed

Dehghan, Mahlagha; Mokhtarabadi, Sima; Heidari, Fatemeh Ghaedi

2018-04-04

Background The aim of this study was to determine the status of utilizing some complementary and alternative medicine techniques in infertile couples. Methods This was a cross-sectional study conducted on 250 infertile couples referred to a hospital in Kerman using convenience sampling. A researcher-made questionnaire was used to study the prevalence and user satisfaction of complementary and alternative medicines. Results Results indicated that 49.6% of the infertile couples used at least one of the complementary and alternative medicines during the past year. Most individuals used spiritual techniques (71.8% used praying and 70.2% used Nazr) and medicinal plants (54.8%). Safety is the most important factor affecting the satisfaction of infertile couples with complementary treatments (couples think that such treatments are safe (54.8%)). Discussion Concerning high prevalence of complementary and alternative treatments in infertile couples, incorporating such treatments into the healthcare education and promoting the awareness of infertile individuals seem crucial.

Genomics of sex determination.

PubMed

Zhang, Jisen; Boualem, Adnane; Bendahmane, Abdelhafid; Ming, Ray

2014-04-01

Sex determination is a major switch in the evolutionary history of angiosperm, resulting 11% monoecious and dioecious species. The genomic sequences of papaya sex chromosomes unveiled the molecular basis of recombination suppression in the sex determination region, and candidate genes for sex determination. Identification and analyses of sex determination genes in cucurbits and maize demonstrated conservation of sex determination mechanism in one lineage and divergence between the two systems. Epigenetic control and hormonal influence of sex determination were elucidated in both plants and animals. Intensive investigation of potential sex determination genes in model species will improve our understanding of sex determination gene network. Such network will in turn accelerate the identification of sex determination genes in dioecious species with sex chromosomes, which are burdensome due to no recombination in sex determining regions. The sex determination genes in dioecious species are crucial for understanding the origin of dioecy and sex chromosomes, particularly in their early stage of evolution. Copyright © 2014 Elsevier Ltd. All rights reserved.

Usefulness of telomere length in DNA from human teeth for age estimation.

PubMed

Márquez-Ruiz, Ana Belén; González-Herrera, Lucas; Valenzuela, Aurora

2018-03-01

Age estimation is widely used to identify individuals in forensic medicine. However, the accuracy of the most commonly used procedures is markedly reduced in adulthood, and these methods cannot be applied in practice when morphological information is limited. Molecular methods for age estimation have been extensively developed in the last few years. The fact that telomeres shorten at each round of cell division has led to the hypothesis that telomere length can be used as a tool to predict age. The present study thus aimed to assess the correlation between telomere length measured in dental DNA and age, and the effect of sex and tooth type on telomere length; a further aim was to propose a statistical regression model to estimate the biological age based on telomere length. DNA was extracted from 91 tooth samples belonging to 77 individuals of both sexes and 15 to 85 years old and was used to determine telomere length by quantitative real-time PCR. Our results suggested that telomere length was not affected by sex and was greater in molar teeth. We found a significant correlation between age and telomere length measured in DNA from teeth. However, the equation proposed to predict age was not accurate enough for forensic age estimation on its own. Age estimation based on telomere length in DNA from tooth samples may be useful as a complementary method which provides an approximate estimate of age, especially when human skeletal remains are the only forensic sample available.

Sex reversal triggers the rapid transition from genetic to temperature-dependent sex.

PubMed

Holleley, Clare E; O'Meally, Denis; Sarre, Stephen D; Marshall Graves, Jennifer A; Ezaz, Tariq; Matsubara, Kazumi; Azad, Bhumika; Zhang, Xiuwen; Georges, Arthur

2015-07-02

Sex determination in animals is amazingly plastic. Vertebrates display contrasting strategies ranging from complete genetic control of sex (genotypic sex determination) to environmentally determined sex (for example, temperature-dependent sex determination). Phylogenetic analyses suggest frequent evolutionary transitions between genotypic and temperature-dependent sex determination in environmentally sensitive lineages, including reptiles. These transitions are thought to involve a genotypic system becoming sensitive to temperature, with sex determined by gene-environment interactions. Most mechanistic models of transitions invoke a role for sex reversal. Sex reversal has not yet been demonstrated in nature for any amniote, although it occurs in fish and rarely in amphibians. Here we make the first report of reptile sex reversal in the wild, in the Australian bearded dragon (Pogona vitticeps), and use sex-reversed animals to experimentally induce a rapid transition from genotypic to temperature-dependent sex determination. Controlled mating of normal males to sex-reversed females produces viable and fertile offspring whose phenotypic sex is determined solely by temperature (temperature-dependent sex determination). The W sex chromosome is eliminated from this lineage in the first generation. The instantaneous creation of a lineage of ZZ temperature-sensitive animals reveals a novel, climate-induced pathway for the rapid transition between genetic and temperature-dependent sex determination, and adds to concern about adaptation to rapid global climate change.

Diploid male dynamics under different numbers of sexual alleles and male dispersal abilities.

PubMed

Faria, Luiz R R; Soares, Elaine Della Giustina; Carmo, Eduardo do; Oliveira, Paulo Murilo Castro de

2016-09-01

Insects in the order Hymenoptera (bees, wasps and ants) present an haplodiploid system of sexual determination in which fertilized eggs become females and unfertilized eggs males. Under single locus complementary sex-determination (sl-CSD) system, the sex of a specimen depends on the alleles at a single locus: when diploid, an individual will be a female if heterozygous and male if homozygous. Significant diploid male (DM) production may drive a population to an extinction scenario called "diploid male vortex". We aimed at studying the dynamics of populations of a sl-CSD organism under several combinations of two parameters: male flight abilities and number of sexual alleles. In these simulations, we evaluated the frequency of DM and a genetic diversity measure over 10,000 generations. The number of sexual alleles varied from 10 to 100 and, at each generation, a male offspring might fly to another random site within a varying radius R. Two main results emerge from our simulations: (i) the number of DM depends more on male flight radius than on the number of alleles; (ii) in large geographic regions, the effect of males flight radius on the allelic diversity turns out much less pronounced than in small regions. In other words, small regions where inbreeding normally appears recover genetic diversity due to large flight radii. These results may be particularly relevant when considering the population dynamics of species with increasingly limited dispersal ability (e.g., forest-dependent species of euglossine bees in fragmented landscapes).

Molecular players involved in temperature-dependent sex determination and sex differentiation in Teleost fish

PubMed Central

2014-01-01

The molecular mechanisms that underlie sex determination and differentiation are conserved and diversified. In fish species, temperature-dependent sex determination and differentiation seem to be ubiquitous and molecular players involved in these mechanisms may be conserved. Although how the ambient temperature transduces signals to the undifferentiated gonads remains to be elucidated, the genes downstream in the sex differentiation pathway are shared between sex-determining mechanisms. In this paper, we review recent advances on the molecular players that participate in the sex determination and differentiation in fish species, by putting emphasis on temperature-dependent sex determination and differentiation, which include temperature-dependent sex determination and genetic sex determination plus temperature effects. Application of temperature-dependent sex differentiation in farmed fish and the consequences of temperature-induced sex reversal are discussed. PMID:24735220

The interactive association of dietary diversity scores and breast-feeding status with weight and length in Filipino infants aged 6-24 months.

PubMed

Wright, Melecia J; Bentley, Margaret E; Mendez, Michelle A; Adair, Linda S

2015-07-01

To assess how breast-feeding and dietary diversity relate to infant length-for-age Z-score (LAZ) and weight-for-age Z-score (WAZ). Breast-feeding, dietary and anthropometric data from the Cebu Longitudinal Health and Nutrition Survey were analysed using sex-stratified fixed-effects longitudinal regression models. A dietary diversity score (DDS) based on seven food groups was classified as low (<4) or high (≥ 4). The complementary feeding patterns were: (i) non-breast-fed with low DDS (referent); (ii) breast-fed with low DDS; (iii) non-breast-fed with high DDS; and (iv) breast-fed with high DDS (optimal). Interactions between age, energy intake and complementary feeding patterns were included. Philippines. Infants (n 2822) measured bimonthly from 6 to 24 months. Breast-feeding (regardless of DDS) was significantly associated with higher LAZ (until 24 months) and WAZ (until 20 months). For example, at 6 months, breast-fed boys with low DDS were 0.246 (95% CI 0.191, 0.302) sd longer and 0.523 (95% CI 0.451, 0.594) sd heavier than the referent group. There was no significant difference in size between breast-fed infants with high v. low DDS. Similarly, high DDS conferred no advantage in LAZ or WAZ among non-breast-fed infants. There were modest correlations between the 7-point DDS and nutrient intakes but these correlations were substantially attenuated after energy adjustment. We elucidated several interactions between sex, age, energy intake and complementary feeding patterns. These results demonstrate the importance of prolonged breast-feeding up to 24 months. The DDS provided qualitative information on infant diets but did not confer a significant advantage in LAZ or WAZ.

Determining the attitudes and use of complementary, alternative, and integrative medicine among undergraduates.

PubMed

Liu, Michael A; Huynh, Ngoc-Tram; Broukhim, Michael; Cheung, Douglas H; Schuster, Tonya L; Najm, Wadie

2014-09-01

To (1) determine the attitudes, perceptions, and use of complementary, alternative, and integrative medicine among undergraduate students; (2) assess whether these students would benefit from more academic exposure to complementary and alternative medicine (CAM) and promotion of integrative medicine (IM); and (3) gauge the need and desire of undergraduates, particularly pre-health learners, to take courses about CAM/IM. This cross-sectional electronic survey study was conducted on the campus of the University of California (UC) Irvine. Selection criteria included being at least 18 years of age and a current undergraduate at UC Irvine. All survey responses were collected between November 20, 2010, and June 1, 2011. The data were analyzed by using Stata software, version 11-SE (Stata Corp., College Station, TX). Completed surveys were received from 2839 participants (mean age of respondents, 20.2 years). Thirty-five percent had used CAM within the past 12 months, and 92.8% believed CAM to be at least somewhat effective; however, only 31% had prior education on CAM. After adjustment for variables, familiarity and belief in effectiveness were both highly linked to the use of CAM, with ascending odds ratios (ORs; 95% confidence interval [CI]) of 3.9 (3.1-4.9), 8.1 (5.7-11.5), 13.4 (6.0-30.2), 2.1 (1.3-3.4), 4.9 (3.0-7.8), and 12.7 (6.9-23.4) among increasing categories (all p<0.01). Sex (OR, 1.26 [95% CI, 1.01-1.56]; p<0.05), Asian ethnicity (1.46 [1.14-1.88]; p<0.01), and prior education (1.26 [1.01-1.57]; p<0.05) were also significantly correlated to the use of CAM after adjustment. Most respondents indicated that they were likely to take a CAM college course if it fulfilled a graduation requirement (63.6%) or was offered within their major (56.4%). Overall, this large-scale study supports the ideas that education plays a pivotal factor in the decision to use CAM and that there is a large demand for additional CAM knowledge among college students.

Vasopressin and oxytocin receptor systems in the brain: sex differences and sex-specific regulation of social behavior

PubMed Central

Dumais, Kelly M.; Veenema, Alexa H.

2015-01-01

The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species- specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. PMID:25951955

Vasopressin and oxytocin receptor systems in the brain: Sex differences and sex-specific regulation of social behavior.

PubMed

Dumais, Kelly M; Veenema, Alexa H

2016-01-01

The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species-specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. Copyright © 2015 Elsevier Inc. All rights reserved.

Prevalence, Types and Determinants of Complementary and Alternative Medications among Health Clinic Clients

ERIC Educational Resources Information Center

Almousa, H.; Rabie, Faten M.; Alsamghan, Awad S.; Alsaluli, Mobarak; Albqami, Sultan; Almusa, Mona; Al-shahrani, Areej

2015-01-01

Complementary and Alternative Medicine (CAM) covers a wide range of over 100 healing approaches, philosophies and therapeutic modalities that are not provided by conventional medicine. Objectives: The study was aimed at identifying the prevalence, types and determinants of CAM use, sources of information about CAM that patients usually depend upon…

Variability in sex-determining mechanisms influences genome complexity in reptilia.

PubMed

Janes, D E; Organ, C L; Edwards, S V

2009-01-01

In this review, we describe the history of amniote sex determination as a classic example of Darwinian evolution. We suggest that evolutionary changes in sex determination provide a foundation for understanding important aspects of chromosome and genome organization that otherwise appear haphazard in their origins and contents. Species with genotypic sex determination often possess heteromorphic sex chromosomes, whereas species with environmental sex determination lack them. Through a series of mutations followed by selection at key genes, sex-determining mechanisms have turned over many times throughout the amniote lineage. As a consequence, amniote genomes have undergone gains or losses of sex chromosomes. We review the genomic and ecological contexts in which either temperature-dependent or genotypic sex determination has evolved. Once genotypic sex determination emerges in a lineage, viviparity and heteromorphic sex chromosomes become more likely to evolve. For example, in extinct marine reptiles, genotypic sex determination apparently led to viviparity, which in turn facilitated their pelagic radiation. Sex chromosomes comprise genome regions that differ from autosomes in recombination rate, mutation rate, levels of polymorphism, and the presence of sex-determining and sexually antagonistic genes. In short, many aspects of amniote genome complexity, life history, and adaptive radiation appear contingent on evolutionary changes in sex-determining mechanisms. Copyright 2010 S. Karger AG, Basel.

Variability in Sex-Determining Mechanisms Influences Genome Complexity in Reptilia

PubMed Central

Janes, D.E.; Organ, C.L.; Edwards, S.V.

2010-01-01

In this review, we describe the history of amniote sex determination as a classic example of Darwinian evolution. We suggest that evolutionary changes in sex determination provide a foundation for understanding important aspects of chromosome and genome organization that otherwise appear haphazard in their origins and contents. Species with genotypic sex determination often possess heteromorphic sex chromosomes, whereas species with environmental sex determination lack them. Through a series of mutations followed by selection at key genes, sex-determining mechanisms have turned over many times throughout the amniote lineage. As a consequence, amniote genomes have undergone gains or losses of sex chromosomes. We review the genomic and ecological contexts in which either temperature-dependent or genotypic sex determination has evolved. Once genotypic sex determination emerges in a lineage, viviparity and heteromorphic sex chromosomes become more likely to evolve. For example, in extinct marine reptiles, genotypic sex determination apparently led to viviparity, which in turn facilitated their pelagic radiation. Sex chromosomes comprise genome regions that differ from autosomes in recombination rate, mutation rate, levels of polymorphism, and the presence of sex-determining and sexually antagonistic genes. In short, many aspects of amniote genome complexity, life history, and adaptive radiation appear contingent on evolutionary changes in sex-determining mechanisms. PMID:20203474

Individual differences in melancholy gender among women: does ambivalence matter?

PubMed

Jay, Meg

2007-01-01

This research offers an empirical investigation inspired by Butler's theory of melancholy gender (1995) and a revision of this theory (Jay 2007a). Psychoanalytic feminist theory is drawn on to suggest that melancholy and gender are more likely to be associated in female development than in male development, and Freud's theory of melancholy (1917) is taken to suggest that ambivalence predicts individual differences in melancholy gender among women. In a longitudinal study of women's adult development, an examination of femininity, depressive symptoms, and ambivalence in attachment was conducted in order to evaluate these claims. Findings show that depressive symptoms and femininity are significantly correlated within the sample, but that individual differences in melancholy gender exist. To understand these differences, an analysis was conducted to determine whether ambivalence in attachment accounts for the relation between depressive symptoms and femininity; complementary analyses examined whether low ambivalence in attachment attenuates, or lessens, the relation between femininity and depressive symptoms. Results from these analyses support the notion that it is not the loss and internalization of the same-sex object choice per se that results in melancholy gender in women, as Butler argues; rather, it is the internalization of a lost, ambivalent same-sex attachment that forges the link between melancholy and gender. Narrative material is presented to personify melancholy and unmelancholy gender.

Occupational epidemiology and work related inequalities in health: a gender perspective for two complementary approaches to work and health research

PubMed Central

Artazcoz, Lucía; Borrell, Carme; Cortès, Imma; Escribà‐Agüir, Vicenta; Cascant, Lorena

2007-01-01

Objectives To provide a framework for epidemiological research on work and health that combines classic occupational epidemiology and the consideration of work in a structural perspective focused on gender inequalities in health. Methods Gaps and limitations in classic occupational epidemiology, when considered from a gender perspective, are described. Limitations in research on work related gender inequalities in health are identified. Finally, some recommendations for future research are proposed. Results Classic occupational epidemiology has paid less attention to women's problems than men's. Research into work related gender inequalities in health has rarely considered either social class or the impact of family demands on men's health. In addition, it has rarely taken into account the potential interactions between gender, social class, employment status and family roles and the differences in social determinants of health according to the health indicator analysed. Conclusions Occupational epidemiology should consider the role of sex and gender in examining exposures and associated health problems. Variables should be used that capture the specific work environments and health conditions of both sexes. The analysis of work and health from a gender perspective should take into account the complex interactions between gender, family roles, employment status and social class. PMID:18000116

Attitudes towards and personal use of complementary and alternative medicine amongst clinicians working in audiovestibular disciplines.

PubMed

Crundwell, G; Baguley, D M

2016-08-01

Literature indicates that complementary and alternative medicine is used by patients with auditory and vestibular symptoms. This study sought to determine the prevalence of complementary and alternative medicine uptake, and examine attitudes towards complementary and alternative medicine in clinicians working with audiovestibular disorder patients. The Holistic Complementary and Alternative Medicine Questionnaire and a devised questionnaire about recent and lifetime use of complementary and alternative medicine were used. Fifty-four individuals, including audiologists, ENT surgeons, nurses and rehabilitationists, completed the questionnaires (67 per cent response rate). Lifetime prevalence of complementary and alternative medicine uptake was 44 per cent, and 12-month prevalence was 22 per cent. Uptake was more common in females, but there was no significant difference in use when comparing age, seniority or profession. Attitudes towards complementary and alternative medicine were mildly adverse, but sizeable standard deviation indicates wide-ranging attitudes. Clinicians working with patients with audiovestibular disorders have a range of attitudes towards complementary and alternative medicine. Personal uptake of complementary and alternative medicine was lower than that of the general UK population, but remains sizeable.

Determining Complementary Properties with Quantum Clones.

PubMed

Thekkadath, G S; Saaltink, R Y; Giner, L; Lundeen, J S

2017-08-04

In a classical world, simultaneous measurements of complementary properties (e.g., position and momentum) give a system's state. In quantum mechanics, measurement-induced disturbance is largest for complementary properties and, hence, limits the precision with which such properties can be determined simultaneously. It is tempting to try to sidestep this disturbance by copying the system and measuring each complementary property on a separate copy. However, perfect copying is physically impossible in quantum mechanics. Here, we investigate using the closest quantum analog to this copying strategy, optimal cloning. The coherent portion of the generated clones' state corresponds to "twins" of the input system. Like perfect copies, both twins faithfully reproduce the properties of the input system. Unlike perfect copies, the twins are entangled. As such, a measurement on both twins is equivalent to a simultaneous measurement on the input system. For complementary observables, this joint measurement gives the system's state, just as in the classical case. We demonstrate this experimentally using polarized single photons.

Determining Complementary Properties with Quantum Clones

NASA Astrophysics Data System (ADS)

Thekkadath, G. S.; Saaltink, R. Y.; Giner, L.; Lundeen, J. S.

2017-08-01

In a classical world, simultaneous measurements of complementary properties (e.g., position and momentum) give a system's state. In quantum mechanics, measurement-induced disturbance is largest for complementary properties and, hence, limits the precision with which such properties can be determined simultaneously. It is tempting to try to sidestep this disturbance by copying the system and measuring each complementary property on a separate copy. However, perfect copying is physically impossible in quantum mechanics. Here, we investigate using the closest quantum analog to this copying strategy, optimal cloning. The coherent portion of the generated clones' state corresponds to "twins" of the input system. Like perfect copies, both twins faithfully reproduce the properties of the input system. Unlike perfect copies, the twins are entangled. As such, a measurement on both twins is equivalent to a simultaneous measurement on the input system. For complementary observables, this joint measurement gives the system's state, just as in the classical case. We demonstrate this experimentally using polarized single photons.

Values for gender roles and relations among high school and non-high school adolescents in a Maya community in Chiapas, Mexico.

PubMed

Manago, Adriana M

2015-02-01

In the current study, I describe values for gender roles and cross-sex relations among adolescents growing up in a southern Mexican Maya community in which high school was introduced in 1999. A total of 80 adolescent girls and boys, half of whom were attending the new high school, provided their opinions on two ethnographically derived vignettes that depicted changes in gender roles and relations occurring in their community. Systematic coding revealed that adolescents not enrolled in high school tended to prioritise ascribed and complementary gender roles and emphasise the importance of family mediation in cross-sex relations. Adolescents who were enrolled in high school tended to prioritise equivalent and chosen gender roles, and emphasised personal responsibility and personal fulfillment in cross-sex relations. Perceptions of risks and opportunities differed by gender: girls favourably evaluated the expansion of adult female role options, but saw risks in personal negotiations of cross-sex relations; boys emphasised the loss of the female homemaker role, but favourably evaluated new opportunities for intimacy in cross-sex relations. © 2014 International Union of Psychological Science.

Sex determination in papaya.

PubMed

Ming, Ray; Yu, Qingyi; Moore, Paul H

2007-06-01

Sex determination is an intriguing system in trioecious papaya. Over the past seven decades various hypotheses, based on the knowledge and information available at the time, have been proposed to explain the genetics of the papaya's sex determination. These include a single gene with three alleles, a group of closely linked genes, a genic balance of sex chromosome over autosomes, classical XY chromosomes, and regulatory elements of the flower development pathway. Recent advancements in genomic technology make it possible to characterize the genomic region involved in sex determination at the molecular level. High density linkage mapping validated the hypothesis that predicted recombination suppression at the sex determination locus. Physical mapping and sample sequencing of the non-recombination region led to the conclusion that sex determination is controlled by a pair of primitive sex chromosomes with a small male-specific region (MSY) of the Y chromosome. We now postulate that two sex determination genes control the sex determination pathway. One, a feminizing or stamen suppressor gene, causes stamen abortion before or at flower inception while the other, a masculinizing or carpel suppressor gene, causes carpel abortion at a later flower developmental stage. Detailed physical mapping is beginning to reveal structural details about the sex determination region and sequencing is expected to uncover candidate sex determining genes. Cloning of the sex determination genes and understanding the sex determination process could have profound application in papaya production.

Selected endocrine disrupting compounds (vinclozolin, flutamide, ketoconazole and dicofol): effects on survival, occurrence of males, growth, molting and reproduction of Daphnia magna.

PubMed

Haeba, Maher H; Hilscherová, Klára; Mazurová, Edita; Bláha, Ludek

2008-05-01

Pollution-induced endocrine disruption in vertebrates and invertebrates is a worldwide environmental problem, but relatively little is known about effects of endocrine disrupting compounds (EDCs) in planktonic crustaceans (including Daphnia magna). Aims of the present study were to investigate acute 48 h toxicity and sub-chronic (4-6 days) and chronic (21 days) effects of selected EDCs in D. magna. We have investigated both traditional endpoints as well as other parameters such as sex determination, maturation, molting or embryogenesis in order to evaluate the sensitivity and possible use of these endpoints in ecological risk assessment. We have studied effects of four model EDCs (vinclozolin, flutamide, ketoconazole and dicofol) on D. magna using (i) an acute 48 h immobilization assay, (ii) a sub-chronic, 4-6 day assay evaluating development and the sex ratio of neonates, and (iii) a chronic, 21 day assay studying number of neonates, sex of neonates, molting frequency, day of maturation and the growth of maternal organisms. Acute EC50 values in the 48 h immobilization test were as follows (mg/L): dicofol 0.2, ketoconazole 1.5, flutamide 2.7, vinclozolin >3. Short-term, 4-6 day assays with sublethal concentrations showed that the sex ratio in Daphnia was modulated by vinclozolin (decreased number of neonate males at 1 mg/L) and dicofol (increase in males at 0.1 mg/L). Flutamide (up to 1 mg/L) had no effect on the sex of neonates, but inhibited embryonic development at certain stages during chronic assay, resulting in abortions. Ketoconazole had no significant effects on the studied processes up to 1 mg/L. Sex ratio modulations by some chemicals (vinclozolin and dicofol) corresponded to the known action of these compounds in vertebrates (i.e. anti-androgenicity and anti-oestrogenicity, respectively). Our study revealed that some chemicals known to affect steroid-regulated processes in vertebrates can also affect sublethal endpoints (e.g. embryonic sex determination and/or reproduction) in invertebrates such as D. magna. A series of model vertebrate endocrine disrupters affected various sub-chronic and chronic parameters in D. magna including several endpoints that have not been previously studied in detail (such as sex determination in neonates, embryogenesis, molting and maturation). Evaluations of traditional reproduction parameters (obtained from the 21 day chronic assay). as well as the results from a rapid, 4-6 day, sub-chronic assay provide complementary information on non-lethal effects of suspected organic endocrine disrupters. It seems that there are analogies between vertebrates and invertebrates in toxicity mechanisms and in vivo effects of endocrine disruptors. However, general physiological status of organisms may also indirectly affect endpoints that are traditionally considered 'hormone regulated' (especially at higher effective concentrations as observed in this study) and these factors should be carefully considered. Further research of D. magna physiology and comparative studies with various EDCs will help to understand mechanisms of action as well as ecological risks of EDCs in the environment.

Use of complementary and alternative medicine by patients with cancer in northern Turkey: analysis of cost and satisfaction.

PubMed

Aydin Avci, Ilknur; Koç, Zeliha; Sağlam, Zeynep

2012-03-01

The aims of this study were to determine (1) the prevalence of complementary and alternative medicine use among patients with cancer, (2) the method of use of the particular therapy, (3) the reasons for using complementary and alternative medicine therapies, (4) the benefits experienced by the use of complementary and alternative medicine, (5) the source of information about complementary and alternative medicine therapies and, (6) the satisfaction and cost of complementary and alternative medicine. Complementary and alternative medicine consists of diverse medical and healthcare systems, practices and products that are not considered at present to be a part of conventional medicine. The majority of patients who use complementary and alternative medicine use more than one method. Complementary and alternative medicine use is more common in cases of advanced disease or poor prognosis. This is a descriptive study of complementary and alternative medicine. This study was conducted in the Chemotherapy Unit at Ondokuz Mayıs University, Faculty of Medicine, Samsun, Turkey, between 18 March 2008-30 June 2008. Two hundred fifty-three patients with cancer, among 281 patients who applied to the chemotherapy clinic between these dates, agreed to take part in the study with whom contact could be made were included. A questionnaire including descriptive characteristics in collecting data, characteristics about diseases and their treatments, complementary and alternative medicine information and implementation situations and a control list about complementary and alternative medicine implementations were given. The collected data were evaluated by computer using descriptive statistics, the chi-square test and Student's t-test. In this study, 94·1% of the patients were content with medical treatment, 58·9% of them used complementary and alternative medicine treatments, 41·1% did not use any complementary and alternative medicine treatments. The satisfaction level of the patients with complementary and alternative medicine methods was slightly above mediocre (2·33 SD 0·64, on a scale of 1-3). The average cost per capita spent by the patients using complementary and alternative medicine for all the different methods was US$288·26. It was determined that although patients did not have enough knowledge about complementary and alternative medicine methods, the prevalence of complementary and alternative medicine and satisfaction levels are high that complementary and alternative medicine users spend substantial sums of money for these methods. To sustain medical treatment and prognosis of cancer, it is important for nurses to consult with their patients regarding the use and potential risks of some complementary and alternative medicine. © 2011 Blackwell Publishing Ltd.

Prevalence and determinants of use of complementary and alternative medicine by hypertensive patients attending primary health care facilities in Kinshasa, Democratic Republic of the Congo: a cross-sectional study.

PubMed

Lulebo, Aimée M; Mapatano, Mala A; Mutombo, Paulin B; Mafuta, Eric M; Samba, Gédéon; Coppieters, Yves

2017-04-08

In the Democratic Republic of the Congo the control of hypertension is poor, characterized by an increasing number of reported cases of hypertension related complications. Poor control of hypertension is associated with non-adherence to antihypertensive medication. It is well established that the use of complementary and alternative medicine is one of the main factors of non-adherence to antihypertensive medication. The aim of this study is to determine the prevalence and factors associated with the use of complementary and alternative medicine. A cross-sectional study was carried out at the Kinshasa Primary Health-care (KPHC) facilities network in November 2014. A structured interview questionnaire was administrated to a total of 280hypertensive patients. Complementary and alternative medicine were defined according to the National Institute of Health classification as a group of diverse medical and healthcare systems, practices, and products that are not presently considered to be part of conventional medicine. Data were summarized using proportion and mean (with standard deviation). The student's t test and χ 2 test were used respectively for mean and proportion comparison. Logistic regression analysis identified determinants of the use of complementary and alternative medicine. The prevalence of use of complementary and alternative medicine was 26.1% (95% CI: 20.7% - 31.8%).Determinants of use of complementary and alternative medicine included misperception about hypertension curability (OR = 2.1; 95%CI: 1.1-3.7) and experience of medication side effects (OR = 2.9; 95%CI: 1.7-5.1). The use of CAM for hypertensive patients is a major problem; antihypertensives with fewer side effects must be emphasized. Religious leaders must become involved in the communication for behavioral change activities to improve the quality of life for hypertensive patients.

Maternal provision of non-sex-specific transformer messenger RNA in sex determination of the wasp Asobara tabida.

PubMed

Geuverink, E; Verhulst, E C; van Leussen, M; van de Zande, L; Beukeboom, L W

2018-02-01

In many insect species maternal provision of sex-specifically spliced messenger RNA (mRNA) of sex determination genes is an essential component of the sex determination mechanism. In haplodiploid Hymenoptera, maternal provision in combination with genomic imprinting has been shown for the parasitoid Nasonia vitripennis, known as maternal effect genomic imprinting sex determination (MEGISD). Here, we characterize the sex determination cascade of Asobara tabida, another hymenopteran parasitoid. We show the presence of the conserved sex determination genes doublesex (dsx), transformer (tra) and transformer-2 (tra2) orthologues in As. tabida. Of these, At-dsx and At-tra are sex-specifically spliced, indicating a conserved function in sex determination. At-tra and At-tra2 mRNA is maternally provided to embryos but, in contrast to most studied insects, As. tabida females transmit a non-sex-specific splice form of At-tra mRNA to the eggs. In this respect, As. tabida sex determination differs from the MEGISD mechanism. How the paternal genome can induce female development in the absence of maternal provision of sex-specifically spliced mRNA remains an open question. Our study reports a hitherto unknown variant of maternal effect sex determination and accentuates the diversity of insect sex determination mechanisms. © 2017 The Authors. Insect Molecular Biology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.

Maintenance of polygenic sex determination in a fluctuating environment: an individual-based model.

PubMed

Bateman, A W; Anholt, B R

2017-05-01

R. A. Fisher predicted that individuals should invest equally in offspring of both sexes, and that the proportion of males and females produced (the primary sex ratio) should evolve towards 1:1 when unconstrained. For many species, sex determination is dependent on sex chromosomes, creating a strong tendency for balanced sex ratios, but in other cases, multiple autosomal genes interact to determine sex. In such cases, the maintenance of multiple sex-determining alleles at multiple loci and the consequent among-family variability in sex ratios presents a puzzle, as theory predicts that such systems should be unstable. Theory also predicts that environmental influences on sex can complicate outcomes of genetic sex determination, and that population structure may play a role. Tigriopus californicus, a copepod that lives in splash-pool metapopulations and exhibits polygenic and environment-dependent sex determination, presents a test case for relevant theory. We use this species as a model for parameterizing an individual-based simulation to investigate conditions that could maintain polygenic sex determination. We find that metapopulation structure can delay the degradation of polygenic sex determination and that periods of alternating frequency-dependent selection, imposed by seasonal fluctuations in environmental conditions, can maintain polygenic sex determination indefinitely. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

[Elucidation of key genes in sex determination in genetics teaching].

PubMed

Li, Meng; He, Zhumei

2014-06-01

Sex is an important and complex feature of organisms, which is controlled by the genetic and environmental factors. The genetic factors, i.e., genes, are vital in sex determination. However, not all the related genes play the same roles, and some key genes play a vital role in the sex determination and differentiation. With the development of the modern genetics, a great progress on the key genes has been made in sex determination. In this review, we summarize the mechanism of sex determination and the strategy of how to study the key genes in sex determination. It will help us to understand the mechanism of sex determination better in the teaching of genetics.

The end of gonad-centric sex determination in mammals

PubMed Central

Arnold, Arthur P.

2011-01-01

The 20th century theory of mammalian sex determination states that the embryo is sexually indifferent until the differentiation of gonads, after which sex differences in phenotype are caused by differential effects of gonadal hormones. That theory is inadequate because some sex differences precede differentiation of the gonads and/or are determined by non-gonadal effects of the sexual inequality in number and type of sex chromosomes. A general theory of sex determination is proposed, which recognizes multiple parallel primary sex-determining pathways initiated by genes or factors encoded by the sex chromosomes. The separate sex-specific pathways interact to synergize with or antagonize each other, enhancing or reducing sex differences in phenotype. PMID:22078126

Medicinal Plants Used by Traditional Healers in Sangurur, Elgeyo Marakwet County, Kenya

PubMed Central

Kigen, Gabriel; Kipkore, Wilson; Wanjohi, Bernard; Haruki, Boniface; Kemboi, Jemutai

2017-01-01

Background: Although herbal medical products are still widely used in Kenya, many of the medicinal plants used by traditional medical practitioners (TMPs) have not been documented, despite several challenges that are now threatening the sustainability of the practice. Objective: To document the medicinal plants and healing methods used by TMPs in a region of Kenya with several recognized herbalists for potential research. Materials and Methods: Semi-structured interviews, group discussions, and direct observations were used to collect ethnopharmacological information. The participant's bio-data, clinical conditions treated, methods of treatment, medicinal plants used, methods of preparation and administration, and dosage forms were recorded. Results: A total of 99 medicinal plants and 12 complementary preparations employed in the treatment of 64 medical conditions were identified. The most widely used plant was Rotala tenella which was used to treat nine medicinal conditions; seven each for Aloe tweediae and Dovyalis abyssinica; and six each for Basella alba and Euclea divinorum. The plants belonged to 55 families with Fabaceae family being the most frequently used (10), followed by Apocynaceae and Solanaceae, each with six species, respectively. We identified plants used to determine the sex of an unborn baby and those used to treat several conditions including anthrax and cerebral malaria and herbs used to detoxify meat from an animal that has died from anthrax. Of special interest was R. tenella which is used to prevent muscle injury. Conclusions: We have documented several plants with potential therapeutic effects. Further research may be conducted to determine their efficacy. SUMMARY The medicinal plants used by traditional healers in a community which still practices herbal medicine in Kenya were documented. A total of 99 medicinal plants and 12 complementary preparations employed in the treatment of 64 medical conditions were identified. Further research may be carried out in order to determine their therapeutic efficacies. Abbreviations Used: Fic: Informant consensus factor, Nur: Number of use reports in each category, Ns: Number of reported species, TMPs: Traditional medical practitioners. PMID:29263626

Medicinal Plants Used by Traditional Healers in Sangurur, Elgeyo Marakwet County, Kenya.

PubMed

Kigen, Gabriel; Kipkore, Wilson; Wanjohi, Bernard; Haruki, Boniface; Kemboi, Jemutai

2017-01-01

Although herbal medical products are still widely used in Kenya, many of the medicinal plants used by traditional medical practitioners (TMPs) have not been documented, despite several challenges that are now threatening the sustainability of the practice. To document the medicinal plants and healing methods used by TMPs in a region of Kenya with several recognized herbalists for potential research. Semi-structured interviews, group discussions, and direct observations were used to collect ethnopharmacological information. The participant's bio-data, clinical conditions treated, methods of treatment, medicinal plants used, methods of preparation and administration, and dosage forms were recorded. A total of 99 medicinal plants and 12 complementary preparations employed in the treatment of 64 medical conditions were identified. The most widely used plant was Rotala tenella which was used to treat nine medicinal conditions; seven each for Aloe tweediae and Dovyalis abyssinica ; and six each for Basella alba and Euclea divinorum . The plants belonged to 55 families with Fabaceae family being the most frequently used (10), followed by Apocynaceae and Solanaceae, each with six species, respectively. We identified plants used to determine the sex of an unborn baby and those used to treat several conditions including anthrax and cerebral malaria and herbs used to detoxify meat from an animal that has died from anthrax. Of special interest was R. tenella which is used to prevent muscle injury. We have documented several plants with potential therapeutic effects. Further research may be conducted to determine their efficacy. The medicinal plants used by traditional healers in a community which still practices herbal medicine in Kenya were documented. A total of 99 medicinal plants and 12 complementary preparations employed in the treatment of 64 medical conditions were identified. Further research may be carried out in order to determine their therapeutic efficacies. Abbreviations Used: F ic : Informant consensus factor, N ur : Number of use reports in each category, N s : Number of reported species, TMPs: Traditional medical practitioners.

Optimization of the nutrient content and protein quality of cereal-legume blends for use as complementary foods in Ghana.

PubMed

Suri, Devika J; Tano-Debrah, Kwaku; Ghosh, Shibani A

2014-09-01

Nutritionally adequate complementary foods made from locally available ingredients are of high priority in developing countries, including Ghana. The majority of complementary foods in these countries are cereal-based and are unable to meet the nutrient intakes recommended by the World Health Organization. To evaluate the nutrient content and protein quality of local cereal-legume blends for complementary foods against recommendations and to determine the quantities of additional ingredients required to meet needs by using linear programming. Nine cereal-legume combinations (maize, sorghum, or millet combined with cowpea, peanut, or soybean) and koko (a traditional Ghanaian maize-based complementary food) were evaluated based on the macronutrient targets for a daily ration of complementary food for the age group 12 to 24 months: 264 kcal, 6.5 g of protein, and 8.2 to 11.7 g of fat. Protein quality was assessed by the Protein Digestibility Corrected Amino Acid Score (PDCAAS). Linear programming was then used to determine the amounts of additional oil, sugar, and lysine needed to meet macronutrient requirements. No traditional cereal-legume food met all complementary food macronutrient requirements on its own. Cereal-legume blends made with peanut or cowpeas were low in quality protein, while those with soybean were low in fat. Lysine was the limiting amino acid (PDCAAS 0.50 to 0.82) in all blends. Adding lysine increased utilizable protein by 1% to 10% in soybean blends, 35% to 40% in peanut blends, and 14% to 24% in cowpea blends. Peanut-maize, peanut-millet, and all soybean-cereal blends were able to meet macronutrient targets; most micronutrients remained below recommended levels. Traditional cereal-legume blends made from locally available ingredients do not meet energy, quality protein, and fat recommendations for complementary foods; however, such complementary food blends may be optimized to meet nutrient requirements by using linear programming as a tool to determine the exact levels of fortificants to be added (including, but not limited to, added fat, amino acids, and micronutrients).

A new species of Piaroa (Schizomida: Hubbardiidae) from Venezuela, with taxonomic notes on the genus.

PubMed

M, Osvaldo Villarreal; De Armas, Luis F; García, Luis Fernando

2014-02-19

A new species belonging to the schizomid genus Piaroa Villarreal, Giupponi and Tourinho, 2008 is described from north-western Venezuela. A complementary description of Piaroa guipongai Villarreal and Garcia, 2012 is provided including SEM pictures of relevant structures of both sexes. A key for males of Piaroa and Colombiazomus Armas and Delgado-Santa, 2012 is included. The presence of Dm3 setae on Hubbardiidae is discussed.

Field study suggests that sex determination in sea lamprey is directly influenced by larval growth rate.

PubMed

Johnson, Nicholas S; Swink, William D; Brenden, Travis O

2017-03-29

Sex determination mechanisms in fishes lie along a genetic-environmental continuum and thereby offer opportunities to understand how physiology and environment interact to determine sex. Mechanisms and ecological consequences of sex determination in fishes are primarily garnered from teleosts, with little investigation into basal fishes. We tagged and released larval sea lamprey ( Petromyzon marinus ) into unproductive lake and productive stream environments. Sex ratios produced from these environments were quantified by recapturing tagged individuals as adults. Sex ratios from unproductive and productive environments were initially similar. However, sex ratios soon diverged, with unproductive environments becoming increasingly male-skewed and productive environments becoming less male-skewed with time. We hypothesize that slower growth in unproductive environments contributed to the sex ratio differences by directly influencing sex determination. To the best of our knowledge, this is the first study suggesting that growth rate in a fish species directly influences sex determination; other studies have suggested that the environmental variables to which sex determination is sensitive (e.g. density, temperature) act as cues for favourable or unfavourable growth conditions. Understanding mechanisms of sex determination in lampreys may provide unique insight into the underlying principles of sex determination in other vertebrates and provide innovative approaches for their management where valued and invasive. © 2017 The Author(s).

Field study suggests that sex determination in sea lamprey is directly influenced by larval growth rate

USGS Publications Warehouse

Johnson, Nicholas; Swink, William D.; Brenden, Travis O.

2017-01-01

Sex determination mechanisms in fishes lie along a genetic-environmental continuum and thereby offer opportunities to understand how physiology and environment interact to determine sex. Mechanisms and ecological consequences of sex determination in fishes are primarily garnered from teleosts, with little investigation into basal fishes. We tagged and released larval sea lamprey (Petromyzon marinus) into unproductive lake and productive stream environments. Sex ratios produced from these environments were quantified by recapturing tagged individuals as adults. Sex ratios from unproductive and productive environments were initially similar. However, sex ratios soon diverged, with unproductive environments becoming increasingly male-skewed and productive environments becoming less male-skewed with time. We hypothesize that slower growth in unproductive environments contributed to the sex ratio differences by directly influencing sex determination. To the best of our knowledge, this is the first study suggesting that growth rate in a fish species directly influences sex determination; other studies have suggested that the environmental variables to which sex determination is sensitive (e.g. density, temperature) act as cues for favourable or unfavourable growth conditions. Understanding mechanisms of sex determination in lampreys may provide unique insight into the underlying principles of sex determination in other vertebrates and provide innovative approaches for their management where valued and invasive.

Characterization of Pisrt1/Foxl2 in Ellobius lutescens and exclusion as sex-determining genes.

PubMed

Baumstark, Annette; Hameister, Horst; Hakhverdyan, Mikhayil; Bakloushinskaya, Irina; Just, Walter

2005-04-01

The rodent Ellobius lutescens is an exceptional mammal which determines male sex constitutively without the SRY gene and, therefore, may serve as an animal model for human 46,XX female-to-male sex reversal. It was suggested that other factors of the network of sex-determining genes determine maleness in these animals. However, some sex-determining genes like SOX9 and SF1 have already been excluded by segregation analysis as primary sex-determining factors in E. lutescens. In this work, we have cloned and characterized two genes of the PIS (polled intersex syndrome) gene interval, which were reported as candidates in female-to-male sex reversal in hornless goats recently. The genes Foxl2 and Pisrt1 from that interval were identified in E. lutescens DNA and mapped to Chromosome 8. We have excluded linkage of Foxl2 and Pisrt1 loci with the sex of the animals. Hence, the involvement of this gene region in sex determination may be specific for goats and is not a general mechanism of XX sex reversal or XX male sex determination.

The Variety of Vertebrate Mechanisms of Sex Determination

PubMed Central

Trukhina, Antonina V.; Lukina, Natalia A.; Wackerow-Kouzova, Natalia D.; Smirnov, Alexander F.

2013-01-01

The review deals with features of sex determination in vertebrates. The mechanisms of sex determination are compared between fishes, amphibians, reptilians, birds, and mammals. We focus on structural and functional differences in the role of sex-determining genes in different vertebrates. Special attention is paid to the role of estrogens in sex determination in nonmammalian vertebrates. PMID:24369014

The variety of vertebrate mechanisms of sex determination.

PubMed

Trukhina, Antonina V; Lukina, Natalia A; Wackerow-Kouzova, Natalia D; Smirnov, Alexander F

2013-01-01

The review deals with features of sex determination in vertebrates. The mechanisms of sex determination are compared between fishes, amphibians, reptilians, birds, and mammals. We focus on structural and functional differences in the role of sex-determining genes in different vertebrates. Special attention is paid to the role of estrogens in sex determination in nonmammalian vertebrates.

Transitions in sex determination and sex chromosomes across vertebrate species.

PubMed

Pennell, Matthew W; Mank, Judith E; Peichel, Catherine L

2018-02-16

Despite the prevalence of sexual reproduction across eukaryotes, there is a remarkable diversity of sex-determination mechanisms. The underlying causes of this diversity remain unclear, and it is unknown whether there are convergent trends in the directionality of turnover in sex-determination mechanisms. We used the recently assembled Tree of Sex database to assess patterns in the evolution of sex-determination systems in the remarkably diverse vertebrate clades of teleost fish, squamate reptiles and amphibians. Contrary to theoretical predictions, we find no evidence that the evolution of separate sexes is irreversible, as transitions from separate sexes to hermaphroditism occur at higher rates than the reverse in fish. We also find that transitions from environmental sex determination to genetic sex determination occur at higher rates than the reverse in both squamates and fish, suggesting that genetic sex determination is more stable. However, our data are not consistent with the hypothesis that heteromorphic sex chromosomes are an "evolutionary trap." Rather, we find similar transition rates between homomorphic and heteromorphic sex chromosomes in both fish and amphibians, and to environmental sex determination from heteromorphic vs. homomorphic sex chromosome systems in fish. Finally, we find that transitions between male and female heterogamety occur at similar rates in amphibians and squamates, while transitions to male heterogamety occur at higher rates in fish. Together, these results provide the most comprehensive view to date of the evolution of vertebrate sex determination in a phylogenetic context, providing new insight into long-standing questions about the evolution of sexual reproduction. © 2018 John Wiley & Sons Ltd.

What was the ancestral sex-determining mechanism in amniote vertebrates?

PubMed

Johnson Pokorná, Martina; Kratochvíl, Lukáš

2016-02-01

Amniote vertebrates, the group consisting of mammals and reptiles including birds, possess various mechanisms of sex determination. Under environmental sex determination (ESD), the sex of individuals depends on the environmental conditions occurring during their development and therefore there are no sexual differences present in their genotypes. Alternatively, through the mode of genotypic sex determination (GSD), sex is determined by a sex-specific genotype, i.e. by the combination of sex chromosomes at various stages of differentiation at conception. As well as influencing sex determination, sex-specific parts of genomes may, and often do, develop specific reproductive or ecological roles in their bearers. Accordingly, an individual with a mismatch between phenotypic (gonadal) and genotypic sex, for example an individual sex-reversed by environmental effects, should have a lower fitness due to the lack of specialized, sex-specific parts of their genome. In this case, evolutionary transitions from GSD to ESD should be less likely than transitions in the opposite direction. This prediction contrasts with the view that GSD was the ancestral sex-determining mechanism for amniote vertebrates. Ancestral GSD would require several transitions from GSD to ESD associated with an independent dedifferentiation of sex chromosomes, at least in the ancestors of crocodiles, turtles, and lepidosaurs (tuataras and squamate reptiles). In this review, we argue that the alternative theory postulating ESD as ancestral in amniotes is more parsimonious and is largely concordant with the theoretical expectations and current knowledge of the phylogenetic distribution and homology of sex-determining mechanisms. © 2014 Cambridge Philosophical Society.

The evolution of the search for novel genes in mammalian sex determination: from mice to men.

PubMed

Arboleda, Valerie A; Vilain, Eric

2011-01-01

Disorders of sex determination are a genetically heterogeneous group of rare disorders, presenting with sex-specific phenotypes and variable expressivity. Prior to the advent of the Human Genome Project, the identification of novel mammalian sex determination genes was hindered by the rarity of disorders of sex determination and small family sizes that made traditional linkage approaches difficult, if not impossible. This article reviews the revolutionary role of the Human Genome Project in the history of sex determination research and highlights the important role of inbred mouse models in elucidating the role of identified sex determination genes in mammalian sex determination. Next generation sequencing technologies has made it possible to sequence complete human genomes or exomes for the purpose of providing a genetic diagnosis to more patients with unexplained disorders of sex determination and identifying novel sex determination genes. However, beyond novel gene discovery, these tools have the power to inform us on more intricate and complex regulation-taking place within the heterogeneous cells that make up the testis and ovary. Copyright © 2011 Elsevier Inc. All rights reserved.

Molecular evolution of Dmrt1 accompanies change of sex-determining mechanisms in reptilia.

PubMed

Janes, Daniel E; Organ, Christopher L; Stiglec, Rami; O'Meally, Denis; Sarre, Stephen D; Georges, Arthur; Graves, Jennifer A M; Valenzuela, Nicole; Literman, Robert A; Rutherford, Kim; Gemmell, Neil; Iverson, John B; Tamplin, Jeffrey W; Edwards, Scott V; Ezaz, Tariq

2014-12-01

In reptiles, sex-determining mechanisms have evolved repeatedly and reversibly between genotypic and temperature-dependent sex determination. The gene Dmrt1 directs male determination in chicken (and presumably other birds), and regulates sex differentiation in animals as distantly related as fruit flies, nematodes and humans. Here, we show a consistent molecular difference in Dmrt1 between reptiles with genotypic and temperature-dependent sex determination. Among 34 non-avian reptiles, a convergently evolved pair of amino acids encoded by sequence within exon 2 near the DM-binding domain of Dmrt1 distinguishes species with either type of sex determination. We suggest that this amino acid shift accompanied the evolution of genotypic sex determination from an ancestral condition of temperature-dependent sex determination at least three times among reptiles, as evident in turtles, birds and squamates. This novel hypothesis describes the evolution of sex-determining mechanisms as turnover events accompanied by one or two small mutations. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Molecular evolution of Dmrt1 accompanies change of sex-determining mechanisms in reptilia

PubMed Central

Janes, Daniel E.; Organ, Christopher L.; Stiglec, Rami; O'Meally, Denis; Sarre, Stephen D.; Georges, Arthur; Graves, Jennifer A. M.; Valenzuela, Nicole; Literman, Robert A.; Rutherford, Kim; Gemmell, Neil; Iverson, John B.; Tamplin, Jeffrey W.; Edwards, Scott V.; Ezaz, Tariq

2014-01-01

In reptiles, sex-determining mechanisms have evolved repeatedly and reversibly between genotypic and temperature-dependent sex determination. The gene Dmrt1 directs male determination in chicken (and presumably other birds), and regulates sex differentiation in animals as distantly related as fruit flies, nematodes and humans. Here, we show a consistent molecular difference in Dmrt1 between reptiles with genotypic and temperature-dependent sex determination. Among 34 non-avian reptiles, a convergently evolved pair of amino acids encoded by sequence within exon 2 near the DM-binding domain of Dmrt1 distinguishes species with either type of sex determination. We suggest that this amino acid shift accompanied the evolution of genotypic sex determination from an ancestral condition of temperature-dependent sex determination at least three times among reptiles, as evident in turtles, birds and squamates. This novel hypothesis describes the evolution of sex-determining mechanisms as turnover events accompanied by one or two small mutations. PMID:25540158

Patterns and Mechanisms of Evolutionary Transitions between Genetic Sex-Determining Systems

PubMed Central

Sander van Doorn, G.

2014-01-01

The diversity and patchy phylogenetic distribution of genetic sex-determining mechanisms observed in some taxa is thought to have arisen by the addition, modification, or replacement of regulators at the upstream end of the sex-determining pathway. Here, I review the various evolutionary forces acting on upstream regulators of sexual development that can cause transitions between sex-determining systems. These include sex-ratio selection and pleiotropic benefits, as well as indirect selection mechanisms involving sex-linked sexually antagonistic loci or recessive deleterious mutations. Most of the current theory concentrates on the population–genetic aspects of sex-determination transitions, using models that do not reflect the developmental mechanisms involved in sex determination. However, the increasing availability of molecular data creates opportunities for the development of mechanistic models that can clarify how selection and developmental architecture interact to direct the evolution of sex-determination genes. PMID:24993578

Use of Alternative and Complementary Medicine in Patients with Malignant Diseases in High-Volume Cancer Center and Future Aspects

PubMed

Kust, Davor; Šamija, Ivan; Marić-Brozić, Jasmina; Svetec, Branka; Miletić, Marija; Mamić, Gordana; Bolanča, Ante; Kusić, Zvonko; Fröbe, Ana

2016-12-01

Usage of complementary and alternative medicine (CAM) is steadily increasing over the last decades, gaining medical, economic and sociological importance. The aim of the present study was to assess the use of complementary and alternative therapies in cancer patients. A cross-sectional, descriptive survey design was used to collect data through an anonymous questionnaire. A total of 267 patients were included in the study. The prevalence of CAM use among cancer patients in this study was 60.3%. It was found that 61 heterogeneous CAM therapies were used, the most popular among patients being naturopathy/folk medicine. In multivariate logistic regression analysis, independent predictors of CAM use were high income, divorced status, female sex and younger age. In conclusion, considering the fact that a large proportion of patients used at least one CAM approach, we need to continue our efforts to improve the patient-oncologist communication in order to deliver most reliable information to patients and to better understand the possible standard medicine-CAM interactions. According to results of the latest studies, CAM therapies that help manage pain, nausea, fatigue, anxiety, and other symptoms should be integrated into the patient overall care.

Polygenic sex determination in the cichlid fish Astatotilapia burtoni.

PubMed

Roberts, Natalie B; Juntti, Scott A; Coyle, Kaitlin P; Dumont, Bethany L; Stanley, M Kaitlyn; Ryan, Allyson Q; Fernald, Russell D; Roberts, Reade B

2016-10-26

The East African riverine cichlid species Astatotilapia burtoni serves as an important laboratory model for sexually dimorphic physiology and behavior, and also serves as an outgroup species for the explosive adaptive radiations of cichlid species in Lake Malawi and Lake Victoria. An astounding diversity of genetic sex determination systems have been revealed within the adaptive radiation of East African cichlids thus far, including polygenic sex determination systems involving the epistatic interaction of multiple, independently segregating sex determination alleles. However, sex determination has remained unmapped in A. burtoni. Here we present mapping results supporting the presence of multiple, novel sex determination alleles, and thus the presence of polygenic sex determination in A. burtoni. Using mapping in small families in conjunction with restriction-site associated DNA sequencing strategies, we identify associations with sex at loci on linkage group 13 and linkage group 5-14. Inheritance patterns support an XY sex determination system on linkage group 5-14 (a chromosome fusion relative to other cichlids studied), and an XYW system on linkage group 13, and these associations are replicated in multiple families. Additionally, combining our genetic data with comparative genomic analysis identifies another fusion that is unassociated with sex, with linkage group 8-24 and linkage group 16-21 fused in A. burtoni relative to other East African cichlid species. We identify genetic signals supporting the presence of three previously unidentified sex determination alleles at two loci in the species A. burtoni, strongly supporting the presence of polygenic sex determination system in the species. These results provide a foundation for future mapping of multiple sex determination genes and their interactions. A better understanding of sex determination in A. burtoni provides important context for their use in behavioral studies, as well as studies of the evolution of genetic sex determination and sexual conflicts in East African cichlids.

Sex Unleashes Your Tongue: Sexual Priming Motivates Self-Disclosure to a New Acquaintance and Interest in Future Interactions.

PubMed

Birnbaum, Gurit E; Mizrahi, Moran; Kaplan, Ayelet; Kadosh, Danielle; Kariv, Dana; Tabib, Danielle; Ziv, Daniella; Sadeh, Lihi; Burban, Daniella

2017-05-01

Research has demonstrated the contribution of sexual activity to the quality of ongoing relationships. Nevertheless, less attention has been given to how activation of the sexual system affects relationship-initiation processes. Three studies used complementary methodologies to examine the effect of sexual priming on self-disclosure, a relationship-promoting behavior. In Study 1, participants were subliminally exposed to sexual stimuli (vs. neutral stimuli), and then disclosed over Instant Messenger a personal event to an opposite-sex stranger. Results showed that merely thinking about sex, even without being aware of it, encouraged self-disclosure. Study 2 replicated these findings in relatively naturalistic conditions (live face-to-face interactions following supraliminal video priming). Study 3 extended these findings, indicating that sexual priming facilitated self-disclosure, which, in turn, increased interest in future interactions with the stranger. Together, these findings suggest that activation of the sexual system encourages the use of strategies that allow people to become closer to potential partners.

On the origin of sex chromosomes from meiotic drive.

PubMed

Úbeda, Francisco; Patten, Manus M; Wild, Geoff

2015-01-07

Most animals and many plants make use of specialized chromosomes (sex chromosomes) to determine an individual's sex. Best known are the XY and ZW sex-determination systems. Despite having evolved numerous times, sex chromosomes present something of an evolutionary puzzle. At their origin, alleles that dictate development as one sex or the other (primitive sex chromosomes) face a selective penalty, as they will be found more often in the more abundant sex. How is it possible that primitive sex chromosomes overcome this disadvantage? Any theory for the origin of sex chromosomes must identify the benefit that outweighs this cost and enables a sex-determining mutation to establish in the population. Here we show that a new sex-determining allele succeeds when linked to a sex-specific meiotic driver. The new sex-determining allele benefits from confining the driving allele to the sex in which it gains the benefit of drive. Our model requires few special assumptions and is sufficiently general to apply to the evolution of sex chromosomes in outbreeding cosexual or dioecious species. We highlight predictions of the model that can discriminate between this and previous theories of sex-chromosome origins. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

On the origin of sex chromosomes from meiotic drive

PubMed Central

Úbeda, Francisco; Patten, Manus M.; Wild, Geoff

2015-01-01

Most animals and many plants make use of specialized chromosomes (sex chromosomes) to determine an individual's sex. Best known are the XY and ZW sex-determination systems. Despite having evolved numerous times, sex chromosomes present something of an evolutionary puzzle. At their origin, alleles that dictate development as one sex or the other (primitive sex chromosomes) face a selective penalty, as they will be found more often in the more abundant sex. How is it possible that primitive sex chromosomes overcome this disadvantage? Any theory for the origin of sex chromosomes must identify the benefit that outweighs this cost and enables a sex-determining mutation to establish in the population. Here we show that a new sex-determining allele succeeds when linked to a sex-specific meiotic driver. The new sex-determining allele benefits from confining the driving allele to the sex in which it gains the benefit of drive. Our model requires few special assumptions and is sufficiently general to apply to the evolution of sex chromosomes in outbreeding cosexual or dioecious species. We highlight predictions of the model that can discriminate between this and previous theories of sex-chromosome origins. PMID:25392470

Temperature, Genes, and Sex: a Comparative View of Sex Determination in Trachemys scripta and Mus musculus

PubMed Central

Yao, Humphrey H-C; Capel, Blanche

2014-01-01

Sex determination, the step at which differentiation of males and females is initiated in the embryo, is of central importance to the propagation of species. There is a remarkable diversity of mechanisms by which sex determination is accomplished. In general these mechanisms fall into two categories: Genetic Sex Determination (GSD), which depends on genetic differences between the sexes, and Environmental Sex Determination (ESD), which depends on extrinsic cues. In this review we will consider these two means of determining sex with particular emphasis on two species: a species that depends on GSD, Mus musculus, and a species that depends on ESD, Trachemys scripta. Because the structural organization of the adult testis and ovary is very similar across vertebrates, most biologists had expected that the pathways downstream of the sex-determining switch would be conserved. However, emerging data indicate that not only are the initial sex determining mechanisms different, but the downstream pathways and morphogenetic events leading to the development of a testis or ovary also are different. PMID:16046442

The battle of the sexes over seed size: support for both kinship genomic imprinting and interlocus contest evolution.

PubMed

Willi, Yvonne

2013-06-01

Outcrossing creates a venue for parental conflict. When one sex provides parental care to offspring fertilized by several partners, the nonproviding sex is under selection to maximally exploit the caring sex. The caring sex may counteradapt, and a coevolutionary arms race ensues. Genetic models of this conflict include the kinship theory of genomic imprinting (parent-of-origin-specific expression of maternal-care effectors) and interlocus conflict evolution (interaction between male selfish signals and female abatement). Predictions were tested by measuring the sizes of seeds produced by within-population crosses (diallel design) and between-population crosses in outcrossing and selfing populations of Arabidopsis lyrata. Within-population diallel crosses revealed substantial maternal variance in seed size in most populations. The comparison of between- and within-population crosses showed that seeds were larger when pollen came from another outcrossing population than when pollen came from a selfing or the same population, supporting interlocus contest evolution between male selfish genes and female recognition genes. Evidence for kinship genomic imprinting came from complementary trait means of seed size in reciprocal between-population crosses independent of whether populations were predominantly selfing or outcrossing. Hence, both kinship genomic imprinting and interlocus contest are supported in outcrossing Arabidopsis, whereas only kinship genomic imprinting is important in selfing populations.

Use of complementary and alternative medicine in head and neck cancer patients.

PubMed

Lim, C M; Ng, A; Loh, K S

2010-05-01

To determine the prevalence and profile of patients who use complementary and alternative medicine, within a cohort of head and neck cancer patients. Cross-sectional survey. Ninety-three consecutive head and neck cancer patients being followed up at the department of otolaryngology head and neck surgery were surveyed using an interviewer-administered questionnaire. The prevalence of complementary and alternative medicine use was 67.8 per cent. Patients who used complementary and alternative medicine were more likely to be female, better educated and younger, compared with non-users. A total of 82.5 per cent (52/63) perceived complementary and alternative medicine to be effective, even though they were aware of the lack of research and endorsement by their physician regarding such medicine. The use of complementary and alternative medicine by head and neck cancer patients is common, regardless of efficacy or cost. Clinicians should routinely ask patients about their use of complementary and alternative medicine, to facilitate communication and enable appropriate use of such medicine.

Developing an Empirical Test of the Impact of Vouchers on Elasticity of Demand for Post-Secondary Education and on the Financing of Higher Education; and Economic Efficiency in Post-Secondary Education. Final Project Report.

ERIC Educational Resources Information Center

Newton, Jan N.; And Others

Two separate NIE research projects in higher education, closely related in substance and complementary, were undertaken in Oregon in 1973-75. During the first year, the objectives were to: (1) compute and analyze various configurations of student schooling costs and financial resources according to institutional type and to student sex and…

Identification of the sex-determining locus in grass puffer (Takifugu niphobles) provides evidence for sex-chromosome turnover in a subset of Takifugu species

PubMed Central

Atsumi, Kazufumi; Kamiya, Takashi; Nozawa, Aoi; Aoki, Yuma; Tasumi, Satoshi; Koyama, Takashi; Nakamura, Osamu; Suzuki, Yuzuru

2018-01-01

There is increasing evidence for frequent turnover in sex chromosomes in vertebrates. Yet experimental systems suitable for tracing the detailed process of turnover are rare. In theory, homologous turnover is possible if the new sex-determining locus is established on the existing sex-chromosome. However, there is no empirical evidence for such an event. The genus Takifugu includes fugu (Takifugu rubripes) and its two closely-related species whose sex is most likely determined by a SNP at the Amhr2 locus. In these species, males are heterozygous, with G and C alleles at the SNP site, while females are homozygous for the C allele. To determine if a shift in the sex-determining locus occurred in another member of this genus, we used genetic mapping to characterize the sex-chromosome systems of Takifugu niphobles. We found that the G allele of Amhr2 is absent in T. niphobles. Nevertheless, our initial mapping suggests a linkage between the phenotypic sex and the chromosome 19, which harbors the Amhr2 locus. Subsequent high-resolution analysis using a sex-reversed fish demonstrated that the sex-determining locus maps to the proximal end of chromosome 19, far from the Amhr2 locus. Thus, it is likely that homologous turnover involving these species has occurred. The data also showed that there is a male-specific reduction of recombination around the sex-determining locus. Nevertheless, no evidence for sex-chromosome differentiation was detected: the reduced recombination depended on phenotypic sex rather than genotypic sex; no X- or Y-specific maker was obtained; the YY individual was viable. Furthermore, fine-scale mapping narrowed down the new sex-determining locus to the interval corresponding to approximately 300-kb of sequence in the fugu genome. Thus, T. niphobles is determined to have a young and small sex-determining region that is suitable for studying an early phase of sex-chromosome evolution and the mechanisms underlying turnover of sex chromosome. PMID:29293639

Identification of Sex-determining Loci in Pacific White Shrimp Litopeneaus vannamei Using Linkage and Association Analysis.

PubMed

Yu, Yang; Zhang, Xiaojun; Yuan, Jianbo; Wang, Quanchao; Li, Shihao; Huang, Hao; Li, Fuhua; Xiang, Jianhai

2017-06-01

The Pacific white shrimp Litopenaeus vannamei is a predominant aquaculture shrimp species in the world. Like other animals, the L. vannamei exhibited sexual dimorphism in growth trait. Mapping of the sex-determining locus will be very helpful to clarify the sex determination system and further benefit the shrimp aquaculture industry towards the production of mono-sex stocks. Based on the data used for high-density linkage map construction, linkage-mapping analysis was conducted. The sex determination region was mapped in linkage group (LG) 18. A large region from 0 to 21.205 cM in LG18 showed significant association with sex. However, none of the markers in this region showed complete association with sex in the other populations. So an association analysis was designed using the female parent, pool of female progenies, male parent, and pool of male progenies. Markers were de novo developed and those showing significant differences between female and male pools were identified. Among them, three sex-associated markers including one fully associated marker were identified. Integration of linkage and association analysis showed that the sex determination region was fine-mapped in a small region along LG18. The identified sex-associated marker can be used for the sex detection of this species at genetic level. The fine-mapped sex-determining region will contribute to the mapping of sex-determining gene and help to clarify sex determination system for L. vannamei.

Sex determination in insects: a binary decision based on alternative splicing.

PubMed

Salz, Helen K

2011-08-01

The gene regulatory networks that control sex determination vary between species. Despite these differences, comparative studies in insects have found that alternative splicing is reiteratively used in evolution to control expression of the key sex-determining genes. Sex determination is best understood in Drosophila where activation of the RNA binding protein-encoding gene Sex-lethal is the central female-determining event. Sex-lethal serves as a genetic switch because once activated it controls its own expression by a positive feedback splicing mechanism. Sex fate choice in is also maintained by self-sustaining positive feedback splicing mechanisms in other dipteran and hymenopteran insects, although different RNA binding protein-encoding genes function as the binary switch. Studies exploring the mechanisms of sex-specific splicing have revealed the extent to which sex determination is integrated with other developmental regulatory networks. Copyright © 2011 Elsevier Ltd. All rights reserved.

Knowledge, attitudes, and practices among health care providers regarding complementary and alternative medicine in Trinidad and Tobago.

PubMed

Bahall, Mandreker; Legall, George

2017-03-08

Health care providers are often ill prepared to interact about or make acceptable conclusions on complementary and alternative medicine (CAM) despite its widespread use. We explored the knowledge, attitudes, and practices of health care providers regarding CAM. This cross-sectional study was conducted between March 1 and July 31, 2015 among health care providers working mainly in the public sector in Trinidad and Tobago. A 34-item questionnaire was distributed and used for data collection. Questionnaire data were analysed using inferential and binary logistic regression models. Response rate was 60.3% (362/600). Responders were 172 nurses, 77 doctors, 30 pharmacists, and 83 other health care providers of unnamed categories (mainly nursing assistants). Responders were predominantly female (69.1%), Indo-Trinidadian (55.8%), Christian (47.5%), self-claimed "very religious" (48.3%), and had <5 years of working experience (40.6%). The prevalence of CAM use was 92.4% for nurses, 64.9% for doctors, 83.3% for pharmacists, and 77.1% for other health care providers. The majority (50-75%) reported fair knowledge of herbal, spiritual, alternative, and physical types of CAM, but had no knowledge of energy therapy and therapeutic methods. Sex, ethnicity, and type of health care provider were associated with both personal use and recommendation for the use of CAM. Predictors of CAM use were sex, religion, and type of health care provider; predictors of recommendation for the use of CAM were sex and type of health care provider. About half of health care providers (51.4%) and doctors (52%) were likely to ask their patients about CAM and <15% were likely to refer patients to a CAM practitioner. However, health care providers expressed interest in being educated on the subject. Doctors (51.9%) and pharmacists (63.3%) said that combination therapy is superior to conventional medicine alone. Less than 10% said conventional medicine should be used alone. Knowledge about CAM is low among health care providers. The majority engages in using CAM but is reluctant to recommend it. Predictors of CAM use were sex, religion, and profession; predictors of recommendation for the use of CAM were sex and profession. Health care providers feel the future lies in integrative medicine.

Conservation of Sex-Linked Markers among Conspecific Populations of a Viviparous Skink, Niveoscincus ocellatus, Exhibiting Genetic and Temperature-Dependent Sex Determination

PubMed Central

Burridge, Christopher P; Ezaz, Tariq; Wapstra, Erik

2018-01-01

Abstract Sex determination systems are exceptionally diverse and have undergone multiple and independent evolutionary transitions among species, particularly reptiles. However, the mechanisms underlying these transitions have not been established. Here, we tested for differences in sex-linked markers in the only known reptile that is polymorphic for sex determination system, the spotted snow skink, Niveoscincus ocellatus, to quantify the genomic differences that have accompanied this transition. In a highland population, sex is determined genetically, whereas in a lowland population, offspring sex ratio is influenced by temperature. We found a similar number of sex-linked loci in each population, including shared loci, with genotypes consistent with male heterogamety (XY). However, population-specific linkage disequilibrium suggests greater differentiation of sex chromosomes in the highland population. Our results suggest that transitions between sex determination systems can be facilitated by subtle genetic differences. PMID:29659810

Polygenic Sex Determination System in Zebrafish

PubMed Central

Liew, Woei Chang; Bartfai, Richard; Lim, Zijie; Sreenivasan, Rajini; Siegfried, Kellee R.; Orban, Laszlo

2012-01-01

Background Despite the popularity of zebrafish as a research model, its sex determination (SD) mechanism is still unknown. Most cytogenetic studies failed to find dimorphic sex chromosomes and no primary sex determining switch has been identified even though the assembly of zebrafish genome sequence is near to completion and a high resolution genetic map is available. Recent publications suggest that environmental factors within the natural range have minimal impact on sex ratios of zebrafish populations. The primary aim of this study is to find out more about how sex is determined in zebrafish. Methodology/Principal Findings Using classical breeding experiments, we found that sex ratios across families were wide ranging (4.8% to 97.3% males). On the other hand, repeated single pair crossings produced broods of very similar sex ratios, indicating that parental genotypes have a role in the sex ratio of the offspring. Variation among family sex ratios was reduced after selection for breeding pairs with predominantly male or female offspring, another indication that zebrafish sex is regulated genetically. Further examinations by a PCR-based “blind assay" and array comparative genomic hybridization both failed to find universal sex-linked differences between the male and female genomes. Together with the ability to increase the sex bias of lines by selective breeding, these data suggest that zebrafish is unlikely to utilize a chromosomal sex determination (CSD) system. Conclusions/Significance Taken together, our study suggests that zebrafish sex is genetically determined with limited, secondary influences from the environment. As we have not found any sign for CSD in the species, we propose that the zebrafish has a polygenic sex determination system. PMID:22506019

Hooded seal Cystophora cristata foraging areas in the Northeast Atlantic Ocean—Investigated using three complementary methods

PubMed Central

Lydersen, Christian; Biuw, Martin; Haug, Tore; Fedak, Mike A.; Kovacs, Kit M.

2017-01-01

Identifying environmental characteristics that define the ecological niche of a species is essential to understanding how changes in physical conditions might affect its distribution and other aspects of its ecology. The present study used satellite relay data loggers (SRDLs) to study habitat use by Northeast Atlantic hooded seals (N = 20; 9 adult females, 3 adult males, and 8 juveniles). Three different methods were used in combination to achieve maximum insight regarding key foraging areas for hooded seals in this region, which have decline by 85% in recent decades: 1) first passage time (FPT); 2) vertical transit rate and; 3) change in dive drift rate. Generalized additive mixed models (GAMM) were applied to each method to determine whether specific habitat characteristics were associated with foraging. Separate models were run for the post-molting and the post-breeding seasons; sex and age classes were included in the GAMMs. All three methods highlighted a few common geographic areas as being important foraging zones; however, there were also some different areas identified by the different methods, which highlights the importance of using multiple indexes when analyzing tracking and diving data to study foraging behavior. Foraging occurred most commonly in relatively shallow areas with high Sea Surface Temperatures (SST), corresponding to continental shelf areas with Atlantic Water masses. All age and sex classes overlapped spatially to some extent, but the different age and sex groups showed differences in the bathymetry of their foraging areas as well as in their vertical use of the water column. When foraging, pups dove in the upper part of the water column in relatively deep areas. Adult females foraged relatively shallowly in deep water areas too, though in shallower areas than pups. Adult males foraged close to the bottom in shallower areas. PMID:29211797

The interactive association of dietary diversity scores and breast-feeding status with weight and length in Filipino infants aged 6–24 months

PubMed Central

Wright, Melecia J; Bentley, Margaret E; Mendez, Michelle A; Adair, Linda S

2016-01-01

Objective To assess how breast-feeding and dietary diversity relate to infant length-for-age Z-score (LAZ) and weight-for-age Z-score (WAZ). Design Breast-feeding, dietary and anthropometric data from the Cebu Longitudinal Health and Nutrition Survey were analysed using sex-stratified fixed-effects longitudinal regression models. A dietary diversity score (DDS) based on seven food groups was classified as low (<4) or high (≥4). The complementary feeding patterns were: (i) non-breast-fed with low DDS (referent); (ii) breast-fed with low DDS; (iii) non-breast-fed with high DDS; and (iv) breast-fed with high DDS (optimal). Interactions between age, energy intake and complementary feeding patterns were included. Setting Philippines. Subjects Infants (n 2822) measured bimonthly from 6 to 24 months. Results Breast-feeding (regardless of DDS) was significantly associated with higher LAZ (until 24 months) and WAZ (until 20 months). For example, at 6 months, breast-fed boys with low DDS were 0·246 (95 % CI 0·191, 0·302) SD longer and 0·523 (95 % CI 0·451, 0·594) SD heavier than the referent group. There was no significant difference in size between breast-fed infants with high v. low DDS. Similarly, high DDS conferred no advantage in LAZ or WAZ among non-breast- fed infants. There were modest correlations between the 7-point DDS and nutrient intakes but these correlations were substantially attenuated after energy adjustment. We elucidated several interactions between sex, age, energy intake and complementary feeding patterns. Conclusions These results demonstrate the importance of prolonged breast-feeding up to 24 months. The DDS provided qualitative information on infant diets but did not confer a significant advantage in LAZ or WAZ. PMID:25728248

Complementary and alternative medicine use in children with thalassaemia.

PubMed

Efe, Emine; Işler, Ayşegül; Sarvan, Süreyya; Başer, Hayriye; Yeşilipek, Akif

2013-03-01

The aims of this study were to: (1) determine the types of complementary and alternative medicine use among children with thalassaemia as reported by parents and (2) describe sociodemographic and medical factors associated with the use of such treatments in families residing in southern Turkey. Thalassaemia is one of the most common human genetic diseases. Despite the therapeutic efforts, patients will encounter a variety of physical and psychological problems. Therefore, the use of complementary and alternative medicines among children thalassaemia is becoming increasingly popular. This is a descriptive study of complementary and alternative medicine. This study was conducted in the Hematology Outpatient Clinic at Akdeniz University Hospital and in the Thalassemia Centre at Ministry of Health Antalya Education and Research Hospital, Antalya, Turkey, between January 2010-December 2010. Parents of 97 paediatric patients, among 125 parents who applied to the haematology outpatient clinic and thalassaemia centre between these dates, agreed to take part in the study with whom contact could be made were included. Data were collected by using a questionnaire. The proportion of parents who reported using one or more of the complementary and alternative medicine methods was 82·5%. Of these parents, 61·8% were using prayer/spiritual practice, 47·4% were using nutritional supplements and 35·1% were using animal materials. It was determined that a significant portion of the parents using complementary and alternative medicine use it to treat their children's health problems, they were informed about complementary and alternative medicine by their paediatricians and family elders, and they have discussed the use of complementary and alternative medicine with healthcare professionals. To sustain medical treatment and prognosis of thalassaemia, it is important for nurses to consult with their patients and parents regarding the use and potential risks of some complementary and alternative medicine. © 2012 Blackwell Publishing Ltd.

Does the mechanism of sex determination constrain the potential for sex manipulation? A test in geckos with contrasting sex-determining systems

NASA Astrophysics Data System (ADS)

Kratochvíl, Lukáš; Kubička, Lukáš; Landová, Eva

2008-03-01

The concentration of yolk steroids was suggested to influence offspring gender in oviparous animals subject to both temperature-dependent sex determination (TSD) and genotypic sex determination (GSD). However, the proposed mechanisms of steroid effects are thought to differ between TSD and GSD: a direct effect of oestrogens on gonad feminisation in TSD species vs a differential induction of male-producing or female-producing gametes in GSD species. Geckos offer an ideal opportunity for testing these suggested mechanisms. Closely related gecko species differ in their modes of sex determination. They lay clutches of two synchronously formed eggs; both eggs share equal steroid levels. If identical hormonal composition and environment during vitellogenesis, gravidity and incubation determine the sex of the progeny, siblings should share the same gender in both TSD and GSD geckos. We found strong support for this prediction in a TSD gecko species. Among clutches that were incubated at the temperature that produced both sexes, there were no clutches with siblings of the opposite sex. On the other hand, about half of the clutches yielded siblings of the opposite sex in four GSD species. These results suggest that sex-determining systems constrain the ability of the female to produce single-sex siblings and, hence, it seems that the GSD mechanism constrains the opportunities for sex ratio manipulation in geckos via yolk steroid manipulation.

Are Commercial Complementary Food Distributions to Refugees and Migrants in Europe Conforming to International Policies and Guidelines on Infant and Young Child Feeding in Emergencies?

PubMed

Theurich, Melissa Ann; Grote, Veit

2017-08-01

In 2015, more than one million migrants and refugees arrived in Europe. Commercial complementary foods, processed foods marketed for infants and young children 6-23 months of age, were distributed by various humanitarian actors along migrant routes and in European refugee camps. Unsolicited donations and distributions of commercial complementary food products were problematic and divergent from international policies on infant and young child feeding during humanitarian emergencies. Interim guidance regarding commercial complementary foods was published during the peak of the emergency but implemented differently by various humanitarian actors. Clearer and more technical specifications on commercial complementary foods are needed in order to objectively determine their suitability for operational contexts in Europe and emergency nutrition assistance in the future.

Association of Frontline Worker-Provided Services with Change in Block-Level Complementary Feeding Indicators: An Ecological Analysis from Bihar, India

PubMed Central

Das, Aritra; Mahapatra, Sanchita; Sai Mala, Guntur; Chaudhuri, Indrajit; Mahapatra, Tanmay

2016-01-01

Background Insufficiencies in complementary feeding put infants and young children at increased risk of undernutrition. Till now, most Indian studies have looked at the individual level determinants of complementary feeding practices. We aimed to evaluate the association of frontline worker (FLW) provided nutritional counselling services, with change in community level indicators of complementary feeding practices among 9–11 month old children over time. Methods The study data was obtained from five rounds of ‘Lot Quality Assurance Sampling’ survey in eight districts of Bihar, an impoverished Indian state. The surveys were conducted as evaluation exercises for the ‘Integrated Family Health Initiative (IFHI)’–a multi-faceted program aimed at improving the maternal and child health outcomes in Bihar. The main outcome indicators were—current breastfeeding, age-appropriate minimum frequency of semi-solid food, age-appropriate minimum quantity of semi-solid food, initiation of complementary feeding at the right age, and dietary diversity. Repeated measures analysis was performed to determine the association of changes in the outcome indicators with coverage of FLW-provided counselling services. Results Visits by FLW, advices on age-appropriate frequency and handwashing were significant predictors of receiving age-appropriate frequency of feeding. The determinants of receiving age-appropriate quantity were—advices on age appropriate frequency and advices on handwashing. Receiving food support from AWC and FLW visits were significantly associated with initiating complementary feeding at the right age. Conclusions The present study identified the critical elements among the different types of FLW-provided services. The study findings, from an economically and socially underdeveloped region of India, would inform the relevant programs about the nutritional counselling services that need to be emphasized upon for reducing the burden of childhood malnutrition. PMID:27832211

[Health care use by free complementary health insurance coverage beneficiaries in France in 2012].

PubMed

Tuppin, P; Samson, S; Colinot, N; Gastaldi-Menager, C; Fagot-Campagna, A; Gissot, C

2016-04-01

The objective was to investigate healthcare use among people covered by one of the two complementary healthcare insurance schemes available for people with low annual income: CMUC (universal complementary healthcare insurance) and, for people whose income exceeds the CMUC ceiling, ACS (aid for complementary healthcare insurance). Comparisons were made between CMUC and ACS beneficiaries versus CMUC and ACS non-beneficiaries and between CMUC beneficiaries and ACS beneficiaries. Using the national health insurance information system (SNIIRAM), people less than 60 years old covered by the general national health insurance (86% of the 66 million inhabitants) and with ACS or CMUC coverage in 2012 were selected. Diseases were identified using hospital diagnosis, drugs refunds and long-term chronic disease status. Hospital related diagnoses were categorized in major hospital activity groups. Sex- and age-standardized relative risk (RR) were calculated. There were 4.4 million (9.6%) CMUC beneficiaries and 732,000 (1.6%) ACS beneficiaries (56% and 54% women; mean age: 24 years and 29 years respectively versus 52% and 30 years for CMUC or ACS non-beneficiaries). CMUC or ACS beneficiaries had more often cardiovascular diseases (RR=1.4;2.1) and diabetes (RR=2.2;2.4). Their sex- and age-standardized hospitalisation rates for all diagnosis were higher (18%; 17%, RR=1.3;1.4) than CMUC or ACS non-beneficiaries (13%). This was especially the case for the following major groups: toxicology, intoxications, alcohol major group (RR=3.8;4.0); psychiatry (RR=2.8;4.1); respiratory disease (RR=1.9;2.3); infectious disease (RR=1.9;2.7). Compared with CMUC beneficiaries, ACS beneficiaries had more often cancer (RR=1.5), cardiovascular disease (RR=1.5), neurological disease (RR=2.7), psychiatric illness (RR=2.6), end-stage renal disease (RR=2.8), hemophilia (RR=1.4) or cystic fibrosis (RR=1.6) and they received also more often disability allowance (20%, 4%). The disease and hospitalisation rates of ACS beneficiaries are similar or higher than those of CMUC beneficiaries, especially for disabling diseases. Both CMUC and ACS beneficiaries received healthcare for chronic diseases that can be targeted by prevention and screening programs for more optimal healthcare. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Cell-autonomous sex determination outside of the gonad

PubMed Central

Arnold, Arthur P.; Chen, Xuqi; Link, Jenny C.; Itoh, Yuichiro; Reue, Karen

2013-01-01

The classic model of sex determination in mammals states that the sex of the individual is determined by the type of gonad that develops, which in turn determines the gonadal hormonal milieu that creates sex differences outside of the gonads. However, XX and XY cells are intrinsically different because of the cell-autonomous sex-biasing action of X and Y genes. Recent studies of mice, in which sex chromosome complement is independent of gonadal sex, reveal that sex chromosome complement has strong effects contributing to sex differences in phenotypes such as metabolism. Adult mice with two X chromosomes (relative to mice with one X chromosome) show dramatically greater increases in body weight and adiposity after gonadectomy, irrespective of their gonadal sex. When fed a high fat diet, XX mice develop striking hyperinsulinemia and fatty liver, relative to XY mice. The sex chromosome effects are modulated by the presence of gonadal hormones, indicating an interaction of the sex-biasing effects of gonadal hormones and sex chromosome genes. Other cell-autonomous sex chromosome effects are detected in mice in many phenotypes. Birds (relative to eutherian mammals) are expected to show more widespread cell-autonomous sex determination in non-gonadal tissues, because of ineffective sex chromosome dosage compensation mechanisms. PMID:23361913

The impact of chimerism in DNA-based forensic sex determination analysis.

PubMed

George, Renjith; Donald, Preethy Mary; Nagraj, Sumanth Kumbargere; Idiculla, Jose Joy; Hj Ismail, Rashid

2013-01-01

Sex determination is the most important step in personal identification in forensic investigations. DNA-based sex determination analysis is comparatively more reliable than the other conventional methods of sex determination analysis. Advanced technology like real-time polymerase chain reaction (PCR) offers accurate and reproducible results and is at the level of legal acceptance. But still there are situations like chimerism where an individual possess both male and female specific factors together in their body. Sex determination analysis in such cases can give erroneous results. This paper discusses the phenomenon of chimerism and its impact on sex determination analysis in forensic investigations.

Determining the Attitudes and Use of Complementary, Alternative, and Integrative Medicine Among Undergraduates

PubMed Central

Huynh, Ngoc-Tram; Broukhim, Michael; Cheung, Douglas H.; Schuster, Tonya L.; Najm, Wadie

2014-01-01

Abstract Objectives: To (1) determine the attitudes, perceptions, and use of complementary, alternative, and integrative medicine among undergraduate students; (2) assess whether these students would benefit from more academic exposure to complementary and alternative medicine (CAM) and promotion of integrative medicine (IM); and (3) gauge the need and desire of undergraduates, particularly pre-health learners, to take courses about CAM/IM. Methods: This cross-sectional electronic survey study was conducted on the campus of the University of California (UC) Irvine. Selection criteria included being at least 18 years of age and a current undergraduate at UC Irvine. All survey responses were collected between November 20, 2010, and June 1, 2011. The data were analyzed by using Stata software, version 11-SE (Stata Corp., College Station, TX). Results: Completed surveys were received from 2839 participants (mean age of respondents, 20.2 years). Thirty-five percent had used CAM within the past 12 months, and 92.8% believed CAM to be at least somewhat effective; however, only 31% had prior education on CAM. After adjustment for variables, familiarity and belief in effectiveness were both highly linked to the use of CAM, with ascending odds ratios (ORs; 95% confidence interval [CI]) of 3.9 (3.1–4.9), 8.1 (5.7–11.5), 13.4 (6.0–30.2), 2.1 (1.3–3.4), 4.9 (3.0–7.8), and 12.7 (6.9–23.4) among increasing categories (all p<0.01). Sex (OR, 1.26 [95% CI, 1.01–1.56]; p<0.05), Asian ethnicity (1.46 [1.14–1.88]; p<0.01), and prior education (1.26 [1.01–1.57]; p<0.05) were also significantly correlated to the use of CAM after adjustment. Most respondents indicated that they were likely to take a CAM college course if it fulfilled a graduation requirement (63.6%) or was offered within their major (56.4%). Conclusions: Overall, this large-scale study supports the ideas that education plays a pivotal factor in the decision to use CAM and that there is a large demand for additional CAM knowledge among college students. PMID:24992360

To whom is HIV pre-exposure prophylaxis proposed?

PubMed

Ayerdi-Aguirrebengoa, Oskar; Vera-García, Mar; Puerta-López, Teresa; Raposo-Utrilla, Montserrat; Rodríguez-Martín, Carmen; Del Romero-Guerrero, Jorge

2017-05-01

HIV Pre-Exposure Prophylaxis (PrEP) consists of administering antiretroviral drugs to seronegative individuals with high risk practices. The aim of the study was to describe the characteristics of recent seroconverted HIV patients in order to determine the profile of the appropriate candidates for PrEP. A descriptive study of all patients diagnosed with HIV infection in 2014, and who had achieved a documented negative serology over the previous 12 months. A specific form was completed to determine the sociodemographic, behavioural, and clinical features, with complementary tests being performed for other sexually transmitted infections. Almost all (98.4%) of the 61 recent seroconverted were men who have sex with men, and aged between 20 to 39 years (88.5%). They also had a background of sexually transmitted infections (80.3%), performed multiple and unprotected sexual practices (82.7%), and under the effect of recreational drugs (87%). The evaluation of the risk factors for HIV infection in seronegative patients should enable the appropriate candidates for PrEP to be identified. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

The Y Chromosome

ERIC Educational Resources Information Center

Offner, Susan

2010-01-01

The Y chromosome is of great interest to students and can be used to teach about many important biological concepts in addition to sex determination. This paper discusses mutation, recombination, mammalian sex determination, sex determination in general, and the evolution of sex determination in mammals. It includes a student activity that…

Random sex determination: When developmental noise tips the sex balance.

PubMed

Perrin, Nicolas

2016-12-01

Sex-determining factors are usually assumed to be either genetic or environmental. The present paper aims at drawing attention to the potential contribution of developmental noise, an important but often-neglected component of phenotypic variance. Mutual inhibitions between male and female pathways make sex a bistable equilibrium, such that random fluctuations in the expression of genes at the top of the cascade are sufficient to drive individual development toward one or the other stable state. Evolutionary modeling shows that stochastic sex determinants should resist elimination by genetic or environmental sex determinants under ecologically meaningful settings. On the empirical side, many sex-determination systems traditionally considered as environmental or polygenic actually provide evidence for large components of stochasticity. In reviewing the field, I argue that sex-determination systems should be considered within a three-ends continuum, rather than the classical two-ends continuum. © 2016 WILEY Periodicals, Inc.

Vertebrate sex-determining genes play musical chairs

PubMed Central

Pan, Qiaowei; Anderson, Jennifer; Bertho, Sylvain; Herpin, Amaury; Wilson, Catherine; Postlethwait, John H.; Schartl, Manfred; Guiguen, Yann

2017-01-01

Sexual reproduction is one of the most highly conserved processes in evolution. However, the genetic and cellular mechanisms making the decision of whether the undifferentiated gonad of animal embryos develops either towards male or female are manifold and quite diverse. In vertebrates, sex-determining mechanisms range from environmental to simple or complex genetic mechanisms and different mechanisms have evolved repeatedly and independently. In species with simple genetic sex-determination, master sex-determining genes lying on sex chromosomes drive the gonadal differentiation process by switching on a developmental program, which ultimately leads to testicular or ovarian differentiation. So far, very few sex-determining genes have been identified in vertebrates and apart from mammals and birds, these genes are apparently not conserved over a larger number of related orders, families, genera, or even species. To fill this knowledge gap and to better explore genetic sex-determination, we propose a strategy (RAD-Sex) that makes use of next-generation sequencing technology to identify genetic markers that define sex-specific segments of the male or female genome. PMID:27291506

Sex Reversal in Reptiles: Reproductive Oddity or Powerful Driver of Evolutionary Change?

PubMed

Holleley, Clare E; Sarre, Stephen D; O'Meally, Denis; Georges, Arthur

2016-01-01

Is sex a product of genes, the environment, or both? In this review, we describe the diversity of sex-determining mechanisms in reptiles, with a focus on systems that display gene-environment interactions. We summarise the field and laboratory-based evidence for the occurrence of environmental sex reversal in reptiles and ask whether this is a widespread evolutionary mechanism affecting the evolution of sex chromosomes and speciation in vertebrates. Sex determination systems exist across a continuum of genetic and environmental influences, blurring the lines between what was once considered a strict dichotomy between genetic sex determination and temperature-dependent sex determination. Across this spectrum, we identify the potential for sex reversal in species with clearly differentiated heteromorphic sex chromosomes (Pogona vitticeps, Bassiana duperreyi, Eremias multiocellata, Gekko japonicus), weakly differentiated homomorphic sex chromosomes (Niveoscincus ocellatus), and species with only a weak heritable predisposition for sex (Emys orbicularis, Trachemys scripta). We argue that sex reversal is widespread in reptiles (Testudines, Lacertidae, Agamidae, Scincidae, Gekkonidae) and has the potential to have an impact on individual fitness, resulting in reproductively, morphologically, and behaviourally unique phenotypes. Sex reversal is likely to be a powerful evolutionary force responsible for generating and maintaining lability and diversity in reptile sex-determining modes. © 2016 S. Karger AG, Basel.

Length and weight of very low birth weight infants in Germany at 2 years of age: does it matter at what age they start complementary food?

PubMed

Spiegler, J; Eisemann, N; Ehlers, S; Orlikowsky, T; Kannt, O; Herting, E; Göpel, W

2015-06-01

We analysed at what age parents start complementary food in very low birth weight infants, determined risk factors for early introduction of complementary food (post-term age) and analysed whether the age at introduction of complementary food influences height or weight at 2 years of age. Parents of premature infants born in 2009-2011 answered questionnaires regarding introduction of complementary food in the first year of life (N=2262) and were followed up at a post-term age of 2 years (N=981). Length and weight were compared with full-term infants from the KiGGs study. Logistic and linear regression analyses were conducted to study predictors for early introduction of complementary food and the influence of age at introduction of complementary food on later height and weight. Average age at introduction of complementary food was 3.5 months post-term age. The lower the gestational age at birth, the earlier (post-term age) vegetables and meat were introduced. Age at introduction of complementary food was influenced by intrauterine growth restriction, gestational age at birth, maternal education and a developmental delay perceived by the parents. Length and weight at a post-term age of 2 years was not negatively influenced by early introduction of complementary food. VLBW infants are introduced to complementary food on average before a post-term age of 4 months. There was no negative effect of early introduction of complementary food on height and weight at 2 years of age.

Multiple Sex-Associated Regions and a Putative Sex Chromosome in Zebrafish Revealed by RAD Mapping and Population Genomics

PubMed Central

Anderson, Jennifer L.; Rodríguez Marí, Adriana; Braasch, Ingo; Amores, Angel; Hohenlohe, Paul; Batzel, Peter; Postlethwait, John H.

2012-01-01

Within vertebrates, major sex determining genes can differ among taxa and even within species. In zebrafish (Danio rerio), neither heteromorphic sex chromosomes nor single sex determination genes of large effect, like Sry in mammals, have yet been identified. Furthermore, environmental factors can influence zebrafish sex determination. Although progress has been made in understanding zebrafish gonad differentiation (e.g. the influence of germ cells on gonad fate), the primary genetic basis of zebrafish sex determination remains poorly understood. To identify genetic loci associated with sex, we analyzed F2 offspring of reciprocal crosses between Oregon *AB and Nadia (NA) wild-type zebrafish stocks. Genome-wide linkage analysis, using more than 5,000 sequence-based polymorphic restriction site associated (RAD-tag) markers and population genomic analysis of more than 30,000 single nucleotide polymorphisms in our *ABxNA crosses revealed a sex-associated locus on the end of the long arm of chr-4 for both cross families, and an additional locus in the middle of chr-3 in one cross family. Additional sequencing showed that two SNPs in dmrt1 previously suggested to be functional candidates for sex determination in a cross of ABxIndia wild-type zebrafish, are not associated with sex in our AB fish. Our data show that sex determination in zebrafish is polygenic and that different genes may influence sex determination in different strains or that different genes become more important under different environmental conditions. The association of the end of chr-4 with sex is remarkable because, unique in the karyotype, this chromosome arm shares features with known sex chromosomes: it is highly heterochromatic, repetitive, late replicating, and has reduced recombination. Our results reveal that chr-4 has functional and structural properties expected of a sex chromosome. PMID:22792396

Genetic Disorders

MedlinePlus

... from the baby’s father. What determines my baby’s sex? Your baby’s sex is determined by sex chromosomes. ... be a carrier of the disorder. What are sex-linked disorders? Sex-linked disorders are caused by ...

Did Lizards Follow Unique Pathways in Sex Chromosome Evolution?

PubMed Central

Gleeson, Dianne; Georges, Arthur

2018-01-01

Reptiles show remarkable diversity in modes of reproduction and sex determination, including high variation in the morphology of sex chromosomes, ranging from homomorphic to highly heteromorphic. Additionally, the co-existence of genotypic sex determination (GSD) and temperature-dependent sex determination (TSD) within and among sister clades makes this group an attractive model to study and understand the evolution of sex chromosomes. This is particularly so with Lizards (Order Squamata) which, among reptiles, show extraordinary morphological diversity. They also show no particular pattern of sex chromosome degeneration of the kind observed in mammals, birds and or even in snakes. We therefore speculate that sex determination sensu sex chromosome evolution is labile and rapid and largely follows independent trajectories within lizards. Here, we review the current knowledge on the evolution of sex chromosomes in lizards and discuss how sex chromosome evolution within that group differs from other amniote taxa, facilitating unique evolutionary pathways. PMID:29751579

Evidence of oligogenic sex determination in the apple snail Pomacea canaliculata.

PubMed

Yusa, Yoichi; Kumagai, Natsumi

2018-06-01

A small number of genes may interact to determine sex, but few such examples have been demonstrated in animals, especially through comprehensive mating experiments. The highly invasive apple snail Pomacea canaliculata is gonochoristic and shows a large variation in brood sex ratio, and the involvement of multiple genes has been suggested for this phenomenon. We conducted mating experiments to determine whether their sex determination involves a few or many genes (i.e., oligogenic or polygenic sex determination, respectively). Full-sib females or males that were born from the same parents were mated to an adult of the opposite sex, and the brood sex ratios of the parents and their offspring were investigated. Analysis of a total of 4288 offspring showed that the sex ratios of offspring from the full-sib females were variable but clustered into only a few values. Similar patterns were observed for the full-sib males, although the effect was less clear because fewer offspring were used (n = 747). Notably, the offspring sex ratios of all full-sib females in some families were nearly 0.5 (proportion of males) with little variation. These results indicate that the number of genotypes of the full-sibs, and hence genes involved in sex determination, is small in this snail. Such oligogenic systems may be a major sex-determining system among animals, especially those with variable sex ratios.

Evolutionary diversity and turn-over of sex determination in teleost fishes.

PubMed

Mank, J E; Avise, J C

2009-01-01

Sex determination, due to the obvious association with reproduction and Darwinian fitness, has been traditionally assumed to be a relatively conserved trait. However, research on teleost fishes has shown that this need not be the case, as these animals display a remarkable diversity in the ways that they determine sex. These different mechanisms, which include constitutive genetic mechanisms on sex chromosomes, polygenic constitutive mechanisms, environmental influences, hermaphroditism, and unisexuality have each originated numerous independent times in the teleosts. The evolutionary lability of sex determination, and the corresponding rapid rate of turn-over among different modes, makes the teleost clade an excellent model with which to test theories regarding the evolution of sex determining adaptations. Much of the plasticity in sex determination likely results from the dynamic teleost genome, and recent advances in fish genetics and genomics have revealed the role of gene and genome duplication in fostering emergence and turn-over of sex determining mechanisms. 2009 S. Karger AG, Basel.

Differential intron retention in Jumonji chromatin modifier genes is implicated in reptile temperature-dependent sex determination

PubMed Central

Deveson, Ira W.; Holleley, Clare E.; Blackburn, James; Marshall Graves, Jennifer A.; Mattick, John S.; Waters, Paul D.; Georges, Arthur

2017-01-01

In many vertebrates, sex of offspring is determined by external environmental cues rather than by sex chromosomes. In reptiles, for instance, temperature-dependent sex determination (TSD) is common. Despite decades of work, the mechanism by which temperature is converted into a sex-determining signal remains mysterious. This is partly because it is difficult to distinguish the primary molecular events of TSD from the confounding downstream signatures of sexual differentiation. We use the Australian central bearded dragon, in which chromosomal sex determination is overridden at high temperatures to produce sex-reversed female offspring, as a unique model to identify TSD-specific features of the transcriptome. We show that an intron is retained in mature transcripts from each of two Jumonji family genes, JARID2 and JMJD3, in female dragons that have been sex-reversed by temperature but not in normal chromosomal females or males. JARID2 is a component of the master chromatin modifier Polycomb Repressive Complex 2, and the mammalian sex-determining factor SRY is directly regulated by an independent but closely related Jumonji family member. We propose that the perturbation of JARID2/JMJD3 function by intron retention alters the epigenetic landscape to override chromosomal sex-determining cues, triggering sex reversal at extreme temperatures. Sex reversal may then facilitate a transition from genetic sex determination to TSD, with JARID2/JMJD3 intron retention preserved as the decisive regulatory signal. Significantly, we also observe sex-associated differential retention of the equivalent introns in JARID2/JMJD3 transcripts expressed in embryonic gonads from TSD alligators and turtles, indicative of a reptile-wide mechanism controlling TSD. PMID:28630932

Differential intron retention in Jumonji chromatin modifier genes is implicated in reptile temperature-dependent sex determination.

PubMed

Deveson, Ira W; Holleley, Clare E; Blackburn, James; Marshall Graves, Jennifer A; Mattick, John S; Waters, Paul D; Georges, Arthur

2017-06-01

In many vertebrates, sex of offspring is determined by external environmental cues rather than by sex chromosomes. In reptiles, for instance, temperature-dependent sex determination (TSD) is common. Despite decades of work, the mechanism by which temperature is converted into a sex-determining signal remains mysterious. This is partly because it is difficult to distinguish the primary molecular events of TSD from the confounding downstream signatures of sexual differentiation. We use the Australian central bearded dragon, in which chromosomal sex determination is overridden at high temperatures to produce sex-reversed female offspring, as a unique model to identify TSD-specific features of the transcriptome. We show that an intron is retained in mature transcripts from each of two Jumonji family genes, JARID2 and JMJD3 , in female dragons that have been sex-reversed by temperature but not in normal chromosomal females or males. JARID2 is a component of the master chromatin modifier Polycomb Repressive Complex 2, and the mammalian sex-determining factor SRY is directly regulated by an independent but closely related Jumonji family member. We propose that the perturbation of JARID2/JMJD3 function by intron retention alters the epigenetic landscape to override chromosomal sex-determining cues, triggering sex reversal at extreme temperatures. Sex reversal may then facilitate a transition from genetic sex determination to TSD, with JARID2/JMJD3 intron retention preserved as the decisive regulatory signal. Significantly, we also observe sex-associated differential retention of the equivalent introns in JARID2/JMJD3 transcripts expressed in embryonic gonads from TSD alligators and turtles, indicative of a reptile-wide mechanism controlling TSD.

Plant Sex Determination.

PubMed

Pannell, John R

2017-03-06

Sex determination is as important for the fitness of plants as it is for animals, but its mechanisms appear to vary much more among plants than among animals, and the expression of gender in plants differs in important respects from that in most animals. In this Minireview, I provide an overview of the broad variety of ways in which plants determine sex. I suggest that several important peculiarities of plant sex determination can be understood by recognising that: plants show an alternation of generations between sporophytic and gametophytic phases (either of which may take control of sex determination); plants are modular in structure and lack a germ line (allowing for a quantitative expression of gender that is not common in animals); and separate sexes in plants have ultimately evolved from hermaphroditic ancestors. Most theorising about sex determination in plants has focused on dioecious species, but we have much to learn from monecious or hermaphroditic species, where sex is determined at the level of modules, tissues or cells. Because of the fundamental modularity of plant development and potentially important evolutionary links between monoecy and dioecy, it may be useful to relax the distinction often made between 'developmental sex determination' (which underpins the development of male versus female flowers in monoecious species) and 'genetic sex determination' (which underpins the separation of males and females in dioecious species, often mediated by a genetic polymorphism and sex chromosomes). I also argue for relaxing the distinction between sex determination involving a genetic polymorphism and that involving responses to environmental or hormonal cues, because non-genetic cues might easily be converted into genetic switches. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular and Cellular Sex Differences at the Intersection of Stress and Arousal

PubMed Central

Valentino, Rita J.; Reyes, Beverly; Van Bockstaele, Elisabeth; Bangasser, Debra

2011-01-01

Elucidating the mechanisms underlying sex biases in the prevalence and severity of diseases can advance our understanding of their pathophysiological basis and serve as a guide for developing treatments. A well-established sex difference in psychiatry is the higher incidence of mood and anxiety disorders in females. These disorders share stress as a potential etiological contributor and hyperarousal as a core symptom, suggesting that the distinction between sexes lies at the intersection of stress and arousal systems. This review focuses on the link between the stress axis and the brain norepinephrine arousal system as a key point at which sex differences occur and are translated to differences in the expression of mood disorders. Evidence for a circuit designed to relay emotion-related information via the limbic corticotropin-releasing factor (CRF) system to the locus coeruleus (LC)–norepinephrine arousal system is reviewed. This is followed by recent novel findings of sex differences in CRF receptor signaling and trafficking that would result in an enhanced arousal response and a compromised ability to adapt to chronic stress in females. Finally, we discuss evidence for sex differences in LC dendritic structure that allow for increased receipt and processing of limbic information in females compared to males. Together these complementary sets of data suggest that in females, the LC arousal system is poised to process more limbic information and to respond to some of this information in an enhanced manner compared to males. The clinical and therapeutic considerations arising from this perspective are discussed. PMID:21712048

Sex determination and maintenance: the role of DMRT1 and FOXL2

PubMed Central

Huang, Shengsong; Ye, Leping; Chen, Haolin

2017-01-01

In many species, including mammals, sex determination is genetically based. The sex chromosomes that individuals carry determine sex identity. Although the genetic base of phenotypic sex is determined at the moment of fertilization, the development of testes or ovaries in the bipotential early gonads takes place during embryogenesis. During development, sex determination depends upon very few critical genes. When one of these key genes functions inappropriately, sex reversal may happen. Consequently, an individual's sex phenotype may not necessarily be consistent with the sex chromosomes that are present. For some time, it has been assumed that once the fetal choice is made between male and female in mammals, the gonadal sex identity of an individual remains stable. However, recent studies in mice have provided evidence that it is possible for the gonadal sex phenotype to be switched even in adulthood. These studies have shown that two key genes, doublesex and mad-3 related transcription factor 1 (Dmrt1) and forkhead box L2 (Foxl2), function in a Yin and Yang relationship to maintain the fates of testes or ovaries in adult mammals, and that mutations in either gene might have a dramatic effect on gonadal phenotype. Thus, adult gonad maintenance in addition to fetal sex determination may both be important for the fertility. PMID:28091399

Use of complementary and alternative medicine by pediatric patients with functional and organic gastrointestinal diseases: results from a multicenter survey.

PubMed

Vlieger, Arine M; Blink, Marjolein; Tromp, Ellen; Benninga, Marc A

2008-08-01

Many pediatric patients use complementary and alternative medicine, especially when facing a chronic illness for which treatment options are limited. So far, research on the use of complementary and alternative medicine in patients with functional gastrointestinal disease has been scarce. This study was designed to assess complementary and alternative medicine use in children with different gastrointestinal diseases, including functional disorders, to determine which factors predicted complementary and alternative medicine use and to assess the willingness of parents to participate in future studies on complementary and alternative medicine efficacy and safety. The prevalence of complementary and alternative medicine use was assessed by using a questionnaire for 749 children visiting pediatric gastroenterology clinics of 9 hospitals in the Netherlands. The questionnaire consisted of 35 questions on the child's gastrointestinal disease, medication use, health status, past and future complementary and alternative medicine use, reasons for its use, and the necessity of complementary and alternative medicine research. In this study population, the frequency of complementary and alternative medicine use was 37.6%. A total of 60.3% of this group had used complementary and alternative medicine specifically for their gastrointestinal disease. This specific complementary and alternative medicine use was higher in patients with functional disorders than organic disorders (25.3% vs 17.2%). Adverse effects of allopathic medication, school absenteeism, age

Conflict over condition-dependent sex allocation can lead to mixed sex-determination systems

PubMed Central

Kuijper, Bram; Pen, Ido

2014-01-01

Theory suggests that genetic conflicts drive turnovers between sex-determining mechanisms, yet these studies only apply to cases where sex allocation is independent of environment or condition. Here, we model parent–offspring conflict in the presence of condition-dependent sex allocation, where the environment has sex-specific fitness consequences. Additionally, one sex is assumed to be more costly to produce than the other, which leads offspring to favor a sex ratio less biased toward the cheaper sex in comparison to the sex ratio favored by mothers. The scope for parent–offspring conflict depends on the relative frequency of both environments: when one environment is less common than the other, parent–offspring conflict can be reduced or even entirely absent, despite a biased population sex ratio. The model shows that conflict-driven invasions of condition-independent sex factors (e.g., sex chromosomes) result either in the loss of condition-dependent sex allocation, or, interestingly, lead to stable mixtures of condition-dependent and condition-independent sex factors. The latter outcome corresponds to empirical observations in which sex chromosomes are present in organisms with environment-dependent sex determination. Finally, conflict can also favor errors in environmental perception, potentially resulting in the loss of condition-dependent sex allocation without genetic changes to sex-determining loci. PMID:25180669

Climate-driven shifts in adult sex ratios via sex reversals: the type of sex determination matters.

PubMed

Bókony, Veronika; Kövér, Szilvia; Nemesházi, Edina; Liker, András; Székely, Tamás

2017-09-19

Sex reversals whereby individuals of one genetic sex develop the phenotype of the opposite sex occur in ectothermic vertebrates with genetic sex-determination systems that are sensitive to extreme temperatures during sexual differentiation. Recent rises in global temperatures have led researchers to predict that sex reversals will become more common, resulting in the distortion of many populations' sex ratios. However, it is unclear whether susceptibility to climate-driven sex-ratio shifts depends on the type of sex determination that varies across species. First, we show here using individual-based theoretical models that XX/XY (male-heterogametic) and ZZ/ZW (female-heterogametic) sex-determination systems can respond differentially to temperature-induced sex reversals. Interestingly, the impacts of climate warming on adult sex ratio (ASR) depend on the effects of both genotypic and phenotypic sex on survival and reproduction. Second, we analyse the temporal changes of ASR in natural amphibian populations using data from the literature, and find that ASR shifted towards males in ZZ/ZW species over the past 60 years, but did not change significantly in XX/XY species. Our results highlight the fact that we need a better understanding of the interactions between genetic and environmental sex-determining mechanisms to predict the responses of ectotherms to climate change and the associated extinction risks.This article is part of the themed issue 'Adult sex ratios and reproductive decisions: a critical re-examination of sex differences in human and animal societies'. © 2017 The Author(s).

High-throughput analysis of the satellitome revealed enormous diversity of satellite DNAs in the neo-Y chromosome of the cricket Eneoptera surinamensis.

PubMed

Palacios-Gimenez, Octavio Manuel; Dias, Guilherme Borges; de Lima, Leonardo Gomes; Kuhn, Gustavo Campos E Silva; Ramos, Érica; Martins, Cesar; Cabral-de-Mello, Diogo Cavalcanti

2017-07-25

Satellite DNAs (satDNAs) constitute large portion of eukaryote genomes, comprising non-protein-coding sequences tandemly repeated. They are mostly found in heterochromatic regions of chromosomes such as around centromere or near telomeres, in intercalary heterochromatin, and often in non-recombining segments of sex chromosomes. We examined the satellitome in the cricket Eneoptera surinamensis (2n = 9, neo-X 1 X 2 Y, males) to characterize the molecular evolution of its neo-sex chromosomes. To achieve this, we analyzed illumina reads using graph-based clustering and complementary analyses. We found an unusually high number of 45 families of satDNAs, ranging from 4 bp to 517 bp, accounting for about 14% of the genome and showing different modular structures and high diversity of arrays. FISH mapping revealed that satDNAs are located mostly in C-positive pericentromeric regions of the chromosomes. SatDNAs enrichment was also observed in the neo-sex chromosomes in comparison to autosomes. Especially astonishing accumulation of satDNAs loci was found in the highly differentiated neo-Y, including 39 satDNAs over-represented in this chromosome, which is the greatest satDNAs diversity yet reported for sex chromosomes. Our results suggest possible involvement of satDNAs in genome increasing and in molecular differentiation of the neo-sex chromosomes in this species, contributing to the understanding of sex chromosome composition and evolution in Orthoptera.

Genetic regulation of maize flower development and sex determination.

PubMed

Li, Qinglin; Liu, Baoshen

2017-01-01

The determining process of pistil fate are central to maize sex determination, mainly regulated by a genetic network in which the sex-determining genes SILKLESS 1 , TASSEL SEED 1 , TASSEL SEED 2 and the paramutagenic locus Required to maintain repression 6 play pivotal roles. Maize silks, which emerge from the ear shoot and derived from the pistil, are the functional stigmas of female flowers and play a pivotal role in pollination. Previous studies on sex-related mutants have revealed that sex-determining genes and phytohormones play an important role in the regulation of flower organogenesis. The processes determining pistil fate are central to flower development, where a silk identified gene SILKLESS 1 (SK1) is required to protect pistil primordia from a cell death signal produced by two commonly known genes, TASSEL SEED 1 (TS1) and TASSEL SEED 2 (TS2). In this review, maize flower developmental process is presented together with a focus on important sex-determining mutants and hormonal signaling affecting pistil development. The role of sex-determining genes, microRNAs, phytohormones, and the paramutagenic locus Required to maintain repression 6 (Rmr6), in forming a regulatory network that determines pistil fate, is discussed. Cloning SK1 and clarifying its function were crucial in understanding the regulation network of sex determination. The signaling mechanisms of phytohormones in sex determination are also an important research focus.

Sex determination: why so many ways of doing it?

PubMed

Bachtrog, Doris; Mank, Judith E; Peichel, Catherine L; Kirkpatrick, Mark; Otto, Sarah P; Ashman, Tia-Lynn; Hahn, Matthew W; Kitano, Jun; Mayrose, Itay; Ming, Ray; Perrin, Nicolas; Ross, Laura; Valenzuela, Nicole; Vamosi, Jana C

2014-07-01

Sexual reproduction is an ancient feature of life on earth, and the familiar X and Y chromosomes in humans and other model species have led to the impression that sex determination mechanisms are old and conserved. In fact, males and females are determined by diverse mechanisms that evolve rapidly in many taxa. Yet this diversity in primary sex-determining signals is coupled with conserved molecular pathways that trigger male or female development. Conflicting selection on different parts of the genome and on the two sexes may drive many of these transitions, but few systems with rapid turnover of sex determination mechanisms have been rigorously studied. Here we survey our current understanding of how and why sex determination evolves in animals and plants and identify important gaps in our knowledge that present exciting research opportunities to characterize the evolutionary forces and molecular pathways underlying the evolution of sex determination.

Sex Determination: Why So Many Ways of Doing It?

PubMed Central

Bachtrog, Doris; Mank, Judith E.; Peichel, Catherine L.; Kirkpatrick, Mark; Otto, Sarah P.; Ashman, Tia-Lynn; Hahn, Matthew W.; Kitano, Jun; Mayrose, Itay; Ming, Ray; Perrin, Nicolas; Ross, Laura; Valenzuela, Nicole; Vamosi, Jana C.

2014-01-01

Sexual reproduction is an ancient feature of life on earth, and the familiar X and Y chromosomes in humans and other model species have led to the impression that sex determination mechanisms are old and conserved. In fact, males and females are determined by diverse mechanisms that evolve rapidly in many taxa. Yet this diversity in primary sex-determining signals is coupled with conserved molecular pathways that trigger male or female development. Conflicting selection on different parts of the genome and on the two sexes may drive many of these transitions, but few systems with rapid turnover of sex determination mechanisms have been rigorously studied. Here we survey our current understanding of how and why sex determination evolves in animals and plants and identify important gaps in our knowledge that present exciting research opportunities to characterize the evolutionary forces and molecular pathways underlying the evolution of sex determination. PMID:24983465

Constraints on temperature-dependent sex determination in the leopard gecko ( Eublepharis macularius): response to Kratochvil et al.

NASA Astrophysics Data System (ADS)

Huang, Victoria; Sakata, Jon T.; Rhen, Turk; Coomber, Patricia; Simmonds, Sarah; Crews, David

2008-12-01

Kratochvil et al. (Naturwissenschaften 95:209 215, 2008) reported recently that in the leopard gecko ( Eublepharis macularius) of the family Eublepharidae with temperature-dependent sex determination (TSD), clutches in which eggs were incubated at the same temperature produce only same-sex siblings. Interpreting this result in light of studies of sex steroid hormone involvement in sex determination, they suggested that maternally derived yolk steroid hormones could constrain sex-determining mechanisms in TSD reptiles. We have worked extensively with this species and have routinely incubated clutches at constant temperatures. To test the consistency of high frequency same-sex clutches across different incubation temperatures, we examined our records of clutches at the University of Texas at Austin from 1992 to 2001. We observed that clutches in which eggs were incubated at the same incubation temperature produced mixed-sex clutches as well as same-sex clutches. Furthermore, cases in which eggs within a clutch were separated and incubated at different temperatures produced the expected number of mixed-sex clutches. These results suggest that maternal influences on sex determination are secondary relative to incubation temperature effects.

Wild Sex in Zebrafish: Loss of the Natural Sex Determinant in Domesticated Strains

PubMed Central

Wilson, Catherine A.; High, Samantha K.; McCluskey, Braedan M.; Amores, Angel; Yan, Yi-lin; Titus, Tom A.; Anderson, Jennifer L.; Batzel, Peter; Carvan, Michael J.; Schartl, Manfred; Postlethwait, John H.

2014-01-01

Sex determination can be robustly genetic, strongly environmental, or genetic subject to environmental perturbation. The genetic basis of sex determination is unknown for zebrafish (Danio rerio), a model for development and human health. We used RAD-tag population genomics to identify sex-linked polymorphisms. After verifying this “RAD-sex” method on medaka (Oryzias latipes), we studied two domesticated zebrafish strains (AB and TU), two natural laboratory strains (WIK and EKW), and two recent isolates from nature (NA and CB). All four natural strains had a single sex-linked region at the right tip of chromosome 4, enabling sex genotyping by PCR. Genotypes for the single nucleotide polymorphism (SNP) with the strongest statistical association to sex suggested that wild zebrafish have WZ/ZZ sex chromosomes. In natural strains, “male genotypes” became males and some “female genotypes” also became males, suggesting that the environment or genetic background can cause female-to-male sex reversal. Surprisingly, TU and AB lacked detectable sex-linked loci. Phylogenomics rooted on D. nigrofasciatus verified that all strains are monophyletic. Because AB and TU branched as a monophyletic clade, we could not rule out shared loss of the wild sex locus in a common ancestor despite their independent domestication. Mitochondrial DNA sequences showed that investigated strains represent only one of the three identified zebrafish haplogroups. Results suggest that zebrafish in nature possess a WZ/ZZ sex-determination mechanism with a major determinant lying near the right telomere of chromosome 4 that was modified during domestication. Strains providing the zebrafish reference genome lack key components of the natural sex-determination system but may have evolved variant sex-determining mechanisms during two decades in laboratory culture. PMID:25233988

First Assessment of the Sex Ratio for an East Pacific Green Sea Turtle Foraging Aggregation: Validation and Application of a Testosterone ELISA.

PubMed

Allen, Camryn D; Robbins, Michelle N; Eguchi, Tomoharu; Owens, David W; Meylan, Anne B; Meylan, Peter A; Kellar, Nicholas M; Schwenter, Jeffrey A; Nollens, Hendrik H; LeRoux, Robin A; Dutton, Peter H; Seminoff, Jeffrey A

2015-01-01

Determining sex ratios of endangered populations is important for wildlife management, particularly species subject to sex-specific threats or that exhibit temperature-dependent sex determination. Sea turtle sex is determined by incubation temperature and individuals lack external sex-based traits until sexual maturity. Previous research utilized serum/plasma testosterone radioimmunoassays (RIA) to determine sex in immature/juvenile sea turtles. However, there has been a growing application of enzyme-linked immunosorbent assay (ELISA) for wildlife endocrinology studies, but no study on sea turtles has compared the results of ELISA and RIA. This study provides the first sex ratio for a threatened East Pacific green sea turtle (Chelonia mydas) foraging aggregation, a critical step for future management of this species. Here, we validate a testosterone ELISA and compare results between RIA and ELISA of duplicate samples. The ELISA demonstrated excellent correspondence with the RIA for providing testosterone concentrations for sex determination. Neither assay proved reliable for predicting the sex of reproductively active females with increased testosterone production. We then applied ELISA to examine the sex ratio of 69 green turtles foraging in San Diego Bay, California. Of 45 immature turtles sampled, sex could not be determined for three turtles because testosterone concentrations fell between the ranges for either sex (females: 4.1-113.1 pg/mL, males: 198.4-2,613.0 pg/mL) and these turtles were not subsequently recaptured to enable sex determination; using a Bayesian model to predict probabilities of turtle sex we predicted all three 'unknowns' were female (> 0.86). Additionally, the model assigned all turtles with their correct sex (if determined at recapture) with 100% accuracy. Results indicated a female bias (2.83F:1M) among all turtles in the aggregation; when focusing only on putative immature turtles the sex ratio was 3.5F:1M. With appropriate validation, ELISA sexing could be applied to other sea turtle species, and serve as a crucial conservation tool.

First Assessment of the Sex Ratio for an East Pacific Green Sea Turtle Foraging Aggregation: Validation and Application of a Testosterone ELISA

PubMed Central

Allen, Camryn D.; Robbins, Michelle N.; Eguchi, Tomoharu; Owens, David W.; Meylan, Anne B.; Meylan, Peter A.; Kellar, Nicholas M.; Schwenter, Jeffrey A.; Nollens, Hendrik H.; LeRoux, Robin A.; Dutton, Peter H.; Seminoff, Jeffrey A.

2015-01-01

Determining sex ratios of endangered populations is important for wildlife management, particularly species subject to sex-specific threats or that exhibit temperature-dependent sex determination. Sea turtle sex is determined by incubation temperature and individuals lack external sex-based traits until sexual maturity. Previous research utilized serum/plasma testosterone radioimmunoassays (RIA) to determine sex in immature/juvenile sea turtles. However, there has been a growing application of enzyme-linked immunosorbent assay (ELISA) for wildlife endocrinology studies, but no study on sea turtles has compared the results of ELISA and RIA. This study provides the first sex ratio for a threatened East Pacific green sea turtle (Chelonia mydas) foraging aggregation, a critical step for future management of this species. Here, we validate a testosterone ELISA and compare results between RIA and ELISA of duplicate samples. The ELISA demonstrated excellent correspondence with the RIA for providing testosterone concentrations for sex determination. Neither assay proved reliable for predicting the sex of reproductively active females with increased testosterone production. We then applied ELISA to examine the sex ratio of 69 green turtles foraging in San Diego Bay, California. Of 45 immature turtles sampled, sex could not be determined for three turtles because testosterone concentrations fell between the ranges for either sex (females: 4.1–113.1 pg/mL, males: 198.4–2,613.0 pg/mL) and these turtles were not subsequently recaptured to enable sex determination; using a Bayesian model to predict probabilities of turtle sex we predicted all three ‘unknowns’ were female (> 0.86). Additionally, the model assigned all turtles with their correct sex (if determined at recapture) with 100% accuracy. Results indicated a female bias (2.83F:1M) among all turtles in the aggregation; when focusing only on putative immature turtles the sex ratio was 3.5F:1M. With appropriate validation, ELISA sexing could be applied to other sea turtle species, and serve as a crucial conservation tool. PMID:26465620

Sex in an Evolutionary Perspective: Just Another Reaction Norm

PubMed Central

Nylin, Sören

2010-01-01

It is common to refer to all sorts of clear-cut differences between the sexes as something that is biologically almost inevitable. Although this does not reflect the status of evolutionary theory on sex determination and sexual dimorphism, it is probably a common view among evolutionary biologists as well, because of the impact of sexual selection theory. To get away from thinking about biological sex and traits associated with a particular sex as something static, it should be recognized that in an evolutionary perspective sex can be viewed as a reaction norm, with sex attributes being phenotypically plastic. Sex determination itself is fundamentally plastic, even when it is termed “genetic”. The phenotypic expression of traits that are statistically associated with a particular sex always has a plastic component. This plasticity allows for much more variation in the expression of traits according to sex and more overlap between the sexes than is typically acknowledged. Here we review the variation and frequency of evolutionary changes in sex, sex determination and sex roles and conclude that sex in an evolutionary time-frame is extremely variable. We draw on recent findings in sex determination mechanisms, empirical findings of morphology and behaviour as well as genetic and developmental models to explore the concept of sex as a reaction norm. From this point of view, sexual differences are not expected to generally fall into neat, discrete, pre-determined classes. It is important to acknowledge this variability in order to increase objectivity in evolutionary research. PMID:21170116

Mortality, migration, income, and air pollution: a comparative study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bozzo, S.R.; Novak, K.M.; Galdos, F.

1978-06-02

The interrelationships among different demographic factors, specific causes of death, median family income, and estimated air pollution emissions were examined. Using the Medical Data Base (MEDABA) developed at Brookhaven National Laboratory, the entire population of the United States was cross-tabulated by income and emission levels of air pollutants. Path analysis was used to examine a number of patterns and relationships for each age, race, and sex group containing a minimum of 10,000 persons. Competitive and complementary effects were observed. These effects were frequently age dependent and occasionaly sex related. This specialized data base, the application of path analysis, and themore » development of a dynamic population and mortality model, in combination, proved to be a useful tool for investigating the effects of energy related pollutants on the exposed population.« less

Sex determination in dioecious Mercurialis annua and its close diploid and polyploid relatives

PubMed Central

Russell, J R W; Pannell, J R

2015-01-01

Separate sexes have evolved on numerous independent occasions from hermaphroditic ancestors in flowering plants. The mechanisms of sex determination is known for only a handful of such species, but, in those that have been investigated, it usually involves alleles segregating at a single locus, sometimes on heteromorphic sex chromosomes. In the genus Mercurialis, transitions between combined (hermaphroditism) and separate sexes (dioecy or androdioecy, where males co-occur with hermaphrodites rather than females) have occurred more than once in association with hybridisation and shifts in ploidy. Previous work has pointed to an unusual 3-locus system of sex determination in dioecious populations. Here, we use crosses and genotyping for a sex-linked marker to reject this model: sex in diploid dioecious M. annua is determined at a single locus with a dominant male-determining allele (an XY system). We also crossed individuals among lineages of Mercurialis that differ in their ploidy and sexual system to ascertain the extent to which the same sex-determination system has been conserved following genome duplication, hybridisation and transitions between dioecy and hermaphroditism. Our results indicate that the male-determining element is fully capable of determining gender in the progeny of hybrids between different lineages. Specifically, males crossed with females or hermaphrodites always generate 1:1 male:female or male:hermaphrodite sex ratios, respectively, regardless of the ploidy levels involved (diploid, tetraploid or hexaploid). Our results throw further light on the genetics of the remarkable variation in sexual systems in the genus Mercurialis. They also illustrate the almost identical expression of sex-determining alleles in terms of sexual phenotypes across multiple divergent backgrounds, including those that have lost separate sexes altogether. PMID:25335556

Sex determination in dioecious Mercurialis annua and its close diploid and polyploid relatives.

PubMed

Russell, J R W; Pannell, J R

2015-03-01

Separate sexes have evolved on numerous independent occasions from hermaphroditic ancestors in flowering plants. The mechanisms of sex determination is known for only a handful of such species, but, in those that have been investigated, it usually involves alleles segregating at a single locus, sometimes on heteromorphic sex chromosomes. In the genus Mercurialis, transitions between combined (hermaphroditism) and separate sexes (dioecy or androdioecy, where males co-occur with hermaphrodites rather than females) have occurred more than once in association with hybridisation and shifts in ploidy. Previous work has pointed to an unusual 3-locus system of sex determination in dioecious populations. Here, we use crosses and genotyping for a sex-linked marker to reject this model: sex in diploid dioecious M. annua is determined at a single locus with a dominant male-determining allele (an XY system). We also crossed individuals among lineages of Mercurialis that differ in their ploidy and sexual system to ascertain the extent to which the same sex-determination system has been conserved following genome duplication, hybridisation and transitions between dioecy and hermaphroditism. Our results indicate that the male-determining element is fully capable of determining gender in the progeny of hybrids between different lineages. Specifically, males crossed with females or hermaphrodites always generate 1:1 male:female or male:hermaphrodite sex ratios, respectively, regardless of the ploidy levels involved (diploid, tetraploid or hexaploid). Our results throw further light on the genetics of the remarkable variation in sexual systems in the genus Mercurialis. They also illustrate the almost identical expression of sex-determining alleles in terms of sexual phenotypes across multiple divergent backgrounds, including those that have lost separate sexes altogether.

Sex determination in flowering plants: papaya as a model system.

PubMed

Aryal, Rishi; Ming, Ray

2014-03-01

Unisexuality in flowering plants evolved from a hermaphrodite ancestor. Transition from hermaphrodite to unisexual flowers has occurred multiple times across the different lineages of the angiosperms. Sexuality in plants is regulated by genetic, epigenetic and physiological mechanisms. The most specialized mechanism of sex determination is sex chromosomes. The sex chromosomes ensure the stable segregation of sexual phenotypes by preventing the recombination of sex determining genes. Despite continuous efforts, sex determining genes of dioecious plants have not yet been cloned. Concerted efforts with various model systems are necessary to understand the complex mechanism of sex determination in plants. Papaya (Carica papaya L.) is a tropical fruit tree with three sex forms, male, hermaphrodite, and female. Sexuality in papaya is determined by an XY chromosome system that is in an early evolutionary stage. The male and hermaphrodite of papaya are controlled by two different types of Y chromosomes: Y and Y(h). Large amounts of information in the area of genetics, genomics, and epigenetics of papaya have been accumulated over the last few decades. Relatively short lifecycle, small genome size, and readily available genetic and genomic resources render papaya an excellent model system to study sex determination and sex chromosomes in flowering plants. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The role of the transformer gene in sex determination and reproduction in the tephritid fruit fly, Bactrocera dorsalis (Hendel)

USDA-ARS?s Scientific Manuscript database

Transformer (tra) is a double-switch gene in the somatic sex-determination hierarchy that regulates sexual dimorphism based on RNA splicing in many insects. In tephritids, a Y-linked male determining gene (M) controls sex in the sex-determination pathway. Here, homologues of Drosophila tra and trans...

Function and evolution of sex determination mechanisms, genes and pathways in insects

PubMed Central

Gempe, Tanja; Beye, Martin

2011-01-01

Animals have evolved a bewildering diversity of mechanisms to determine the two sexes. Studies of sex determination genes – their history and function – in non-model insects and Drosophila have allowed us to begin to understand the generation of sex determination diversity. One common theme from these studies is that evolved mechanisms produce activities in either males or females to control a shared gene switch that regulates sexual development. Only a few small-scale changes in existing and duplicated genes are sufficient to generate large differences in sex determination systems. This review summarises recent findings in insects, surveys evidence of how and why sex determination mechanisms can change rapidly and suggests fruitful areas of future research. PMID:21110346

Insect sex determination: it all evolves around transformer.

PubMed

Verhulst, Eveline C; van de Zande, Louis; Beukeboom, Leo W

2010-08-01

Insects exhibit a variety of sex determining mechanisms including male or female heterogamety and haplodiploidy. The primary signal that starts sex determination is processed by a cascade of genes ending with the conserved switch doublesex that controls sexual differentiation. Transformer is the doublesex splicing regulator and has been found in all examined insects, indicating its ancestral function as a sex-determining gene. Despite this conserved function, the variation in transformer nucleotide sequence, amino acid composition and protein structure can accommodate a multitude of upstream sex determining signals. Transformer regulation of doublesex and its taxonomic distribution indicate that the doublesex-transformer axis is conserved among all insects and that transformer is the key gene around which variation in sex determining mechanisms has evolved.

Amh and Dmrta2 genes map to tilapia (Oreochromis spp.) linkage group 23 within quantitative trait locus regions for sex determination.

PubMed

Shirak, Andrey; Seroussi, Eyal; Cnaani, Avner; Howe, Aimee E; Domokhovsky, Raisa; Zilberman, Noam; Kocher, Thomas D; Hulata, Gideon; Ron, Micha

2006-11-01

Recent studies have revealed that the major genes of the mammalian sex determination pathway are also involved in sex determination of fish. Several studies have reported QTL in various species and strains of tilapia, regions contributing to sex determination have been identified on linkage groups 1, 3, and 23. Genes contributing to sex-specific mortality have been detected on linkage groups 2, 6, and 23. To test whether the same genes might control sex determination in mammals and fishes, we mapped 11 genes that are considered putative master key regulators of sex determination: Amh, Cyp19, Dax1, Dmrt2, Dmrta2, Fhl3l, Foxl2, Ixl, Lhx9, Sf1, and Sox8. We identified polymorphisms in noncoding regions of these genes and genotyped these sites for 90 individuals of an F2 mapping family. Mapping of Dax1 joined LG16 and LG21 into a single linkage group. The Amh and Dmrta2 genes were mapped to two distinct regions of LG23. The Amh gene was mapped 5 cM from UNH879 within a QTL region for sex determination and 2 cM from UNH216 within a QTL region for sex-specific mortality. Dmrta2 was mapped 4 cM from UNH848 within another QTL region for sex determination. Cyp19 was mapped to LG1 far from a previously reported QTL region for sex determination on this chromosome. Seven other candidate genes mapped to LG4, -11, -12, -14, and -17.

Vertebrate sex-determining genes play musical chairs.

PubMed

Pan, Qiaowei; Anderson, Jennifer; Bertho, Sylvain; Herpin, Amaury; Wilson, Catherine; Postlethwait, John H; Schartl, Manfred; Guiguen, Yann

2016-01-01

Sexual reproduction is one of the most highly conserved processes in evolution. However, the genetic and cellular mechanisms making the decision of whether the undifferentiated gonad of animal embryos develops either towards male or female are manifold and quite diverse. In vertebrates, sex-determining mechanisms range from environmental to simple or complex genetic mechanisms and different mechanisms have evolved repeatedly and independently. In species with simple genetic sex-determination, master sex-determining genes lying on sex chromosomes drive the gonadal differentiation process by switching on a developmental program, which ultimately leads to testicular or ovarian differentiation. So far, very few sex-determining genes have been identified in vertebrates and apart from mammals and birds, these genes are apparently not conserved over a larger number of related orders, families, genera, or even species. To fill this knowledge gap and to better explore genetic sex-determination, we propose a strategy (RAD-Sex) that makes use of next-generation sequencing technology to identify genetic markers that define sex-specific segments of the male or female genome. Copyright © 2016 Académie des sciences. All rights reserved.

Sex determination in horses - current status and future perspectives.

PubMed

Aurich, Christine; Schneider, Jana

2014-04-01

In the equine species, sex determination of the conceptus is of growing interest for the breeding industry. In horses, the sex ratio of the offspring depends on changes in body condition of the mother at conception and under natural conditions may thus markedly deviate from an expected 1:1 ratio. Insemination with sex-sorted spermatozoa allows a pronounced shift of the sex ratio but at present pregnancy rates are low and vary considerably under field conditions. In equine embryo transfer programmes, sex determination in embryos before transfer via genetic methods is a promising approach with high reliability. In ongoing pregnancies, fetal sex can be determined in utero by transrectal or transabdominal ultrasound between days 57 and 220 after ovulation, but experience is required to achieve satisfying accuracy. Recently, genetic sexing via identification of circulating cell-free fetal DNA in the maternal circulation has been successfully performed in the last three months of pregnancy. Development of this technique may also allow fetal sex determination at earlier stages of pregnancy. Further research is required to allow for techniques that enable sex determination in equine embryos as well as in ongoing pregnancies under field conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Deciphering the link between doubly uniparental inheritance of mtDNA and sex determination in bivalves: Clues from comparative transcriptomics

USGS Publications Warehouse

Capt, Charlotte; Renaut, Sébastien; Ghiselli, Fabrizio; Milani, Liliana; Johnson, Nathan A.; Sietman, Bernard E.; Stewart, Donald; Breton, Sophie

2018-01-01

Bivalves exhibit an astonishing diversity of sexual systems and sex-determining mechanisms. They can be gonochoric, hermaphroditic or androgenetic, with both genetic and environmental factors known to determine or influence sex. One unique sex-determining system involving the mitochondrial genome has also been hypothesized to exist in bivalves with doubly uniparental inheritance (DUI) of mtDNA. However, the link between DUI and sex determination remains obscure. In this study, we performed a comparative gonad transcriptomics analysis for two DUI-possessing freshwater mussel species to better understand the mechanisms underlying sex determination and DUI in these bivalves. We used a BLAST reciprocal analysis to identify orthologs between Venustaconcha ellipsiformis and Utterbackia peninsularis and compared our results with previously published sex-specific bivalve transcriptomes to identify conserved sex-determining genes. We also compared our data with other DUI species to identify candidate genes possibly involved in the regulation of DUI. A total of ∼12,000 orthologous relationships were found, with 2,583 genes differentially expressed in both species. Among these genes, key sex-determining factors previously reported in vertebrates and in bivalves (e.g., Sry, Dmrt1, Foxl2) were identified, suggesting that some steps of the sex-determination pathway may be deeply conserved in metazoans. Our results also support the hypothesis that a modified ubiquitination mechanism could be responsible for the retention of the paternal mtDNA in male bivalves, and revealed that DNA methylation could also be involved in the regulation of DUI. Globally, our results suggest that sets of genes associated with sex determination and DUI are similar in distantly-related DUI species.

Deciphering the Link between Doubly Uniparental Inheritance of mtDNA and Sex Determination in Bivalves: Clues from Comparative Transcriptomics.

PubMed

Capt, Charlotte; Renaut, Sébastien; Ghiselli, Fabrizio; Milani, Liliana; Johnson, Nathan A; Sietman, Bernard E; Stewart, Donald T; Breton, Sophie

2018-02-01

Bivalves exhibit an astonishing diversity of sexual systems and sex-determining mechanisms. They can be gonochoric, hermaphroditic or androgenetic, with both genetic and environmental factors known to determine or influence sex. One unique sex-determining system involving the mitochondrial genome has also been hypothesized to exist in bivalves with doubly uniparental inheritance (DUI) of mtDNA. However, the link between DUI and sex determination remains obscure. In this study, we performed a comparative gonad transcriptomics analysis for two DUI-possessing freshwater mussel species to better understand the mechanisms underlying sex determination and DUI in these bivalves. We used a BLAST reciprocal analysis to identify orthologs between Venustaconcha ellipsiformis and Utterbackia peninsularis and compared our results with previously published sex-specific bivalve transcriptomes to identify conserved sex-determining genes. We also compared our data with other DUI species to identify candidate genes possibly involved in the regulation of DUI. A total of ∼12,000 orthologous relationships were found, with 2,583 genes differentially expressed in both species. Among these genes, key sex-determining factors previously reported in vertebrates and in bivalves (e.g., Sry, Dmrt1, Foxl2) were identified, suggesting that some steps of the sex-determination pathway may be deeply conserved in metazoans. Our results also support the hypothesis that a modified ubiquitination mechanism could be responsible for the retention of the paternal mtDNA in male bivalves, and revealed that DNA methylation could also be involved in the regulation of DUI. Globally, our results suggest that sets of genes associated with sex determination and DUI are similar in distantly-related DUI species. © The Author(s) 2018. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Deciphering the Link between Doubly Uniparental Inheritance of mtDNA and Sex Determination in Bivalves: Clues from Comparative Transcriptomics

PubMed Central

Renaut, Sébastien; Milani, Liliana; Johnson, Nathan A; Sietman, Bernard E; Stewart, Donald T

2018-01-01

Abstract Bivalves exhibit an astonishing diversity of sexual systems and sex-determining mechanisms. They can be gonochoric, hermaphroditic or androgenetic, with both genetic and environmental factors known to determine or influence sex. One unique sex-determining system involving the mitochondrial genome has also been hypothesized to exist in bivalves with doubly uniparental inheritance (DUI) of mtDNA. However, the link between DUI and sex determination remains obscure. In this study, we performed a comparative gonad transcriptomics analysis for two DUI-possessing freshwater mussel species to better understand the mechanisms underlying sex determination and DUI in these bivalves. We used a BLAST reciprocal analysis to identify orthologs between Venustaconcha ellipsiformis and Utterbackia peninsularis and compared our results with previously published sex-specific bivalve transcriptomes to identify conserved sex-determining genes. We also compared our data with other DUI species to identify candidate genes possibly involved in the regulation of DUI. A total of ∼12,000 orthologous relationships were found, with 2,583 genes differentially expressed in both species. Among these genes, key sex-determining factors previously reported in vertebrates and in bivalves (e.g., Sry, Dmrt1, Foxl2) were identified, suggesting that some steps of the sex-determination pathway may be deeply conserved in metazoans. Our results also support the hypothesis that a modified ubiquitination mechanism could be responsible for the retention of the paternal mtDNA in male bivalves, and revealed that DNA methylation could also be involved in the regulation of DUI. Globally, our results suggest that sets of genes associated with sex determination and DUI are similar in distantly-related DUI species. PMID:29360964

Nutrient Content And Acceptability Of Snakehead-Fish (Ophiocephalus Striatus) And Pumpkin (Cucurbita Moschata) Based Complementary Foods

NASA Astrophysics Data System (ADS)

Ratna Noer, Etika; Candra, Aryu; Panunggal, Binar

2017-02-01

Poor nutrient-dense complementary foods is one of the common factors contributed for decline growth pattern in children. Snakehead-fish and Pumpkin Complementary Feeding (SPCF) base on locally food can help to reduce child malnutrition. Specifically, high protein and vitamin A in SPCF may improve immunity and nutrition status of malnutrition children. This study aimed to formulate low-cost, nutritive value and acceptable of SPCF on malnutrition children in coastal area. Carbohydrate content was determined by difference, protein by Kjeldahl, betacaroten by spectofotometri and sensory evaluation using a five point hedonic scale. Fe and zinc was determined by AAS. There is an effect of the substitution of snake-head fish flour and yellow pumpkin flour toward the nutrient content and the acceptability

Inherited XX sex reversal originating from wild medaka populations.

PubMed

Shinomiya, A; Otake, H; Hamaguchi, S; Sakaizumi, M

2010-11-01

The teleost fish, medaka (Oryzias latipes), has an XX/XY sex-determining mechanism. A Y-linked DM domain gene, DMY, has been isolated by positional cloning as the sex-determining gene in this species. Previously, we conducted a field survey of genotypic sex and found that approximately 1% of wild medaka are sex-reversed (XX males and XY females). Here, we performed genetic analyses of nine spontaneous XX sex-reversed males to elucidate its genetic basis. In all cases, the F(1) progeny were all females, whereas XX males reappeared in the backcross (BC) progeny, suggesting that XX sex reversal is a recessive trait. Although the incidences of sex reversal in the BC progeny were mostly low, 40% were males derived from one XX male. We performed linkage analysis using 55 BC males and located a single major factor, sda-1 (sex-determining autosomal factor-1), controlling sex reversal in an autosomal linkage group. Thus, genes involved in the sex-determining pathway can be isolated from spontaneous mutants in wild populations.

Autosomal gsdf acts as a male sex initiator in the fish medaka

PubMed Central

Zhang, Xi; Guan, Guijun; Li, Mingyou; Zhu, Feng; Liu, Qizhi; Naruse, Kiyoshi; Herpin, Amaury; Nagahama, Yoshitaka; Li, Jiale; Hong, Yunhan

2016-01-01

Sex is pivotal for reproduction, healthcare and evolution. In the fish medaka, the Y-chromosomal dmy (also dmrt1bY) serves the sex determiner, which activates dmrt1 for male sex maintenance. However, how dmy makes the male decision via initiating testicular differentiation has remained unknown. Here we report that autosomal gsdf serves a male sex initiator. Gene addition and deletion revealed that gsdf was necessary and sufficient for maleness via initiating testicular differentiation. We show that gsdf transcription is activated directly by dmy. These results establish the autosomal gsdf as the first male sex initiator. We propose that dmy determines maleness through activating gsdf and dmrt1 without its own participation in developmental processes of sex initiation and maintenance. gsdf may easily become a sex determiner or other autosomal genes can be recruited as new sex determiners to initiate gsdf expression. Our findings offer new insights into molecular mechanisms underlying sex development and evolution of sex-controlling genes in vertebrates. PMID:26813267

Genomic analysis of the Pacific oyster (Crassostrea gigas) reveals possible conservation of vertebrate sex determination in a mollusc.

PubMed

Zhang, Na; Xu, Fei; Guo, Ximing

2014-09-11

Despite the prevalence of sex in animal kingdom, we have only limited understanding of how sex is determined and evolved in many taxa. The mollusc Pacific oyster Crassostrea gigas exhibits complex modes of sexual reproduction that consists of protandric dioecy, sex change, and occasional hermaphroditism. This complex system is controlled by both environmental and genetic factors through unknown molecular mechanisms. In this study, we investigated genes related to sex-determining pathways in C. gigas through transcriptome sequencing and analysis of female and male gonads. Our analysis identified or confirmed novel homologs in the oyster of key sex-determining genes (SoxH or Sry-like and FoxL2) that were thought to be vertebrate-specific. Their expression profile in C. gigas is consistent with conserved roles in sex determination, under a proposed model where a novel testis-determining CgSoxH may serve as a primary regulator, directly or indirectly interacting with a testis-promoting CgDsx and an ovary-promoting CgFoxL2. Our findings plus previous results suggest that key vertebrate sex-determining genes such as Sry and FoxL2 may not be inventions of vertebrates. The presence of such genes in a mollusc with expression profiles consistent with expected roles in sex determination suggest that sex determination may be deeply conserved in animals, despite rapid evolution of the regulatory pathways that in C. gigas may involve both genetic and environmental factors. Copyright © 2014 Zhang et al.

Genomic Analysis of the Pacific Oyster (Crassostrea gigas) Reveals Possible Conservation of Vertebrate Sex Determination in a Mollusc

PubMed Central

Zhang, Na; Xu, Fei; Guo, Ximing

2014-01-01

Despite the prevalence of sex in animal kingdom, we have only limited understanding of how sex is determined and evolved in many taxa. The mollusc Pacific oyster Crassostrea gigas exhibits complex modes of sexual reproduction that consists of protandric dioecy, sex change, and occasional hermaphroditism. This complex system is controlled by both environmental and genetic factors through unknown molecular mechanisms. In this study, we investigated genes related to sex-determining pathways in C. gigas through transcriptome sequencing and analysis of female and male gonads. Our analysis identified or confirmed novel homologs in the oyster of key sex-determining genes (SoxH or Sry-like and FoxL2) that were thought to be vertebrate-specific. Their expression profile in C. gigas is consistent with conserved roles in sex determination, under a proposed model where a novel testis-determining CgSoxH may serve as a primary regulator, directly or indirectly interacting with a testis-promoting CgDsx and an ovary-promoting CgFoxL2. Our findings plus previous results suggest that key vertebrate sex-determining genes such as Sry and FoxL2 may not be inventions of vertebrates. The presence of such genes in a mollusc with expression profiles consistent with expected roles in sex determination suggest that sex determination may be deeply conserved in animals, despite rapid evolution of the regulatory pathways that in C. gigas may involve both genetic and environmental factors. PMID:25213692

Effort-reward imbalance, procedural injustice and relational injustice as psychosocial predictors of health: complementary or redundant models?

PubMed

Kivimäki, Mika; Vahtera, Jussi; Elovainio, Marko; Virtanen, Marianna; Siegrist, Johannes

2007-10-01

Effort-reward imbalance at work is an established psychosocial risk factor but there are also newer conceptualisations, such as procedural injustice (decisions at work lack consistency, openness and input from all affected parties) and relational injustice (problems in considerate and fair treatment of employees by supervisors). The authors examined whether procedural injustice and relational injustice are associated with employee health in addition to, and in combination with, effort-reward imbalance. Prospective survey data from two cohorts related to public-sector employees: the 10-Town study (n = 18 066 (78% women, age range 19-62) and the Finnish Hospital Personnel study (n = 4833, 89% women, age range 20-60). Self-rated poor health, minor psychiatric morbidity and doctor-diagnosed depression were assessed at baseline (2000-2) and at follow-up (2004). To determine incident morbidity, baseline cases were excluded. In multivariate models including age, sex, occupational status and all three psychosocial factors as predictors, high effort-reward imbalance and either high procedural injustice or high relational injustice were associated with increased morbidity at follow-up in both cohorts. After combining procedural and relational injustice into a single measure of organisational injustice, high effort-reward imbalance and high injustice were both independently associated with health. For all outcome measures, a combination of high effort-reward imbalance and high organisational injustice was related to a greater health risk than high effort-reward imbalance or injustice alone. Evidence from two independent occupational cohorts suggests that procedural and relational components of injustice, as a combined index, and effort-reward imbalance are complementary risk factors.

The maintenance of sex: Ronald Fisher meets the Red Queen.

PubMed

Green, David; Mason, Chris

2013-08-21

Sex in higher diploids carries a two-fold cost of males that should reduce its fitness relative to cloning, and result in its extinction. Instead, sex is widespread and clonal species face early obsolescence. One possible reason is that sex is an adaptation that allows organisms to respond more effectively to endless changes in their environment. The purpose of this study was to model mutation and selection in a diploid organism in an evolving environment and ascertain their support for sex. We used a computational approach to model finite populations where a haploid environment subjects a diploid host to endlessly evolving change. Evolution in both populations is primarily through adoption of novel advantageous mutations within a large allele space. Sex outcompetes cloning by two complementary mechanisms. First, sexual diploids adopt advantageous homozygous mutations more rapidly than clonal ones under conditions of lag load (the gap between the actual adaptation of the diploid population and its theoretical optimum). This rate advantage can offset the higher fecundity of cloning. Second, a relative advantage to sex emerges where populations are significantly polymorphic, because clonal polymorphism runs the risk of clonal interference caused by selection on numerous lines of similar adaptation. This interference extends allele lifetime and reduces the rate of adaptation. Sex abolishes the interference, making selection faster and elevating population fitness. Differences in adaptation between sexual and clonal populations increase markedly with the number of loci under selection, the rate of mutation in the host, and a rapidly evolving environment. Clonal interference in these circumstances leads to conditions where the greater fecundity of clones is unable to offset their poor adaptation. Sexual and clonal populations then either co-exist, or sex emerges as the more stable evolutionary strategy. Sex can out-compete clones in a rapidly evolving environment, such as that characterized by pathogens, where clonal interference reduces the adaptation of clonal populations and clones adopt advantageous mutations more slowly. Since all organisms carry parasitic loads, the model is of potentially general applicability.

Transitions between sex-determining systems in reptiles and amphibians.

PubMed

Sarre, Stephen D; Ezaz, Tariq; Georges, Arthur

2011-01-01

Important technological advances in genomics are driving a new understanding of the evolution of sex determination in vertebrates. In particular, comparative chromosome mapping in reptiles has shown an intriguing distribution of homology in sex chromosomes across reptile groups. When this new understanding is combined with the widespread distribution of genetic and temperature-dependent sex-determination mechanisms among reptiles, it is apparent that transitions between modes have occurred many times, as they have for amphibians (particularly between male and female heterogamety). It is also likely that thermosensitivity in sex determination is a key factor in those transitions in reptiles, and possibly in amphibians too. New models of sex determination involving temperature thresholds are providing the framework for the investigation of transitions and making possible key predictions about the homologies and sex-determination patterns expected among taxa in these groups. Molecular cytogenetics and other genomic approaches are essential to providing the fundamental material necessary to make advances in this field.

Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses

PubMed Central

Neckameyer, Wendi S.

2014-01-01

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. PMID:24789992

Missing female fetus: a micro level investigation of sex determination in a periurban area of Northern India.

PubMed

Ghosh, Rohini; Sharma, Arun Kumar

2012-01-01

A micro-level investigation of 983 pregnant women (aged 15-49 years) regarding sex determination and associated factors was carried out in a periurban region of Northern India. Among the women surveyed, 183 chose to use sex determination. The highest percentage of sex determination was among 30-39-year-old women, and general caste and family size were two risk factors associated with sex determination. Correcting imbalances in sex ratios at birth is a complex issue without easy answers, especially in patriarchal societies. Apart from raising awareness among decisionmakers, property rights in favor of women and strict vigilance and record of registration of ultrasound machines are necessary.

Mud crab ecology encourages site-specific approaches to fishery management

NASA Astrophysics Data System (ADS)

Dumas, P.; Léopold, M.; Frotté, L.; Peignon, C.

2012-01-01

Little is known about the effects of mud crabs population patterns on their exploitation. We used complementary approaches (experimental, fisher-based) to investigate how small-scale variations in density, size and sex-ratio related to the ecology of S. serrata may impact fishing practices in New Caledonia. Crabs were measured/sexed across 9 stations in contrasted mangrove systems between 2007 and 2009. Stations were described and classified in different kinds of mangrove forests (coastal, riverine, and estuarine); vegetation cover was qualitatively described at station scale. Annual catch was used as an indicator of fishing pressure. Middle-scale environmental factors (oceanic influence, vegetation cover) had significant contributions to crab density (GLM, 84.8% of variance), crab size and sex-ratio (< 30%). While small-scale natural factors contributed significantly to population structure, current fishing levels had no impacts on mud crabs. The observed, ecologically-driven heterogeneity of crab resource has strong social implications in the Pacific area, where land tenure system and traditional access rights prevent most fishers from freely selecting their harvest zones. This offers a great opportunity to encourage site-specific management of mud crab fisheries.

Complementary and alternative medicine use in children with cystic fibrosis.

PubMed

Giangioppo, Sandra; Kalaci, Odion; Radhakrishnan, Arun; Fleischer, Erin; Itterman, Jennifer; Lyttle, Brian; Price, April; Radhakrishnan, Dhenuka

2016-11-01

To estimate the overall prevalence of complementary and alternative medicine use among children with cystic fibrosis, determine specific modalities used, predictors of use and subjective helpfulness or harm from individual modalities. Of 53 children attending the cystic fibrosis clinic in London, Ontario (100% recruitment), 79% had used complementary and alternative medicine. The most commonly used modalities were air purifiers, humidifiers, probiotics, and omega-3 fatty acids. Family complementary and alternative medicine use was the only independent predictor of overall use. The majority of patients perceived benefit from specific modalities for cystic fibrosis symptoms. Given the high frequency and number of modalities used and lack of patient and disease characteristics predicting use, we recommend that health care providers should routinely ask about complementary and alternative medicine among all pediatric cystic fibrosis patients and assist patients in understanding the potential benefits and risks to make informed decisions about its use. Copyright © 2016 Elsevier Ltd. All rights reserved.

Complementary and alternative medicine in pregnancy: a survey of North Carolina certified nurse-midwives.

PubMed

Allaire, A D; Moos, M K; Wells, S R

2000-01-01

To determine the prevalence and types of complementary and alternative medicine therapies used by certified nurse-midwives in North Carolina. Surveys were sent to all 120 licensed certified nurse-midwives in North Carolina requesting information concerning their recommendations for use of complementary and alternative medicine for their pregnant or postpartum patients. Eighty-two responses were received (68.3%). Seventy-seven (93.9%) reported recommending complementary and alternative medicine to their pregnant patients in the past year. Forty-seven (57.3%) reported recommending complementary and alternative medicine to more than 10% of patients. The percentage of nurse-midwives who recommended each type of complementary and alternative medicine was as follows: herbal therapy (73.2%), massage therapy (67.1%), chiropractic (57.3%), acupressure (52.4%), mind-body interventions (48.8%), aromatherapy (32.9%), homeopathy (30.5%), spiritual healing (23.2%), acupuncture (19.5%), and bioelectric or magnetic applications (14.6%). The 60 respondents who reported prescribing herbal therapies gave them for the following indications: nausea and vomiting, labor stimulation, perineal discomfort, lactation disorders, postpartum depression, preterm labor, postpartum hemorrhage, labor analgesia, and malpresentation. Complementary and alternative medicine, especially herbal therapy, is commonly prescribed to pregnant women by nurse-midwives in North Carolina.

Sry and SoxE genes: How they participate in mammalian sex determination and gonadal development?

PubMed

She, Zhen-Yu; Yang, Wan-Xi

2017-03-01

In mammals, sex determination defines the differentiation of the bipotential genital ridge into either testes or ovaries. Sry, the mammalian Y-chromosomal testis-determining gene, is a master regulator of male sex determination. It acts to switch the undifferentiated genital ridge towards testis development, triggering the adoption of a male fate. Sry initiates a cascade of gene networks through the direct regulation of Sox9 expression and promotes supporting cell differentiation, Leydig cell specification, vasculature formation and testis cord development. In the absence of Sry, alternative genetic cascades, including female sex-determining genes RSPO1, Wnt4/β-catenin and Foxl2, are involved in the formation of female genitalia and the maintenance of female ovarian development. The mutual antagonisms between male and female sex-determining pathways are crucial in not just the initiation but also the maintenance of the somatic sex of the gonad throughout the organism's lifetime. Any imbalances in above sex-determining genes can cause disorders of sex development in humans and mice. In this review, we provide a detailed summary of the expression profiles, biochemical properties and developmental functions of Sry and SoxE genes in embryonic testis development and adult gonadal development. We also briefly summarize the dedicate balances between male and female sex-determining genes in mammalian sex development, with particular highlights on the molecular actions of Sry and Sox9 transcription factors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Digital transcriptome analysis of putative sex-determination genes in papaya (Carica papaya).

PubMed

Urasaki, Naoya; Tarora, Kazuhiko; Shudo, Ayano; Ueno, Hiroki; Tamaki, Moritoshi; Miyagi, Norimichi; Adaniya, Shinichi; Matsumura, Hideo

2012-01-01

Papaya (Carica papaya) is a trioecious plant species that has male, female and hermaphrodite flowers on different plants. The primitive sex chromosomes genetically determine the sex of the papaya. Although draft sequences of the papaya genome are already available, the genes for sex determination have not been identified, likely due to the complicated structure of its sex-chromosome sequences. To identify the candidate genes for sex determination, we conducted a transcriptome analysis of flower samples from male, female and hermaphrodite plants using high-throughput SuperSAGE for digital gene expression analysis. Among the short sequence tags obtained from the transcripts, 312 unique tags were specifically mapped to the primitive sex chromosome (X or Y(h)) sequences. An annotation analysis revealed that retroelements are the most abundant sequences observed in the genes corresponding to these tags. The majority of tags on the sex chromosomes were located on the X chromosome, and only 30 tags were commonly mapped to both the X and Y(h) chromosome, implying a loss of many genes on the Y(h) chromosome. Nevertheless, candidate Y(h) chromosome-specific female determination genes, including a MADS-box gene, were identified. Information on these sex chromosome-specific expressed genes will help elucidating sex determination in the papaya.

Digital Transcriptome Analysis of Putative Sex-Determination Genes in Papaya (Carica papaya)

PubMed Central

Urasaki, Naoya; Tarora, Kazuhiko; Shudo, Ayano; Ueno, Hiroki; Tamaki, Moritoshi; Miyagi, Norimichi; Adaniya, Shinichi; Matsumura, Hideo

2012-01-01

Papaya (Carica papaya) is a trioecious plant species that has male, female and hermaphrodite flowers on different plants. The primitive sex chromosomes genetically determine the sex of the papaya. Although draft sequences of the papaya genome are already available, the genes for sex determination have not been identified, likely due to the complicated structure of its sex-chromosome sequences. To identify the candidate genes for sex determination, we conducted a transcriptome analysis of flower samples from male, female and hermaphrodite plants using high-throughput SuperSAGE for digital gene expression analysis. Among the short sequence tags obtained from the transcripts, 312 unique tags were specifically mapped to the primitive sex chromosome (X or Yh) sequences. An annotation analysis revealed that retroelements are the most abundant sequences observed in the genes corresponding to these tags. The majority of tags on the sex chromosomes were located on the X chromosome, and only 30 tags were commonly mapped to both the X and Yh chromosome, implying a loss of many genes on the Yh chromosome. Nevertheless, candidate Yh chromosome-specific female determination genes, including a MADS-box gene, were identified. Information on these sex chromosome-specific expressed genes will help elucidating sex determination in the papaya. PMID:22815863

Frontal sinus parameters in computed tomography and sex determination.

PubMed

Akhlaghi, Mitra; Bakhtavar, Khadijeh; Moarefdoost, Jhale; Kamali, Artin; Rafeifar, Shahram

2016-03-01

The frontal sinus is a sturdy part of the skull that is likely to be retrieved for forensic investigations. We evaluated frontal sinus parameters in paranasal sinus computed tomography (CT) images for sex determination. The study was conducted on 200 normal paranasal sinus CT images of 100 men and 100 women of Persian origin. We categorized the studied population into three age groups of 20-34, 35-49 and ⩾ 50 years. The number of partial septa in the right frontal sinus and the maximum height and width were significantly different between the two sexes. The highest precision for sex determination was for the maximum height of the left frontal sinus (61.3%). In the 20-34 years age-group, height and width of the frontal sinus were significantly different between the two sexes and the height of the left sinus had the highest precision (60.8%). In the 35-49 years age-group, right anterior-posterior diameter had a sex determination precision of 52.3%. No frontal sinus parameter reached a statistically significant level for sex determination in the ⩾ 50 years age-group. The number of septa and scallopings were not useful in sex determination. Frontal sinus parameters did not have a high precision in sex determination among Persian adults. Copyright © 2016. Published by Elsevier Ireland Ltd.

Gender-Associated Mitochondrial DNA Heteroplasmy in Somatic Tissues of the Endangered Freshwater Mussel Unio crassus (Bivalvia: Unionidae): Implications for Sex Identification and Phylogeographical Studies.

PubMed

Mioduchowska, Monika; Kaczmarczyk, Agnieszka; Zając, Katarzyna; Zając, Tadeusz; Sell, Jerzy

2016-11-01

Some bivalve species possess two independent mitochondrial DNA lineages: maternally (F-type) and paternally (M-type) inherited. This phenomenon is called doubly uniparental inheritance. It is generally agreed that F-type mtDNA is typically present in female somatic and gonadal tissues as well as in male somatic tissues, whereas the M-type mtDNA occurs only in male germ line and gonadal tissue. In the present study, the mtDNA heteroplasmy (for both F and M genomes) in male somatic tissues of Unio crassus (Philipsson, 1788), species threatened with extinction, has been confirmed. Taking advantage from the presence of Mcox1 marker only in male somatic tissues, we developed a new method of sex identification in this endangered species, using nondestructive tissue sampling. Probability of correct sex identification was estimated at 97.5%. The present study is the first report on gender-associated mitochondrial DNA heteroplasmy in male somatic tissues of thick-shelled river mussel and first approach to U. crassus sex identification at molecular level. Our study also confirmed the utility of paternally inherited Mcox1 gene fragment as a complementary molecular tool for resolving phylogeographical relationships among populations of thick-shelled river mussel. © 2017 Wiley Periodicals, Inc.

Prevalence and determinants of complementary and alternative medicine use among infertile patients in Lebanon: a cross sectional study

PubMed Central

2012-01-01

Background Complementary and alternative medicine (CAM) is widely used for the treatment of infertility. While the Middle East and North Africa region has been shown to house one of the fastest growing markets of CAM products in the world, research describing the use of CAM therapies among Middle-Eastern infertile patients is minimal. The aim of this study is to examine the prevalence, characteristics and determinants of CAM use among infertile patients in Lebanon. Methods A cross sectional survey design was used to carry out face-to-face interviews with 213 consecutive patients attending the Assisted Reproductive Unit at a major academic medical center in Beirut. The questionnaire comprised three sections: socio-demographic and lifestyle characteristics, infertility-related aspects and information on CAM use. The main outcome measure was the use of CAM modalities for infertility treatment. Determinants of CAM use were assessed through the logistic regression method. Results Overall, 41% of interviewed patients reported using a CAM modality at least once for their infertility. There was a differential by gender in the most commonly used CAM therapies; where males mostly used functional foods (e.g. honey & nuts) (82.9%) while females mostly relied on spiritual healing/prayer (56.5%). Factors associated with CAM use were higher household income (OR: 0.305, 95% CI: 0.132–0.703) and sex, with females using less CAM than males (OR: 0.12, 95% CI: 0.051–0.278). The older patients were diagnosed with infertility, the lower the odds of CAM use (p for trend <0.05). Almost half of the participants (48%) were advised on CAM use by their friends, and only 13% reported CAM use to their physician. Conclusions The considerably high use of CAM modalities among Lebanese infertile patients, added to a poor CAM use disclosure to physicians, underscore the need to integrate CAM into the education and training of health professionals, as well as enhance infertile patients' awareness on safe use of CAM products. PMID:22901284

Molecular and cellular sex differences at the intersection of stress and arousal.

PubMed

Valentino, Rita J; Reyes, Beverly; Van Bockstaele, Elisabeth; Bangasser, Debra

2012-01-01

Elucidating the mechanisms underlying sex biases in the prevalence and severity of diseases can advance our understanding of their pathophysiological basis and serve as a guide for developing treatments. A well-established sex difference in psychiatry is the higher incidence of mood and anxiety disorders in females. These disorders share stress as a potential etiological contributor and hyperarousal as a core symptom, suggesting that the distinction between sexes lies at the intersection of stress and arousal systems. This review focuses on the link between the stress axis and the brain norepinephrine arousal system as a key point at which sex differences occur and are translated to differences in the expression of mood disorders. Evidence for a circuit designed to relay emotion-related information via the limbic corticotropin-releasing factor (CRF) system to the locus coeruleus (LC)-norepinephrine arousal system is reviewed. This is followed by recent novel findings of sex differences in CRF receptor signaling and trafficking that would result in an enhanced arousal response and a compromised ability to adapt to chronic stress in females. Finally, we discuss the evidence for sex differences in LC dendritic structure that allow for an increased receipt and processing of limbic information in females compared to males. Together these complementary sets of data suggest that in females, the LC arousal system is poised to process more limbic information and to respond to some of this information in an enhanced manner compared to males. The clinical and therapeutic considerations arising from this perspective are discussed. This article is part of a Special Issue entitled 'Anxiety and Depression'. Copyright © 2011 Elsevier Ltd. All rights reserved.

Bombyx mori histone methyltransferase BmAsh2 is essential for silkworm piRNA-mediated sex determination.

PubMed

Li, Zhiqian; You, Lang; Yan, Dong; James, Anthony A; Huang, Yongping; Tan, Anjiang

2018-02-01

Sex determination is a hierarchically-regulated process with high diversity in different organisms including insects. The W chromosome-derived Fem piRNA has been identified as the primary sex determination factor in the lepidopteran insect, Bombyx mori, revealing a distinctive piRNA-mediated sex determination pathway. However, the comprehensive mechanism of silkworm sex determination is still poorly understood. We show here that the silkworm PIWI protein BmSiwi, but not BmAgo3, is essential for silkworm sex determination. CRISPR/Cas9-mediated depletion of BmSiwi results in developmental arrest in oogenesis and partial female sexual reversal, while BmAgo3 depletion only affects oogenesis. We identify three histone methyltransferases (HMTs) that are significantly down-regulated in BmSiwi mutant moths. Disruption one of these, BmAsh2, causes dysregulation of piRNAs and transposable elements (TEs), supporting a role for it in the piRNA signaling pathway. More importantly, we find that BmAsh2 mutagenesis results in oogenesis arrest and partial female-to-male sexual reversal as well as dysregulation of the sex determination genes, Bmdsx and BmMasc. Mutagenesis of other two HMTs, BmSETD2 and BmEggless, does not affect piRNA-mediated sex determination. Histological analysis and immunoprecipitation results support a functional interaction between the BmAsh2 and BmSiwi proteins. Our data provide the first evidence that the HMT, BmAsh2, plays key roles in silkworm piRNA-mediated sex determination.

Gonad development in Midas cichlids and the evolution of sex change in fishes.

PubMed

Oldfield, Ronald G

2011-01-01

Some fishes mature and function as one sex and later transform to the other sex in response to social interactions. Previous evidence suggested that a change in developmental timing may be involved in the evolution of adult sex change in fishes. The most recent support for this idea came from reports that sex in the Midas cichlid, Amphilophus citrinellus, was determined by social conditions experienced at the juvenile stage. Differentiation as a male was reported to be dependent on large body size relative to group-mates, and thought to be mediated through aggressive interactions. Here I demonstrate that socially controlled sex determination does not occur as was originally reported. Previously, I found that sex was not associated with body size in juveniles either in nature or in captivity. Similarly, I found no association between aggressive behavior and sex in juveniles. I later demonstrated that socially controlled sex determination does not typically occur in the Midas cichlid and closely related species and supported an alternative mechanism to explain large body size in adult males. Finally, in the current study I analyze gonad histology of fish from the same population used by the original authors and lay to rest the idea of socially controlled sex determination in this species. Recent observations of socially controlled sex determination in juveniles of species that typically change sex at the adult stage are examples of phenotypic plasticity, not genetic variation. Therefore, juvenile socially controlled sex determination does not support a theory that a change in developmental timing is involved in the evolution of adult sex change in fishes. © 2011 Wiley Periodicals, Inc.

Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses.

PubMed

Argue, Kathryn J; Neckameyer, Wendi S

2014-07-01

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. Copyright © 2014 the American Physiological Society.

Quantitative Trait Loci Involved in Sex Determination and Body Growth in the Gilthead Sea Bream (Sparus aurata L.) through Targeted Genome Scan

PubMed Central

Loukovitis, Dimitrios; Sarropoulou, Elena; Tsigenopoulos, Costas S.; Batargias, Costas; Magoulas, Antonios; Apostolidis, Apostolos P.; Chatziplis, Dimitrios; Kotoulas, Georgios

2011-01-01

Among vertebrates, teleost fish exhibit a considerably wide range of sex determination patterns that may be influenced by extrinsic parameters. However even for model fish species like the zebrafish Danio rerio the precise mechanisms involved in primary sex determination have not been studied extensively. The zebrafish, a gonochoristic species, is lacking discernible sex chromosomes and the sex of juvenile fish is difficult to determine. Sequential protandrous hermaphrodite species provide distinct determination of the gender and allow studying the sex determination process by looking at the mechanism of sex reversal. This is the first attempt to understand the genetic basis of phenotypic variation for sex determination and body weight in a sequential protandrous hermaphrodite species, the gilthead sea bream (Sparus aurata). This work demonstrates a fast and efficient strategy for Quantitative Trait Loci (QTL) detection in the gilthead sea bream, a non-model but target hermaphrodite fish species. Therefore a comparative mapping approach was performed to query syntenies against two other Perciformes, the European sea bass (Dicentrarchus labrax), a gonochoristic species and the Asian sea bass (Lates calcarifer) a protandrous hermaphrodite. In this manner two significant QTLs, one QTL affecting both body weight and sex and one QTL affecting sex, were detected on the same linkage group. The co-segregation of the two QTLs provides a genomic base to the observed genetic correlation between these two traits in sea bream as well as in other teleosts. The identification of QTLs linked to sex reversal and growth, will contribute significantly to a better understanding of the complex nature of sex determination in S. aurata where most individuals reverse to the female sex at the age of two years through development and maturation of the ovarian portion of the gonad and regression of the testicular area. [Genomic sequences reported in this manuscript have been submitted to GenBank under accession numbers HQ021443–HQ021749.] PMID:21304996

Nutritional and sensory evaluation of a complementary food formulated from rice, faba beans, sweet potato flour, and peanut oil.

PubMed

Mahmoud, Amal H; El Anany, Ayman Mohammed

2014-12-01

Childhood malnutrition is a common disorder in developing countries. To formulate a complementary food from rice, germinated-decoated faba bean, orange-fleshed sweet potato flour, and peanut oil (RFPP formula) for infants aged 6 to 24 months. The nutritional and sensory characteristics of the RFPP complementary food in comparison with those of a commercial complementary food were determined using standard official procedures. The levels of protein (17.89 g/100 g), fat (10.35 g/100 g), carbohydrate (67.82 g/100 g), and energy (435.99 kcal/100 g) of the RFPP complementary food met the specifications of the Codex standard (1991) and the Egyptian Standard No. 3284 (2005). The essential amino acid contents of the RFPP complementary food were higher than the amino acid profile of the Food and Agriculture Organization/World Health Organization/United Nations University (2002) reference protein for children 0.5 to 1 and 1 to 2 years of age. The RFPP complementary food had high levels (54.00%) of monounsaturated fatty acids. However, the highest level of saturated fatty acids (51.10%) was recorded for the commercial complementary food. The sensory evaluation results, using a nine-point hedonic scale ranging from 1 (dislike extremely) to 9 (like extremely), show that the RFPP complementary food was acceptable in appearance (7.20), color (6.35), aroma (6.75), taste (7.25), and mouthfeel (7.10) and had an overall acceptability of 6.40. The RFPP formulated complementary food was acceptable and adequate in nutrients for weaning purposes.

Efficacy of Sex Determination from Human Dental Pulp Tissue and its Reliability as a Tool in Forensic Dentistry.

PubMed

Khanna, Kaveri Surya

2015-01-01

Sex determination is one of the primary steps in forensics. Barr body can be used as a histological method for identification of sex as it is found to be specific to female somatic cells and rare in male cells. To demarcate human dental pulp as an important identification tool of sex in forensic odontology (FO) and to evaluate the time period till which sex can be determined from pulp tissue using three stains H and E, Feulgen, and acridine - orange under fluorescence so as. 90 pulp samples (45 males and 45 females) were subjected to Barr body analysis for determination of sex using light and fluorescent microscopy. Barr body was found to be positive for female samples and negative or rare in the male sample (<3%). Barr body from human dental pulp tissue can be used as a successful determinant of sex identification in FO.

Determination of sex origin of meat and meat products on the DNA basis: a review.

PubMed

Gokulakrishnan, Palanisamy; Kumar, Rajiv Ranjan; Sharma, Brahm Deo; Mendiratta, Sanjod Kumar; Malav, Omprakash; Sharma, Deepak

2015-01-01

Sex determination of domestic animal's meat is of potential value in meat authentication and quality control studies. Methods aiming at determining the sex origin of meat may be based either on the analysis of hormone or on the analysis of nucleic acids. At the present time, sex determination of meat and meat products based on hormone analysis employ gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS), and enzyme-linked immunosorbent assay (ELISA). Most of the hormone-based methods proved to be highly specific and sensitive but were not performed on a regular basis for meat sexing due to the technical limitations or the expensive equipments required. On the other hand, the most common methodology to determine the sex of meat is unquestionably traditional polymerase chain reaction (PCR) that involves gel electrophoresis of DNA amplicons. This review is intended to provide an overview of the DNA-based methods for sex determination of meat and meat products.

Protein kinase C is involved with upstream signaling of methyl farnesoate for photoperiod-dependent sex determination in the water flea Daphnia pulex

PubMed Central

Toyota, Kenji; Sato, Tomomi; Tatarazako, Norihisa

2017-01-01

ABSTRACT Sex determination of Daphnia pulex is decided by environmental conditions. We established a suitable experimental system for this study using D. pulex WTN6 strain, in which the sex of the offspring can be controlled by photoperiod. Long-day conditions induced females and short-day conditions induced males. Using this system, we previously found that methy farnesoate (MF), which is a putative innate juvenile hormone molecule in daphnids, is necessary for male sex determination and that protein kinase C (PKC) is a candidate factor of male sex determiner. In this study, we demonstrated that a PKC inhibitor [bisindolylmaleimide IV (BIM)] application strongly suppressed male offspring induction in the short-day condition. Moreover, co-treatment of BIM with MF revealed that PKC signaling acts upstream of MF signaling for male sex determination. This is the first experimental evidence that PKC is involved in the male sex determination process associated with methyl farnesoate signaling in daphnid species. PMID:27965197

Gender on the brain: a case study of science communication in the new media environment.

PubMed

O'Connor, Cliodhna; Joffe, Helene

2014-01-01

Neuroscience research on sex difference is currently a controversial field, frequently accused of purveying a 'neurosexism' that functions to naturalise gender inequalities. However, there has been little empirical investigation of how information about neurobiological sex difference is interpreted within wider society. This paper presents a case study that tracks the journey of one high-profile study of neurobiological sex differences from its scientific publication through various layers of the public domain. A content analysis was performed to ascertain how the study was represented in five domains of communication: the original scientific article, a press release, the traditional news media, online reader comments and blog entries. Analysis suggested that scientific research on sex difference offers an opportunity to rehearse abiding cultural understandings of gender. In both scientific and popular contexts, traditional gender stereotypes were projected onto the novel scientific information, which was harnessed to demonstrate the factual truth and normative legitimacy of these beliefs. Though strains of misogyny were evident within the readers' comments, most discussion of the study took pains to portray the sexes' unique abilities as equal and 'complementary'. However, this content often resembled a form of benevolent sexism, in which praise of women's social-emotional skills compensated for their relegation from more esteemed trait-domains, such as rationality and productivity. The paper suggests that embedding these stereotype patterns in neuroscience may intensify their rhetorical potency by lending them the epistemic authority of science. It argues that the neuroscience of sex difference does not merely reflect, but can actively shape the gender norms of contemporary society.

Complementary Feeding Knowledge, Practices, and Dietary Diversity among Mothers of Under-Five Children in an Urban Community in Lagos State, Nigeria

PubMed Central

Olatona, Foluke Adenike; Adenihun, Jesupelumi Oreoluwa; Aderibigbe, Sunday Adedeji; Adeniyi, Oluwafunmilayo Funke

2017-01-01

Background and Objectives: Inappropriate complementary feeding is a major cause of child malnutrition and death. This study determined the complementary feeding knowledge, practices, minimum dietary diversity, and acceptable diet among mothers of under-five children in an urban Local Government Area of Lagos State, Southwest Nigeria. Methods: This descriptive cross-sectional study was conducted in Eti-Osa area of Lagos State, Nigeria. Multi-stage sampling technique was employed to select 355 mothers and infants. Data was collected using a pre-tested interviewer administered questionnaire and 24-hour diet recall was used to assess dietary diversity. Data was analyzed using Epi-Info. Results: Knowledge of complementary feeding was low (14.9%) and was associated with older mothers’ age, being married, and higher level of education. The prevalence of timely initiation of complementary feeding (47.9%), dietary diversity (16.0%) and minimum acceptable diet for children between 6 and 9 months (16%) were low. Overall, appropriate complementary feeding practice was low (47.0%) and associated with higher level of mothers’ education and occupation. Conclusions and Global Health Implications: Complementary feeding knowledge and practices were poor among mothers of under-5 especially the non-literate. Reduction of child malnutrition through appropriate complementary feeding remains an important global health goal. Complementary feeding education targeting behavioral change especially among young, single and uneducated mothers in developing countries is important to reduce child morbidity and mortality. PMID:28798893

Identification of General Patterns of Sex-Biased Expression in Daphnia, a Genus with Environmental Sex Determination

PubMed Central

Molinier, Cécile; Reisser, Céline M.O.; Fields, Peter; Ségard, Adeline; Galimov, Yan; Haag, Christoph R.

2018-01-01

Daphnia reproduce by cyclic-parthenogenesis, where phases of asexual reproduction are intermitted by sexual production of diapause stages. This life cycle, together with environmental sex determination, allow the comparison of gene expression between genetically identical males and females. We investigated gene expression differences between males and females in four genotypes of Daphnia magna and compared the results with published data on sex-biased gene expression in two other Daphnia species, each representing one of the major phylogenetic clades within the genus. We found that 42% of all annotated genes showed sex-biased expression in D. magna. This proportion is similar both to estimates from other Daphnia species as well as from species with genetic sex determination, suggesting that sex-biased expression is not reduced under environmental sex determination. Among 7453 single copy, one-to-one orthologs in the three Daphnia species, 707 consistently showed sex-biased expression and 675 were biased in the same direction in all three species. Hence these genes represent a core-set of genes with consistent sex-differential expression in the genus. A functional analysis identified that several of them are involved in known sex determination pathways. Moreover, 75% were overexpressed in females rather than males, a pattern that appears to be a general feature of sex-biased gene expression in Daphnia. PMID:29535148

Identification of General Patterns of Sex-Biased Expression in Daphnia, a Genus with Environmental Sex Determination.

PubMed

Molinier, Cécile; Reisser, Céline M O; Fields, Peter; Ségard, Adeline; Galimov, Yan; Haag, Christoph R

2018-05-04

Daphnia reproduce by cyclic-parthenogenesis, where phases of asexual reproduction are intermitted by sexual production of diapause stages. This life cycle, together with environmental sex determination, allow the comparison of gene expression between genetically identical males and females. We investigated gene expression differences between males and females in four genotypes of Daphnia magna and compared the results with published data on sex-biased gene expression in two other Daphnia species, each representing one of the major phylogenetic clades within the genus. We found that 42% of all annotated genes showed sex-biased expression in D. magna This proportion is similar both to estimates from other Daphnia species as well as from species with genetic sex determination, suggesting that sex-biased expression is not reduced under environmental sex determination. Among 7453 single copy, one-to-one orthologs in the three Daphnia species, 707 consistently showed sex-biased expression and 675 were biased in the same direction in all three species. Hence these genes represent a core-set of genes with consistent sex-differential expression in the genus. A functional analysis identified that several of them are involved in known sex determination pathways. Moreover, 75% were overexpressed in females rather than males, a pattern that appears to be a general feature of sex-biased gene expression in Daphnia . Copyright © 2018 Molinier et al.

Genetic sex determination in Astatotilapia calliptera, a prototype species for the Lake Malawi cichlid radiation.

PubMed

Peterson, Erin N; Cline, Maggie E; Moore, Emily C; Roberts, Natalie B; Roberts, Reade B

2017-06-01

East African cichlids display extensive variation in sex determination systems. The species Astatotilapia calliptera is one of the few cichlids that reside both in Lake Malawi and in surrounding waterways. A. calliptera is of interest in evolutionary studies as a putative immediate outgroup species for the Lake Malawi species flock and possibly as a prototype ancestor-like species for the radiation. Here, we use linkage mapping to test association of sex in A. calliptera with loci that have been previously associated with genetic sex determination in East African cichlid species. We identify a male heterogametic XY system segregating at linkage group (LG) 7 in an A. calliptera line that originated from Lake Malawi, at a locus previously shown to act as an XY sex determination system in multiple species of Lake Malawi cichlids. Significant association of genetic markers and sex produce a broad genetic interval of approximately 26 megabases (Mb) using the Nile tilapia genome to orient markers; however, we note that the marker with the strongest association with sex is near a gene that acts as a master sex determiner in other fish species. We demonstrate that alleles of the marker are perfectly associated with sex in Metriaclima mbenjii, a species from the rock-dwelling clade of Lake Malawi. While we do not rule out the possibility of other sex determination loci in A. calliptera, this study provides a foundation for fine mapping of the cichlid sex determination gene on LG7 and evolutionary context regarding the origin and persistence of the LG7 XY across diverse, rapidly evolving lineages.

Genetic sex determination in Astatotilapia calliptera, a prototype species for the Lake Malawi cichlid radiation

NASA Astrophysics Data System (ADS)

Peterson, Erin N.; Cline, Maggie E.; Moore, Emily C.; Roberts, Natalie B.; Roberts, Reade B.

2017-06-01

East African cichlids display extensive variation in sex determination systems. The species Astatotilapia calliptera is one of the few cichlids that reside both in Lake Malawi and in surrounding waterways. A. calliptera is of interest in evolutionary studies as a putative immediate outgroup species for the Lake Malawi species flock and possibly as a prototype ancestor-like species for the radiation. Here, we use linkage mapping to test association of sex in A. calliptera with loci that have been previously associated with genetic sex determination in East African cichlid species. We identify a male heterogametic XY system segregating at linkage group (LG) 7 in an A. calliptera line that originated from Lake Malawi, at a locus previously shown to act as an XY sex determination system in multiple species of Lake Malawi cichlids. Significant association of genetic markers and sex produce a broad genetic interval of approximately 26 megabases (Mb) using the Nile tilapia genome to orient markers; however, we note that the marker with the strongest association with sex is near a gene that acts as a master sex determiner in other fish species. We demonstrate that alleles of the marker are perfectly associated with sex in Metriaclima mbenjii, a species from the rock-dwelling clade of Lake Malawi. While we do not rule out the possibility of other sex determination loci in A. calliptera, this study provides a foundation for fine mapping of the cichlid sex determination gene on LG7 and evolutionary context regarding the origin and persistence of the LG7 XY across diverse, rapidly evolving lineages.

Operando XRD studies as a tool for determination of transport parameters of mobile ions in electrode materials

NASA Astrophysics Data System (ADS)

Kondracki, Łukasz; Kulka, Andrzej; Świerczek, Konrad; Ziąbka, Magdalena; Molenda, Janina

2017-11-01

In this work a detailed operando XRD investigations of structural properties of LixMn2O4 manganese spinel are shown to be a complementary, successful method of determination of diffusion coefficient D and surface exchange coefficient k in the working electrode. Kinetics of lithium ions transport are estimated on the basis of rate of structural changes of the cathode material during a relaxation stage after a high current charge, i.e. during structural relaxation of the material. The presented approach seems to be applicable as a complementary method of determination of transport coefficients for all intercalation-type electrode materials.

Perceptions of HIV Self-Testing Among Men Who Have Sex With Men in the United States: A Qualitative Analysis.

PubMed

Freeman, Arin E; Sullivan, Patrick; Higa, Darrel; Sharma, Akshay; MacGowan, Robin; Hirshfield, Sabina; Greene, George J; Gravens, Laura; Chavez, Pollyanna; McNaghten, A D; Johnson, Wayne D; Mustanski, Brian

2018-02-01

HIV testing is the gateway into both prevention and treatment services. It is important to understand how men who have sex with men (MSM) perceive HIV self-tests. We conducted focus groups and individual interviews to collect feedback on two HIV self-tests, and on a dried blood spot (DBS) specimen collection kit. Perceptions and attitudes around HIV self-testing (HIVST), and willingness to distribute HIV self-tests to others were assessed. MSM reported HIVST to be complementary to facility-based testing, and liked this approach because it offers privacy and convenience, does not require counseling, and could lead to linkage to care. However, they also had concerns around the accuracy of HIV self-tests, their cost, and receiving a positive test result without immediate access to follow-up services. Despite these issues, they perceived HIVST as a positive addition to their HIV prevention toolbox.

Risk-Taking and the Feedback Negativity Response to Loss among At-Risk Adolescents

PubMed Central

Crowley, Michael J.; Wu, Jia; Crutcher, Clifford; Bailey, Christopher A.; Lejuez, C.W.; Mayes, Linda C.

2009-01-01

Event-related brain potentials were examined in 32 adolescents (50% female) from a high-risk sample, who were exposed to cocaine and other drugs prenatally. Adolescents were selected for extreme high- or low-risk behavior on the Balloon Analog Risk Task, a measure of real-world risk-taking propensity. The feedback error-related negativity (fERN), an event-related potential (ERP) that occurs when an expected reward does not occur, was examined in a game in which choices lead to monetary gains and losses with feedback delayed 1 or 2 s. The fERN was clearly visible in the fronto-central scalp region in this adolescent sample. Feedback type, feedback delay, risk status, and sex were all associated with fERN variability. Monetary feedback also elicited a P300-like component, moderated by delay and sex. Delaying reward feedback may provide a means for studying complementary functioning of dopamine and norepinephrine systems. PMID:19372694

The genetic contribution to sex determination and number of sex chromosomes vary among populations of common frogs (Rana temporaria).

PubMed

Rodrigues, N; Vuille, Y; Brelsford, A; Merilä, J; Perrin, N

2016-07-01

The patterns of sex determination and sex differentiation have been shown to differ among geographic populations of common frogs. Notably, the association between phenotypic sex and linkage group 2 (LG2) has been found to be perfect in a northern Swedish population, but weak and variable among families in a southern one. By analyzing these populations with markers from other linkage groups, we bring two new insights: (1) the variance in phenotypic sex not accounted for by LG2 in the southern population could not be assigned to genetic factors on other linkage groups, suggesting an epigenetic component to sex determination; (2) a second linkage group (LG7) was found to co-segregate with sex and LG2 in the northern population. Given the very short timeframe since post-glacial colonization (in the order of 1000 generations) and its seemingly localized distribution, this neo-sex chromosome system might be the youngest one described so far. It does not result from a fusion, but more likely from a reciprocal translocation between the original Y chromosome (LG2) and an autosome (LG7), causing their co-segregation during male meiosis. By generating a strict linkage between several important genes from the sex-determination cascade (Dmrt1, Amh and Amhr2), this neo-sex chromosome possibly contributes to the 'differentiated sex race' syndrome (strictly genetic sex determination and early gonadal development) that characterizes this northern population.

Arrays of nucleic acid probes on biological chips

DOEpatents

Chee, Mark; Cronin, Maureen T.; Fodor, Stephen P. A.; Huang, Xiaohua X.; Hubbell, Earl A.; Lipshutz, Robert J.; Lobban, Peter E.; Morris, MacDonald S.; Sheldon, Edward L.

1998-11-17

DNA chips containing arrays of oligonucleotide probes can be used to determine whether a target nucleic acid has a nucleotide sequence identical to or different from a specific reference sequence. The array of probes comprises probes exactly complementary to the reference sequence, as well as probes that differ by one or more bases from the exactly complementary probes.

Effectiveness of the National Program of Complementary Feeding for older adults in Chile on vitamin B12 status in older adults; secondary outcome analysis from the CENEX Study (ISRCTN48153354)

PubMed Central

2013-01-01

Background Older people are at increased risk of vitamin B12 deficiency and the provision of fortified foods may be an effective way to ensure good vitamin B12 status in later life. Aim To evaluate the effectiveness of a vitamin B12 fortified food provided by a national program of complementary food for older people on plasma vitamin B12 levels. Subjects and methods A random sub-sample of 351 subjects aged 65-67y from a large cluster randomised controlled trial provided blood samples at baseline and after 24 months of intervention. The intervention arm (10 clusters 186 participants) received a vitamin B12 fortified food designed to deliver 1.4 μg/day, while the control arm did not receive complementary food (10 clusters, 165 participants). Serum vitamin B12 and folate levels determined by radioimmunoassay were used to estimate the effect of intervention on vitamin B12 levels, adjusting for baseline levels and sex. Results Attrition at 24 months was 16.7% and 23.6% in the intervention and control arms respectively (p = 0.07). Over 24 months of intervention, mean (95% CI) serum vitamin B12 decreased from 392 (359–425) pmol/dL to 357 (300–414) pmol/dL (p < 0.07) in the intervention arm and from 395 (350–440) pmol/dL to 351 (308–395) pmol/dL in the control arm. There was no significant effect of the intervention on folate status. Discussion Our findings suggest that foods fortified with 1.4 μg/daily vitamin B12 as provided by Chile’s national programme for older people are insufficient to ensure adequate vitamin B12 levels in this population. Chile has a long and successful experience with nutrition intervention programs; however, the country’s changing demographic and nutritional profiles require a constant adjustment of the programs. PMID:24016218

Sexing chick mRNA: A protocol based on quantitative real-time polymerase chain reaction.

PubMed

Wan, Z; Lu, Y; Rui, L; Yu, X; Li, Z

2017-03-01

The accurate identification of sex in birds is important for research on avian sex determination and differentiation. Polymerase chain reaction (PCR)-based methods have been widely applied for the molecular sexing of birds. However, these methods have used genomic DNA. Here, we present the first sexing protocol for chick mRNA based on real-time quantitative PCR. We demonstrate that this method can accurately determine sex using mRNA from chick gonads and other tissues, such as heart, liver, spleen, lung, and muscle. The strategy of this protocol also may be suitable for other species in which sex is determined by the inheritance of sex chromosomes (ZZ male and ZW female). © 2016 Poultry Science Association Inc.

Estrogenic chemical effects are independent from the degree of sex role reversal in pipefish.

PubMed

Sárria, Marisa P; Santos, Miguel M; Castro, L Filipe C; Vieira, Natividade M; Monteiro, Nuno M

2013-12-15

Endocrine disrupting chemicals (EDCs) have been reported to disturb several ecological relevant endpoints. Surprisingly, EDC-induced effects on fish sexual behaviour have been poorly studied despite the fact that even subtle alterations might contribute to a disruption of sexual interactions, thus negatively impacting reproduction. As the few assessments on sexual behaviour have been conducted in species with orthodox sex roles, it might be argued that sex-role reversed species might provide a potentially complementary system to further explore the effects of EDCs on reproduction. In the present study, two pipefish species with distinct degrees of sex-role reversal were selected to further elucidate the impact of chronic EE2 exposure on sexual behaviour and reproduction-related endpoints. The obtained results indicate that, independently of the degree of sex role reversal, courtship behaviour seems to resist oestrogenic chemical exposure. However, exposure to environmentally relevant EE2 levels did induce a complete absence of pregnancies at 18 ng/L. Even though pregnancies were observed at intermediate concentrations, the percentage of non-transferred or misplaced oocytes increased and a dose-dependent decrease of oocyte volume was observed. Imbalances in the oogenesis process, induction of vitellogenin in males and the absence of pregnancies highlight that environmental relevant concentrations of EE2 have the potential to negatively affect pipefish populations, most of them inhabiting coastal areas where oestrogenic contamination is more prevalent. Copyright © 2013 Elsevier B.V. All rights reserved.

Does sex-ratio selection influence nest-site choice in a reptile with temperature-dependent sex determination?

PubMed

Mitchell, Timothy S; Maciel, Jessica A; Janzen, Fredric J

2013-12-07

Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness.

Does sex-ratio selection influence nest-site choice in a reptile with temperature-dependent sex determination?

PubMed Central

Mitchell, Timothy S.; Maciel, Jessica A.; Janzen, Fredric J.

2013-01-01

Evolutionary theory predicts that dioecious species should produce a balanced primary sex ratio maintained by frequency-dependent selection. Organisms with environmental sex determination, however, are vulnerable to maladaptive sex ratios, because environmental conditions vary spatio-temporally. For reptiles with temperature-dependent sex determination, nest-site choice is a behavioural maternal effect that could respond to sex-ratio selection, as mothers could adjust offspring sex ratios by choosing nest sites that will have particular thermal properties. This theoretical prediction has generated decades of empirical research, yet convincing evidence that sex-ratio selection is influencing nesting behaviours remains absent. Here, we provide the first experimental evidence from nature that sex-ratio selection, rather than only viability selection, is probably an important component of nest-site choice in a reptile with temperature-dependent sex determination. We compare painted turtle (Chrysemys picta) neonates from maternally selected nest sites with those from randomly selected nest sites, observing no substantive difference in hatching success or survival, but finding a profound difference in offspring sex ratio in the direction expected based on historical records. Additionally, we leverage long-term data to reconstruct our sex ratio results had the experiment been repeated in multiple years. As predicted by theory, our results suggest that sex-ratio selection has shaped nesting behaviour in ways likely to enhance maternal fitness. PMID:24266033

Use of complementary and alternative medicine by patients with arthritis.

PubMed

Unsal, Ayla; Gözüm, Sebahat

2010-04-01

The aims of this study were to determine the prevalence of complementary and alternative medicine use in patients with arthritis, the types of complementary and alternative medicine used, pertinent socio-demographic factors associated with complementary and alternative medicine use and its perceived efficacy. Arthritis is a major health issue, and the use of complementary and alternative medicine among patients with arthritis is common. This is a descriptive cross-sectional study. Data were obtained from 250 patients with arthritis at the physiotherapy and immunology clinics Atatürk University Hospital in eastern Turkey between May-July 2005 using a questionnaire developed specifically for this study. The instrument included questions on socio-demographic information, disease specifics and complementary and alternative medicine usage. Seventy-six per cent of participants reported use of at least one form of complementary and alternative medicine in the previous year. Complementary and alternative medicine users and non-users were not significantly different in most socio-demographic characteristics including age, gender, marital status and education level with the exception of economic status. We categorised treatment into six complementary and alternative medicine categories: 62.6% of patients used thermal therapies; 41.5% used oral herbal therapies; 40.5% used hot therapies; 32.6% used externally applied (skin) therapies; 28.4% used massage and 12.6% used cold therapies. All forms of complementary and alternative medicine except thermal and oral herbal therapies were perceived as very effective by more than half of study participants. Complementary and alternative medicine therapy is widely used by patients with arthritis and has perceived beneficial effects. It is important for nurses and other health care professionals to be knowledgeable about the use of complementary and alternative medicine therapies when providing care to patients with arthritis because of possible interactions with other treatments, delays in seeking care and the potential for poor quality products. It is also essential for health professionals to discuss treatment options with patients and to monitor treatment efficacy.

Use of algal fluorescence for determination of phytotoxicity of heavy metals and pesticides as environmental pollutants.

PubMed

Samson, G; Popovic, R

1988-12-01

The phytotoxicity of heavy metals and pesticides was studied by using the fluorescence induction from the alga Dunaliella tertiolecta. The complementary area calculated from the variable fluorescence induction was used as a direct parameter to estimate phytotoxicity. The value of this parameter was affected when algae were treated with different concentrations of mercury, copper, atrazine, DCMU, Dutox, and Soilgard. The toxic effect of these pollutants was estimated by monitoring the decrease in the complementary area, which reflects photosystem II photochemistry. Further, the authors have demonstrated the advantage of using the complementary area as a parameter of phytotoxicity over using variable fluorescence yield. The complementary area of algal fluorescence can be used as a simple and sensitive parameter in the estimation of the phytotoxicity of polluted water.

Identification of Novel Targets for Lung Cancer Therapy Using an Induced Pluripotent Stem Cell Model.

PubMed

Shukla, Vivek; Rao, Mahadev; Zhang, Hongen; Beers, Jeanette; Wangsa, Darawalee; Wangsa, Danny; Buishand, Floryne O; Wang, Yonghong; Yu, Zhiya; Stevenson, Holly; Reardon, Emily; McLoughlin, Kaitlin C; Kaufman, Andrew; Payabyab, Eden; Hong, Julie A; Zhang, Mary; Davis, Sean R; Edelman, Daniel C; Chen, Guokai; Miettinen, Markku; Restifo, Nicholas; Ried, Thomas; Meltzer, Paul S; Schrump, David S

2018-04-01

Despite extensive studies, the genetic and epigenetic mechanisms that mediate initiation and progression of lung cancers have not been fully elucidated. Previously, we have demonstrated that via complementary mechanisms, including DNA methylation, polycomb repressive complexes, and noncoding RNAs, cigarette smoke induces stem-like phenotypes that coincide with progression to malignancy in normal respiratory epithelia as well as enhanced growth and metastatic potential of lung cancer cells. To further investigate epigenetic mechanisms contributing to stemness/pluripotency in lung cancers and potentially identify novel therapeutic targets in these malignancies, induced pluripotent stem cells were generated from normal human small airway epithelial cells. Lung induced pluripotent stem cells were generated by lentiviral transduction of small airway epithelial cells of OSKM (Yamanaka) factors (octamer-binding transcription factor 4 [Oct4], sex-determining region Y box 2 [SOX2], Kruppel-like factor 4 [KLF4], and MYC proto-oncogene, bHLH transcription factor [MYC]). Western blot, real-time polymerase chain reaction, and chromatin immunoprecipitation sequencing analysis were performed. The lung induced pluripotent stem cells exhibited hallmarks of pluripotency, including morphology, surface antigen and stem cell gene expression, in vitro proliferation, and teratoma formation. In addition, lung induced pluripotent stem cells exhibited no chromosomal aberrations, complete silencing of reprogramming transgenes, genomic hypermethylation, upregulation of genes encoding components of polycomb repressive complex 2, hypermethylation of stem cell polycomb targets, and modulation of more than 15,000 other genes relative to parental small airway epithelial cells. Additional sex combs like-3 (ASXL3), encoding a polycomb repressive complex 2-associated protein not previously described in reprogrammed cells, was markedly upregulated in lung induced pluripotent stem cell as well as human small cell lung cancer lines and specimens. Overexpression of the additional sex combs like-3 gene correlated with increased genomic copy number in small cell lung cancer lines. Knock-down of the additional sex combs like-3 gene inhibited proliferation, clonogenicity, and teratoma formation by lung induced pluripotent stem cells and significantly diminished in vitro clonogenicity and growth of small cell lung cancer cells in vivo. Collectively, these studies highlight the potential utility of this lung induced pluripotent stem cell model for elucidating epigenetic mechanisms contributing to pulmonary carcinogenesis and suggest that additional sex combs like-3 is a novel target for small cell lung cancer therapy.

Dmrt1 is necessary for male sexual development in zebrafish

PubMed Central

Webster, Kaitlyn A.; Schach, Ursula; Ordaz, Angel; Steinfeld, Jocelyn S.; Draper, Bruce W.; Siegfried, Kellee R.

2018-01-01

The dmrt1 (doublesex and mab-3 related transcription factor 1) gene is a key regulator of sex determination and/or gonadal sex differentiation across metazoan animals. This is unusual given that sex determination genes are typically not well conserved. The mechanisms by which zebrafish sex is determined have remained elusive due to the lack of sex chromosomes and the complex polygenic nature of sex determination in domesticated strains. To investigate the role of dmrt1 in zebrafish sex determination and gonad development, we isolated mutations disrupting this gene. We found that the majority of dmrt1 mutant fish develop as fertile females suggesting a complete male-to-female sex reversal in mutant animals that would have otherwise developed as males. A small percentage of mutant animals became males, but were sterile and displayed testicular dysgenesis. Therefore zebrafish dmrt1 functions in male sex determination and testis development. Mutant males had aberrant gonadal development at the onset of gonadal sex-differentiation, displaying reduced oocyte apoptosis followed by development of intersex gonads and failed testis morphogenesis and spermatogenesis. By contrast, female ovaries developed normally. We found that Dmrt1 is necessary for normal transcriptional regulation of the amh (anti-Müllerian hormone) and foxl2 (forkhead box L2) genes, which are thought to be important for male or female sexual development respectively. Interestingly, we identified one dmrt1 mutant allele that cooperates with a linked segregation distorter locus to generate an apparent XY sex determination mechanism. We conclude that dmrt1 is dispensable for ovary development but necessary for testis development in zebrafish, and that dmrt1 promotes male development by transcriptionally regulating male and female genes as has been described in other animals. Furthermore, the strong sex-ratio bias caused by dmrt1 reduction-of-function points to potential mechanisms through which sex chromosomes may evolve. PMID:27940159

The nuclear hormone receptor SEX-1 is an X-chromosome signal that determines nematode sex.

PubMed

Carmi, I; Kopczynski, J B; Meyer, B J

1998-11-12

Organisms in many phyla determine sexual fate by distinguishing one X chromosome from two. Here we use the model organism Caenorhabditis elegans to dissect such an X-chromosome-counting mechanism in molecular detail. In this nematode, several genes on the X chromosome called X signal elements communicate X-chromosome dose by controlling the activity of the sex-determination gene xol-1. xol-1 specifies male (XO) fate when active and hermaphrodite (XX) fate when inactive. The only X signal element described so far represses xol-1 post-transcriptionally, but xol-1 is repressed in XX animals by transcriptional and post-transcriptional mechanisms. Here we identify a nuclear-hormone-receptor homologue, SEX-1, that regulates the transcription of xol-1. We show that sex-1 is vital to X-chromosome counting: changing sex-1 gene dose in XX or XO embryos causes sexual transformation and death from inadequate dosage compensation (the hermaphrodite-specific process that equalizes X-gene expression between the sexes). The SEX-1 protein acts directly on xol-1, associating with its promoter in vivo and repressing xol-1 transcription in XX embryos. Thus, xol-1 is the direct molecular target of the primary sex-determination signal, and the dose of a nuclear hormone receptor helps to communicate X-chromosome number to determine nematode sex.

Foot index: is it a tool for sex determination?

PubMed

Moudgil, Rohan; Kaur, Ramneet; Menezes, Ritesh G; Kanchan, Tanuj; Garg, Rakesh K

2008-05-01

Identification of an individual is of paramount importance in forensic investigations. The dimensions of the foot can be used for the determination of sex and stature of an individual in forensic investigations. No systematic studies are available on the determination of sex from foot measurements of North Indians. Therefore, foot index is derived to determine the sex of an individual in a single community of North India. The foot index for both genders is derived by dividing the foot breadth by foot length and multiplying it by hundred. In the present investigation, the foot index is found to be slightly higher in females in the right foot and males in the left foot. The study suggests that although foot length and foot breadth show significant sex differences, sex determination cannot be made conclusively from the foot index.

Sexual conflict resolved by invasion of a novel sex determiner in Lake Malawi cichlid fishes.

PubMed

Roberts, Reade B; Ser, Jennifer R; Kocher, Thomas D

2009-11-13

Sex determination mechanisms differ among animal species, but it is not clear how these differences evolve. New sex determiners may arise in response to sexual conflicts, which occur when traits benefit one sex but hinder the other. We identified the genetic basis for the orange-blotch (OB) color pattern, a trait under sexually antagonistic selection in the cichlid fish of Lake Malawi, East Africa. The OB phenotype is due to a cis-regulatory mutation in the Pax7 gene. OB provides benefits of camouflage to females but disrupts the species-specific male color patterns used for mate recognition. We suggest that the resulting sexual conflict over the OB allele has been resolved by selection for a novel female sex determination locus that has invaded populations with an ancestral male sex determination system.

Sex Determination, Sex Chromosomes, and Karyotype Evolution in Insects.

PubMed

Blackmon, Heath; Ross, Laura; Bachtrog, Doris

2017-01-01

Insects harbor a tremendous diversity of sex determining mechanisms both within and between groups. For example, in some orders such as Hymenoptera, all members are haplodiploid, whereas Diptera contain species with homomorphic as well as male and female heterogametic sex chromosome systems or paternal genome elimination. We have established a large database on karyotypes and sex chromosomes in insects, containing information on over 13000 species covering 29 orders of insects. This database constitutes a unique starting point to report phylogenetic patterns on the distribution of sex determination mechanisms, sex chromosomes, and karyotypes among insects and allows us to test general theories on the evolutionary dynamics of karyotypes, sex chromosomes, and sex determination systems in a comparative framework. Phylogenetic analysis reveals that male heterogamety is the ancestral mode of sex determination in insects, and transitions to female heterogamety are extremely rare. Many insect orders harbor species with complex sex chromosomes, and gains and losses of the sex-limited chromosome are frequent in some groups. Haplodiploidy originated several times within insects, and parthenogenesis is rare but evolves frequently. Providing a single source to electronically access data previously distributed among more than 500 articles and books will not only accelerate analyses of the assembled data, but also provide a unique resource to guide research on which taxa are likely to be informative to address specific questions, for example, for genome sequencing projects or large-scale comparative studies. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Prayer and blessings focused for healing is the most popular complementary intervention in a paediatric oncology unit in Greece.

PubMed

Pourtsidis, Apostolos; Doganis, Dimitrios; Baka, Margarita; Varvoutsi, Maria; Bouhoutsou, Despina; Xatzi, Panagiota; Kosmidis, Helen

2015-01-01

Increasing numbers of children with cancer are using complementary and alternative medicine (CAM) therapies. Our aim was to estimate the rate of use, the beliefs of users and non-users and factors related with the use of CAM among Greek families. A self-reported questionnaire was given to parents of 184 children with cancer. We assessed the rate of use, types of CAM therapies and factors potentially associated with the use of CAM. Based on the 110 questionnaires which were completed (59.8% of the families), 23 families (21%) had used at least one complementary treatment. The most common forms were: spiritual healing/prayer/blessings 18/23 (78%), art therapies 4, dietary supplements 3, massage 3, homeopathy 2, and herbals 2. The reasons given for use included: making the child stronger 17/23 (48%, hope of stopping the cancerous process 11/23 (49%), and coping with side effects 6/23 (26%). Among the reasons given by the parents for not using CAM therapies the most common (84%) was the effective conventional treatment and, therefore, there was no need for CAM use. Another 24% reported that were unaware of these "alternative" and "complementary" therapies and a further 7% had considered using them but finally they didn't. In bivariate analysis, the use of CAM was not associated either with age, sex, nationality, education or occupation of the parents at the time of the survey, or with diagnosis, mode of therapy or age of the child at diagnosis. The use of CAM therapies by Greek families for their children with cancer does not appear to be very popular, although the experiences of those who did use them were generally positive.

Divergent Evolutionary Trajectories of Two Young, Homomorphic, and Closely Related Sex Chromosome Systems

PubMed Central

Furman, Benjamin L S; Evans, Ben J

2018-01-01

Abstract There exists extraordinary variation among species in the degree and nature of sex chromosome divergence. However, much of our knowledge about sex chromosomes is based on comparisons between deeply diverged species with different ancestral sex chromosomes, making it difficult to establish how fast and why sex chromosomes acquire variable levels of divergence. To address this problem, we studied sex chromosome evolution in two species of African clawed frog (Xenopus), both of whom acquired novel systems for sex determination from a recent common ancestor, and both of whom have female (ZW/ZZ) heterogamy. Derived sex chromosomes of one species, X. laevis, have a small region of suppressed recombination that surrounds the sex determining locus, and have remained this way for millions of years. In the other species, X. borealis, a younger sex chromosome system exists on a different pair of chromosomes, but the region of suppressed recombination surrounding an unidentified sex determining gene is vast, spanning almost half of the sex chromosomes. Differences between these sex chromosome systems are also apparent in the extent of nucleotide divergence between the sex chromosomes carried by females. Our analyses also indicate that in autosomes of both of these species, recombination during oogenesis occurs more frequently and in different genomic locations than during spermatogenesis. These results demonstrate that new sex chromosomes can assume radically different evolutionary trajectories, with far-reaching genomic consequences. They also suggest that in some instances the origin of new triggers for sex determination may be coupled with rapid evolution sex chromosomes, including recombination suppression of large genomic regions. PMID:29608717

ZWY Sex Determination in Xenopus tropicalis

EPA Science Inventory

Most vertebrate species with described genetic sex determination are either male (XY) or female (ZW) heterogametic. To date, studies with Xenopus species indicate that members of this genus operate under a ZW sex determination system. We used two different approaches and demonst...

Protein kinase C is involved with upstream signaling of methyl farnesoate for photoperiod-dependent sex determination in the water flea Daphnia pulex.

PubMed

Toyota, Kenji; Sato, Tomomi; Tatarazako, Norihisa; Iguchi, Taisen

2017-02-15

Sex determination of Daphnia pulex is decided by environmental conditions. We established a suitable experimental system for this study using D. pulex WTN6 strain, in which the sex of the offspring can be controlled by photoperiod. Long-day conditions induced females and short-day conditions induced males. Using this system, we previously found that methy farnesoate (MF), which is a putative innate juvenile hormone molecule in daphnids, is necessary for male sex determination and that protein kinase C (PKC) is a candidate factor of male sex determiner. In this study, we demonstrated that a PKC inhibitor [bisindolylmaleimide IV (BIM)] application strongly suppressed male offspring induction in the short-day condition. Moreover, co-treatment of BIM with MF revealed that PKC signaling acts upstream of MF signaling for male sex determination. This is the first experimental evidence that PKC is involved in the male sex determination process associated with methyl farnesoate signaling in daphnid species. © 2017. Published by The Company of Biologists Ltd.

Efficacy of Sex Determination from Human Dental Pulp Tissue and its Reliability as a Tool in Forensic Dentistry

PubMed Central

Khanna, Kaveri Surya

2015-01-01

Background: Sex determination is one of the primary steps in forensics. Barr body can be used as a histological method for identification of sex as it is found to be specific to female somatic cells and rare in male cells. To demarcate human dental pulp as an important identification tool of sex in forensic odontology (FO) and to evaluate the time period till which sex can be determined from pulp tissue using three stains H and E, Feulgen, and acridine - orange under fluorescence so as. Materials and Methods: 90 pulp samples (45 males and 45 females) were subjected to Barr body analysis for determination of sex using light and fluorescent microscopy. Results: Barr body was found to be positive for female samples and negative or rare in the male sample (<3%). Conclusion: Barr body from human dental pulp tissue can be used as a successful determinant of sex identification in FO. PMID:26668474

Origin and transition of sex determination mechanisms in a gynogenetic hexaploid fish.

PubMed

Li, Xi-Yin; Liu, Xiao-Li; Zhu, Yao-Jun; Zhang, Jun; Ding, Miao; Wang, Ming-Tao; Wang, Zhong-Wei; Li, Zhi; Zhang, Xiao-Juan; Zhou, Li; Gui, Jian-Fang

2018-02-02

Most vertebrates reproduce sexually, and plastic sex determination mechanisms including genotypic sex determination (GSD) and environmental sex determination (ESD) have been extensively revealed. However, why sex determination mechanisms evolve diversely and how they correlate with diverse reproduction strategies remain largely unclear. Here, we utilize the superiority of a hexaploid gibel carp (Carassius gibelio) that is able to reproduce by unisexual gynogenesis and contains a rare but diverse proportion of males to investigate these puzzles. A total of 2248 hexaploid specimens were collected from 34 geographic wild populations throughout mainland China, in which 24 populations were revealed to contain 186 males with various incidences ranging from 1.2 to 26.5%. Subsequently, the proportion of temperature-dependent sex determination (TSD) was revealed to be positively correlated to average annual temperature in wild populations, and male incidence in lab gynogenetic progenies was demonstrated to increase with the increasing of larval rearing temperature. Meanwhile, extra microchromosomes were confirmed to play genotypic male determination role as previously reported. Thereby, GSD and TSD were found to coexist in gibel carp, and the proportions of GSD were observed to be much higher than that of TSD in sympatric wild populations. Our findings uncover a potential new mechanism in the evolution of sex determination system in polyploid vertebrates with unisexual gynogenesis ability, and also reveal a possible association of sex determination mechanism transition between TSD and GSD and reproduction mode transition between unisexual gynogenesis and bisexual reproduction.

Use of B-mode ultrasonography for fetal sex determination in dogs.

PubMed

Gil, E M U; Garcia, D A A; Giannico, A T; Froes, T R

2015-10-01

Ultrasonographic determination of fetal sex in dogs has not previously been reported. The aim of this study was to describe a method for determination of intrauterine fetal sex using ultrasound. A cohort study was conducted in pregnant bitches to perform ultrasound examination of the fetal genitalia between the eighth and ninth week of gestation. Fetal sex was determined in utero by consensus agreement of two sonographers. Eighteen pregnant bitches were included in this study, and a total of 39 fetuses were evaluated. The accuracy of ultrasonography to determine the sex with a 95% confidence interval was 62.24% to female fetuses and 65.48% to male fetuses. The sonographic accuracy in determining fetal sex can be achieved at 100% when there are up to two fetuses in the litter; however, the accuracy of the technique reduces (66.7%) when more than three fetuses are present. This study describes the sonographic appearance of the external genitalia in canine fetuses in utero associated with a specific position of the fetus and reports that sex determination is possible between 55 and 58 days of gestation. Copyright © 2015 Elsevier Inc. All rights reserved.

Elucidation of the transcription network governing mammalian sex determination by exploiting strain-specific susceptibility to sex reversal

PubMed Central

Munger, Steven C.; Aylor, David L.; Syed, Haider Ali; Magwene, Paul M.; Threadgill, David W.; Capel, Blanche

2009-01-01

Despite the identification of some key genes that regulate sex determination, most cases of disorders of sexual development remain unexplained. Evidence suggests that the sexual fate decision in the developing gonad depends on a complex network of interacting factors that converge on a critical threshold. To elucidate the transcriptional network underlying sex determination, we took the first expression quantitative trait loci (eQTL) approach in a developing organ. We identified reproducible differences in the transcriptome of the embryonic day 11.5 (E11.5) XY gonad between C57BL/6J (B6) and 129S1/SvImJ (129S1), indicating that the reported sensitivity of B6 to sex reversal is consistent with a higher expression of a female-like transcriptome in B6. Gene expression is highly variable in F2 XY gonads from B6 and 129S1 intercrosses, yet strong correlations emerged. We estimated the F2 coexpression network and predicted roles for genes of unknown function based on their connectivity and position within the network. A genetic analysis of the F2 population detected autosomal regions that control the expression of many sex-related genes, including Sry (sex-determining region of the Y chromosome) and Sox9 (Sry-box containing gene 9), the key regulators of male sex determination. Our results reveal the complex transcription architecture underlying sex determination, and provide a mechanism by which individuals may be sensitized for sex reversal. PMID:19884258

Demographic and genetic consequences of disturbed sex determination.

PubMed

Wedekind, Claus

2017-09-19

During sex determination, genetic and/or environmental factors determine the cascade of processes of gonad development. Many organisms, therefore, have a developmental window in which their sex determination can be sensitive to, for example, unusual temperatures or chemical pollutants. Disturbed environments can distort population sex ratios and may even cause sex reversal in species with genetic sex determination. The resulting genotype-phenotype mismatches can have long-lasting effects on population demography and genetics. I review the theoretical and empirical work in this context and explore in a simple population model the role of the fitness v yy of chromosomally aberrant YY genotypes that are a consequence of environmentally induced feminization. Low v yy is mostly beneficial for population growth. During feminization, low v yy reduces the proportion of genetic males and hence accelerates population growth, especially at low rates of feminization and at high fitness costs of the feminization itself (i.e. when feminization would otherwise not affect population dynamics much). When sex reversal ceases, low v yy mitigates the negative effects of feminization and can even prevent population extinction. Little is known about v yy in natural populations. The available models now need to be parametrized in order to better predict the long-term consequences of disturbed sex determination.This article is part of the themed issue 'Adult sex ratios and reproductive decisions: a critical re-examination of sex differences in human and animal societies'. © 2017 The Author(s).

Complementary and alternative medicine use in Iranian patients with diabetes mellitus.

PubMed

Hashempur, Mohammad Hashem; Heydari, Mojtaba; Mosavat, Seyed Hamdollah; Heydari, Seyyed Taghi; Shams, Mesbah

2015-09-01

There is increasing interest in complementary and alternative medicine generally, and especially by those affected by chronic diseases, such as diabetes mellitus. We aimed to determine the prevalence and pattern of complementary and alternative medicine use among patients suffering from diabetes mellitus in Shiraz, southern Iran. Another objective was to explore associated factors for use of complementary and alternative medicine among patients with diabetes mellitus. A 19-item semi-structured questionnaire (open- and close-ended) was administered to 239 patients with diabetes mellitus in this cross-sectional study. It was carried out in two outpatient diabetes clinics affiliated with the Shiraz University of Medical Sciences, Shiraz, Iran. One hundred and eighty patients (75.3%) used at least one type of complementary and alternative medicine in the last year prior to the interview. Patients with diabetes mellitus who were living in a large family (≥5 members), not taking insulin, and believed that complementary and alternative medicine have synergistic effects with conventional medicine, were independently and significantly (P values: 0.02, 0.04, and 0.01, respectively) more likely to use complementary and alternative medicine. Most of the users (97.7%) reported use of herbal preparations, and 89.4% of users did not change their medication, neither in medication schedule nor its dosage. The use of complementary and alternative medicine, especially herbal remedies, is popular among diabetes patients in Shiraz, Iran. This use is associated with patients' family size, type of conventional medications and their view about concomitant use of complementary and conventional medicine.

Social Origins of Developmental Risk for Mental and Physical Illness.

PubMed

Cameron, Judy L; Eagleson, Kathie L; Fox, Nathan A; Hensch, Takao K; Levitt, Pat

2017-11-08

Adversity in early childhood exerts an enduring impact on mental and physical health, academic achievement, lifetime productivity, and the probability of interfacing with the criminal justice system. More science is needed to understand how the brain is affected by early life stress (ELS), which produces excessive activation of stress response systems broadly throughout the child's body (toxic stress). Our research examines the importance of sex, timing and type of stress exposure, and critical periods for intervention in various brain systems across species. Neglect (the absence of sensitive and responsive caregiving) or disrupted interaction with offspring induces robust, lasting consequences in mice, monkeys, and humans. Complementary assessment of internalizing disorders and brain imaging in children suggests that early adversity can interfere with white matter development in key brain regions, which may increase risk for emotional difficulties in the long term. Neural circuits that are most plastic during ELS exposure in monkeys sustain the greatest change in gene expression, offering a mechanism whereby stress timing might lead to markedly different long-term behaviors. Rodent models reveal that disrupted maternal-infant interactions yield metabolic and behavioral outcomes often differing by sex. Moreover, ELS may further accelerate or delay critical periods of development, which reflect GABA circuit maturation, BDNF, and circadian Clock genes. Such factors are associated with several mental disorders and may contribute to a premature closure of plastic windows for intervention following ELS. Together, complementary cross-species studies are elucidating principles of adaptation to adversity in early childhood with molecular, cellular, and whole organism resolution. Copyright © 2017 the authors 0270-6474/17/3710783-09$15.00/0.

Determinants of inadequate complementary feeding practices among children aged 6-23 months in Ghana.

PubMed

Issaka, Abukari I; Agho, Kingsley E; Burns, Penelope; Page, Andrew; Dibley, Michael J

2015-03-01

To explore complementary feeding practices and identify potential risk factors associated with inadequate complementary feeding practices in Ghana by using the newly developed WHO infant feeding indicators and data from the nationally representative 2008 Ghana Demographic and Health Survey. The source of data for the analysis was the 2008 Ghana Demographic and Health Survey. Analysis of the factors associated with inadequate complementary feeding, using individual-, household- and community-level determinants, was done by performing multiple logistic regression modelling. Ghana. Children (n 822) aged 6-23 months. The prevalence of the introduction of solid, semi-solid or soft foods among infants aged 6-8 months was 72.6 % (95 % CI 64.6 %, 79.3 %). The proportion of children aged 6-23 months who met the minimum meal frequency and dietary diversity for breast-fed and non-breast-fed children was 46.0 % (95 % CI 42.3 %, 49.9 %) and 51.4 % (95 % CI 47.4 %, 55.3 %) respectively and the prevalence of minimum acceptable diet for breast-fed children was 29.9 % (95 % CI 26.1 %, 34.1 %). Multivariate analysis revealed that children from the other administrative regions were less likely to meet minimum dietary diversity, meal frequency and acceptable diet than those from the Volta region. Household poverty, children whose mothers perceived their size to be smaller than average and children who were delivered at home were significantly less likely to meet the minimum dietary diversity requirement; and children whose mothers did not have any postnatal check-ups were significantly less likely to meet the requirement for minimum acceptable diet. Complementary feeding was significantly lower in infants from illiterate mothers (adjusted OR=3.55; 95 % CI 1.05, 12.02). The prevalence of complementary feeding among children in Ghana is still below the WHO-recommended standard of 90 % coverage. Non-attendance of postnatal check-up by mothers, cultural beliefs and habits, household poverty, home delivery of babies and non-Christian mothers were the most important risk factors for inadequate complementary feeding practices. Therefore, nutrition educational interventions to improve complementary feeding practices should target these factors in order to achieve the fourth Millennium Development Goal.

Single locus sex determination and female heterogamety in the basket willow (Salix viminalis L.).

PubMed

Pucholt, P; Rönnberg-Wästljung, A-C; Berlin, S

2015-06-01

Most eukaryotes reproduce sexually and a wealth of different sex determination mechanisms have evolved in this lineage. Dioecy or separate sexes are rare among flowering plants but have repeatedly evolved from hermaphroditic ancestors possibly involving male or female sterility mutations. Willows (Salix spp.) and poplars (Populus spp.) are predominantly dioecious and are members of the Salicaceae family. All studied poplars have sex determination loci on chromosome XIX, however, the position differs among species and both male and female heterogametic system exists. In contrast to the situation in poplars, knowledge of sex determination mechanisms in willows is sparse. In the present study, we have for the first time positioned the sex determination locus on chromosome XV in S. viminalis using quantitative trait locus mapping. All female offspring carried a maternally inherited haplotype, suggesting a system of female heterogamety or ZW. We used a comparative mapping approach and compared the positions of the markers between the S. viminalis linkage map and the physical maps of S. purpurea, S. suchowensis and P. trichocarpa. As we found no evidence for chromosomal rearrangements between chromosome XV and XIX between S. viminalis and P. trichocarpa, it shows that the sex determination loci in the willow and the poplar most likely do not share a common origin and has thus evolved separately. This demonstrates that sex determination mechanisms in the Salicaceae family have a high turnover rate and as such it is excellent for studies of evolutionary processes involved in sex chromosome turnover.

Single locus sex determination and female heterogamety in the basket willow (Salix viminalis L.)

PubMed Central

Pucholt, P; Rönnberg-Wästljung, A-C; Berlin, S

2015-01-01

Most eukaryotes reproduce sexually and a wealth of different sex determination mechanisms have evolved in this lineage. Dioecy or separate sexes are rare among flowering plants but have repeatedly evolved from hermaphroditic ancestors possibly involving male or female sterility mutations. Willows (Salix spp.) and poplars (Populus spp.) are predominantly dioecious and are members of the Salicaceae family. All studied poplars have sex determination loci on chromosome XIX, however, the position differs among species and both male and female heterogametic system exists. In contrast to the situation in poplars, knowledge of sex determination mechanisms in willows is sparse. In the present study, we have for the first time positioned the sex determination locus on chromosome XV in S. viminalis using quantitative trait locus mapping. All female offspring carried a maternally inherited haplotype, suggesting a system of female heterogamety or ZW. We used a comparative mapping approach and compared the positions of the markers between the S. viminalis linkage map and the physical maps of S. purpurea, S. suchowensis and P. trichocarpa. As we found no evidence for chromosomal rearrangements between chromosome XV and XIX between S. viminalis and P. trichocarpa, it shows that the sex determination loci in the willow and the poplar most likely do not share a common origin and has thus evolved separately. This demonstrates that sex determination mechanisms in the Salicaceae family have a high turnover rate and as such it is excellent for studies of evolutionary processes involved in sex chromosome turnover. PMID:25649501

Abortion and sex determination: conflicting messages in information materials in a District of Rajasthan, India.

PubMed

Nidadavolu, Vijaya; Bracken, Hillary

2006-05-01

Public information campaigns are an integral component of reproductive health programmes, including on abortion. In India, where sex selective abortion is increasing, public information is being disseminated on the illegality of sex determination. This paper presents findings from a study undertaken in 2003 in one district in Rajasthan to analyse the content of information materials on abortion and sex determination and people's perceptions of them. Most of the informational material about abortion was produced by one abortion service provider, but none by the public or private sector. The public sector had produced materials on the illegality of sex determination, some of which failed to distinguish between sex selection and other reasons for abortion. In the absence of knowledge of the legal status of abortion, the negative messages and strong language of these materials may have contributed to the perception that abortion is illegal in India. Future materials should address abortion and sex determination, including the legal status of abortion, availability of providers and social norms that shape decision-making. Married and unmarried women should be addressed and the participation of family members acknowledged, while supporting independent decisions by women. Sex determination should also be addressed, and the conditions under which a woman can and cannot seek an abortion clarified, using media and materials accessible to low-literate audiences. Based on what we learned in this research, a pictorial booklet and educator's manual were produced, covering both abortion and sex determination, and are being distributed in India.

Transcriptome display during tilapia sex determination and differentiation as revealed by RNA-Seq analysis.

PubMed

Tao, Wenjing; Chen, Jinlin; Tan, Dejie; Yang, Jing; Sun, Lina; Wei, Jing; Conte, Matthew A; Kocher, Thomas D; Wang, Deshou

2018-05-15

The factors determining sex in teleosts are diverse. Great efforts have been made to characterize the underlying genetic network in various species. However, only seven master sex-determining genes have been identified in teleosts. While the function of a few genes involved in sex determination and differentiation has been studied, we are far from fully understanding how genes interact to coordinate in this process. To enable systematic insights into fish sexual differentiation, we generated a dynamic co-expression network from tilapia gonadal transcriptomes at 5, 20, 30, 40, 90, and 180 dah (days after hatching), plus 45 and 90 dat (days after treatment) and linked gene expression profiles to both development and sexual differentiation. Transcriptomic profiles of female and male gonads at 5 and 20 dah exhibited high similarities except for a small number of genes that were involved in sex determination, while drastic changes were observed from 90 to 180 dah, with a group of differently expressed genes which were involved in gonadal differentiation and gametogenesis. Weighted gene correlation network analysis identified changes in the expression of Borealin, Gtsf1, tesk1, Zar1, Cdn15, and Rpl that were correlated with the expression of genes previously known to be involved in sex differentiation, such as Foxl2, Cyp19a1a, Gsdf, Dmrt1, and Amh. Global gonadal gene expression kinetics during sex determination and differentiation have been extensively profiled in tilapia. These findings provide insights into the genetic framework underlying sex determination and sexual differentiation, and expand our current understanding of developmental pathways during teleost sex determination.

Sex Determination from Fragmented and Degenerated DNA by Amplified Product-Length Polymorphism Bidirectional SNP Analysis of Amelogenin and SRY Genes.

PubMed

Masuyama, Kotoka; Shojo, Hideki; Nakanishi, Hiroaki; Inokuchi, Shota; Adachi, Noboru

2017-01-01

Sex determination is important in archeology and anthropology for the study of past societies, cultures, and human activities. Sex determination is also one of the most important components of individual identification in criminal investigations. We developed a new method of sex determination by detecting a single-nucleotide polymorphism in the amelogenin gene using amplified product-length polymorphisms in combination with sex-determining region Y analysis. We particularly focused on the most common types of postmortem DNA damage in ancient and forensic samples: fragmentation and nucleotide modification resulting from deamination. Amplicon size was designed to be less than 60 bp to make the method more useful for analyzing degraded DNA samples. All DNA samples collected from eight Japanese individuals (four male, four female) were evaluated correctly using our method. The detection limit for accurate sex determination was determined to be 20 pg of DNA. We compared our new method with commercial short tandem repeat analysis kits using DNA samples artificially fragmented by ultraviolet irradiation. Our novel method was the most robust for highly fragmented DNA samples. To deal with allelic dropout resulting from deamination, we adopted "bidirectional analysis," which analyzed samples from both sense and antisense strands. This new method was applied to 14 Jomon individuals (3500-year-old bone samples) whose sex had been identified morphologically. We could correctly identify the sex of 11 out of 14 individuals. These results show that our method is reliable for the sex determination of highly degenerated samples.

Sex Determination from Fragmented and Degenerated DNA by Amplified Product-Length Polymorphism Bidirectional SNP Analysis of Amelogenin and SRY Genes

PubMed Central

Masuyama, Kotoka; Shojo, Hideki; Nakanishi, Hiroaki; Inokuchi, Shota; Adachi, Noboru

2017-01-01

Sex determination is important in archeology and anthropology for the study of past societies, cultures, and human activities. Sex determination is also one of the most important components of individual identification in criminal investigations. We developed a new method of sex determination by detecting a single-nucleotide polymorphism in the amelogenin gene using amplified product-length polymorphisms in combination with sex-determining region Y analysis. We particularly focused on the most common types of postmortem DNA damage in ancient and forensic samples: fragmentation and nucleotide modification resulting from deamination. Amplicon size was designed to be less than 60 bp to make the method more useful for analyzing degraded DNA samples. All DNA samples collected from eight Japanese individuals (four male, four female) were evaluated correctly using our method. The detection limit for accurate sex determination was determined to be 20 pg of DNA. We compared our new method with commercial short tandem repeat analysis kits using DNA samples artificially fragmented by ultraviolet irradiation. Our novel method was the most robust for highly fragmented DNA samples. To deal with allelic dropout resulting from deamination, we adopted “bidirectional analysis,” which analyzed samples from both sense and antisense strands. This new method was applied to 14 Jomon individuals (3500-year-old bone samples) whose sex had been identified morphologically. We could correctly identify the sex of 11 out of 14 individuals. These results show that our method is reliable for the sex determination of highly degenerated samples. PMID:28052096

Developmental outcomes among 18-month-old Malawians after a year of complementary feeding with lipid-based nutrient supplements or corn-soy flour

USDA-ARS?s Scientific Manuscript database

The major aim of this trial was to compare the development of 18-month-old infants who received complementary feeding for 1 year with either lipid-based nutrient supplements or micronutrient-fortified corn-soy porridge. Our secondary aim was to determine the socio-economic factors associated with de...

Prevalence and Predictors of Complementary and Alternative Medicine (CAM) Use among Ivy League College Students: Implications for Student Health Services

ERIC Educational Resources Information Center

Versnik Nowak, Amy L.; DeGise, Joe; Daugherty, Amanda; O'Keefe, Richard; Seward, Samuel, Jr.; Setty, Suma; Tang, Fanny

2015-01-01

Objective: Determine prevalence and types of complementary and alternative medicine (CAM) therapies used and test the significance of demographics and social cognitive constructs as predictors of CAM use in a college sample. Secondary purpose was to guide the integration of CAM therapies into college health services. Participants: Random,…

Tree of Sex: A database of sexual systems

PubMed Central

Ashman, Tia-Lynn; Bachtrog, Doris; Blackmon, Heath; Goldberg, Emma E; Hahn, Matthew W; Kirkpatrick, Mark; Kitano, Jun; Mank, Judith E; Mayrose, Itay; Ming, Ray; Otto, Sarah P; Peichel, Catherine L; Pennell, Matthew W; Perrin, Nicolas; Ross, Laura; Valenzuela, Nicole; Vamosi, Jana C

2014-01-01

The vast majority of eukaryotic organisms reproduce sexually, yet the nature of the sexual system and the mechanism of sex determination often vary remarkably, even among closely related species. Some species of animals and plants change sex across their lifespan, some contain hermaphrodites as well as males and females, some determine sex with highly differentiated chromosomes, while others determine sex according to their environment. Testing evolutionary hypotheses regarding the causes and consequences of this diversity requires interspecific data placed in a phylogenetic context. Such comparative studies have been hampered by the lack of accessible data listing sexual systems and sex determination mechanisms across the eukaryotic tree of life. Here, we describe a database developed to facilitate access to sexual system and sex chromosome information, with data on sexual systems from 11,038 plant, 705 fish, 173 amphibian, 593 non-avian reptilian, 195 avian, 479 mammalian, and 11,556 invertebrate species. PMID:25977773

Tree of Sex: a database of sexual systems.

PubMed

2014-01-01

The vast majority of eukaryotic organisms reproduce sexually, yet the nature of the sexual system and the mechanism of sex determination often vary remarkably, even among closely related species. Some species of animals and plants change sex across their lifespan, some contain hermaphrodites as well as males and females, some determine sex with highly differentiated chromosomes, while others determine sex according to their environment. Testing evolutionary hypotheses regarding the causes and consequences of this diversity requires interspecific data placed in a phylogenetic context. Such comparative studies have been hampered by the lack of accessible data listing sexual systems and sex determination mechanisms across the eukaryotic tree of life. Here, we describe a database developed to facilitate access to sexual system and sex chromosome information, with data on sexual systems from 11,038 plant, 705 fish, 173 amphibian, 593 non-avian reptilian, 195 avian, 479 mammalian, and 11,556 invertebrate species.

Awareness and Attitudes Regarding Prenatal Sex Determination, Pre-Conception and Pre-Natal Diagnostic Techniques Act (PCPNDTA) among Pregnant Women in Southern India

PubMed Central

Kumar, Nithin; Unnikrishnan, Bhaskaran; Kanchan, Tanuj; Thapar, Rekha; Mithra, Prasanna; Kulkarni, Vaman; Holla, Ramesh

2014-01-01

Objectives: The present study was conducted to assess the awareness and attitude regarding prenatal sex determination and Pre-conception and Pre-natal Diagnostic techniques Act among pregnant women. Materials and Methods: A cross sectional study was carried at tertiary care teaching hospitals of Kasturba Medical College in Mangalore, India among 132 pregnant women. Data was collected using a pre-tested semi-structured questionnaire and was analysed using Statistical Package for Social Sciences(SPSS) version 11.5 and results were expressed in percentages. Results: The study included 132 participants and the mean age of study subjects was around 27 y. Majority of the study subjects (91.7%) knew that prenatal sex determination was possible. Three fourth (74.4%) of the participants prenatal sex determination was a punishable offence. One of the participants was ready to terminate pregnancy if sex of the fetus was revealed to be female before second trimester. Majority of participants (67.4%) were willing to educate people about PCPNDT act and motivate them against sex determination and sex selective abortions. Conclusion: Our study showed that higher proportion of participants knew about the prenatal sex determination and it was a punishable offence, still majority of them preferred to know the sex of unborn child which shows the need to implement the act effectively. PMID:25478372

Sex determination based on a thoracic vertebra and ribs evaluation using clinical chest radiography.

PubMed

Tsubaki, Shun; Morishita, Junji; Usumoto, Yosuke; Sakaguchi, Kyoko; Matsunobu, Yusuke; Kawazoe, Yusuke; Okumura, Miki; Ikeda, Noriaki

2017-07-01

Our aim was to investigate whether sex can be determined from a combination of geometric features obtained from the 10th thoracic vertebra, 6th rib, and 7th rib. Six hundred chest radiographs (300 males and 300 females) were randomly selected to include patients of six age groups (20s, 30s, 40s, 50s, 60s, and 70s). Each group included 100 images (50 males and 50 females). A total of 14 features, including 7 lengths, 5 indices for the vertebra, and 2 types of widths for ribs, were utilized and analyzed for sex determination. Dominant features contributing to sex determination were selected by stepwise discriminant analysis after checking the variance inflation factors for multicollinearity. The accuracy of sex determination using a combination of the vertebra and ribs was evaluated from the selected features by the stepwise discriminant analysis. The accuracies in each age group were also evaluated in this study. The accuracy of sex determination based on a combination of features of the vertebra and ribs was 88.8% (533/600). This performance was superior to that of the vertebra or ribs only. Moreover, sex determination of subjects in their 20s demonstrated the highest accuracy (96.0%, 96/100). The features selected in the stepwise discriminant analysis included some features in both the vertebra and ribs. These results indicate the usefulness of combined information obtained from the vertebra and ribs for sex determination. We conclude that a combination of geometric characteristics obtained from the vertebra and ribs could be useful for determining sex. Copyright © 2017 Elsevier B.V. All rights reserved.

Coexistence of Y, W, and Z sex chromosomes in Xenopus tropicalis

PubMed Central

Roco, Álvaro S.; Olmstead, Allen W.; Degitz, Sigmund J.; Amano, Tosikazu; Zimmerman, Lyle B.; Bullejos, Mónica

2015-01-01

Homomorphic sex chromosomes and rapid turnover of sex-determining genes can complicate establishing the sex chromosome system operating in a given species. This difficulty exists in Xenopus tropicalis, an anuran quickly becoming a relevant model for genetic, genomic, biochemical, and ecotoxicological research. Despite the recent interest attracted by this species, little is known about its sex chromosome system. Direct evidence that females are the heterogametic sex, as in the related species Xenopus laevis, has yet to be presented. Furthermore, X. laevis’ sex-determining gene, DM-W, does not exist in X. tropicalis, and the sex chromosomes in the two species are not homologous. Here we identify X. tropicalis’ sex chromosome system by integrating data from (i) breeding sex-reversed individuals, (ii) gynogenesis, (iii) triploids, and (iv) crosses among several strains. Our results indicate that at least three different types of sex chromosomes exist: Y, W, and Z, observed in YZ, YW, and ZZ males and in ZW and WW females. Because some combinations of parental sex chromosomes produce unisex offspring and other distorted sex ratios, understanding the sex-determination systems in X. tropicalis is critical for developing this flexible animal model for genetics and ecotoxicology. PMID:26216983

Determinants of inappropriate timing of introducing solid, semi-solid or soft food to infants in Pakistan: secondary data analysis of Demographic and Health Survey 2006-2007.

PubMed

Hazir, Tabish; Senarath, Upul; Agho, Kingsley; Akram, Dure-Samin; Kazmi, Narjis; Abbasi, Saleem; Dibley, Michael J

2012-01-01

Inappropriate timing of introducing complementary food deprives the infant of optimum nutrition, leading to undernutrition, and increased mortality and morbidity. The aim of this analysis was to identify determinants of inappropriate timing of introduction of solid, semi-solid and soft foods in Pakistan. Data on 941 infants 3.00 to 8.99 months were obtained from the Pakistan Demographic and Health Survey 2006-2007. The prevalence of introduction of foods among infants aged 3.00-5.99 months and 6.00-8.99 months was examined against a set of individual, household and community level variables using univariate analysis. Adjusted odds ratio (AOR) for early introduction in age 3.00-5.99 months and non-introduction in 6.00-8.99 months of age were calculated using backward stepwise logistic regression models. The prevalence of early introduction of complementary foods among 3.00- to 5.99-month-old and timely introduction among 6.00- to 8.99-month-old infants were 10.6% and 39.2%, respectively. Multivariate analyses revealed that mothers who had four or more antenatal clinic visits (AOR=2.68) and who lived in the provinces of Sindh (AOR=2.89) and Baluchistan (AOR=6.75) were more likely to introduce complementary foods early. Mothers from middle-level households (AOR=7.82), poorer households (AOR=4.84) and poorest households (AOR=5.72) were significantly more likely to delay introduction of complementary foods. In conclusion more than half (60.8%) of Pakistani infants do not receive complementary foods at recommended time. Public health interventions to improve the timing of introduction of complementary food are needed at national level with special focus on high risk groups. © 2011 Blackwell Publishing Ltd.

Infant Gut Microbiota Development Is Driven by Transition to Family Foods Independent of Maternal Obesity.

PubMed

Laursen, Martin Frederik; Andersen, Louise B B; Michaelsen, Kim F; Mølgaard, Christian; Trolle, Ellen; Bahl, Martin Iain; Licht, Tine Rask

2016-01-01

The first years of life are paramount in establishing our endogenous gut microbiota, which is strongly affected by diet and has repeatedly been linked with obesity. However, very few studies have addressed the influence of maternal obesity on infant gut microbiota, which may occur either through vertically transmitted microbes or through the dietary habits of the family. Additionally, very little is known about the effect of diet during the complementary feeding period, which is potentially important for gut microbiota development. Here, the gut microbiotas of two different cohorts of infants, born either of a random sample of healthy mothers (n = 114), or of obese mothers (n = 113), were profiled by 16S rRNA amplicon sequencing. Gut microbiota data were compared to breastfeeding patterns and detailed individual dietary recordings to assess effects of the complementary diet. We found that maternal obesity did not influence microbial diversity or specific taxon abundances during the complementary feeding period. Across cohorts, breastfeeding duration and composition of the complementary diet were found to be the major determinants of gut microbiota development. In both cohorts, gut microbial composition and alpha diversity were thus strongly affected by introduction of family foods with high protein and fiber contents. Specifically, intake of meats, cheeses, and Danish rye bread, rich in protein and fiber, were associated with increased alpha diversity. Our results reveal that the transition from early infant feeding to family foods is a major determinant for gut microbiota development. IMPORTANCE The potential influence of maternal obesity on infant gut microbiota may occur either through vertically transmitted microbes or through the dietary habits of the family. Recent studies have suggested that the heritability of obesity may partly be caused by the transmission of "obesogenic" gut microbes. However, the findings presented here suggest that maternal obesity per se does not affect the overall composition of the gut microbiota and its development after introduction of complementary foods. Rather, progression in complementary feeding is found to be the major determinant for gut microbiota establishment. Expanding our understanding of the influence of complementary diet on the development and establishment of the gut microbiota will provide us with the knowledge to tailor a beneficial progression of our intestinal microbial community.

Infant Gut Microbiota Development Is Driven by Transition to Family Foods Independent of Maternal Obesity

PubMed Central

Laursen, Martin Frederik; Andersen, Louise B. B.; Michaelsen, Kim F.; Mølgaard, Christian; Trolle, Ellen; Bahl, Martin Iain

2016-01-01

ABSTRACT The first years of life are paramount in establishing our endogenous gut microbiota, which is strongly affected by diet and has repeatedly been linked with obesity. However, very few studies have addressed the influence of maternal obesity on infant gut microbiota, which may occur either through vertically transmitted microbes or through the dietary habits of the family. Additionally, very little is known about the effect of diet during the complementary feeding period, which is potentially important for gut microbiota development. Here, the gut microbiotas of two different cohorts of infants, born either of a random sample of healthy mothers (n = 114), or of obese mothers (n = 113), were profiled by 16S rRNA amplicon sequencing. Gut microbiota data were compared to breastfeeding patterns and detailed individual dietary recordings to assess effects of the complementary diet. We found that maternal obesity did not influence microbial diversity or specific taxon abundances during the complementary feeding period. Across cohorts, breastfeeding duration and composition of the complementary diet were found to be the major determinants of gut microbiota development. In both cohorts, gut microbial composition and alpha diversity were thus strongly affected by introduction of family foods with high protein and fiber contents. Specifically, intake of meats, cheeses, and Danish rye bread, rich in protein and fiber, were associated with increased alpha diversity. Our results reveal that the transition from early infant feeding to family foods is a major determinant for gut microbiota development. IMPORTANCE The potential influence of maternal obesity on infant gut microbiota may occur either through vertically transmitted microbes or through the dietary habits of the family. Recent studies have suggested that the heritability of obesity may partly be caused by the transmission of “obesogenic” gut microbes. However, the findings presented here suggest that maternal obesity per se does not affect the overall composition of the gut microbiota and its development after introduction of complementary foods. Rather, progression in complementary feeding is found to be the major determinant for gut microbiota establishment. Expanding our understanding of the influence of complementary diet on the development and establishment of the gut microbiota will provide us with the knowledge to tailor a beneficial progression of our intestinal microbial community. PMID:27303699

The origin and evolution of vertebrate sex chromosomes and dosage compensation

PubMed Central

Livernois, A M; Graves, J A M; Waters, P D

2012-01-01

In mammals, birds, snakes and many lizards and fish, sex is determined genetically (either male XY heterogamy or female ZW heterogamy), whereas in alligators, and in many reptiles and turtles, the temperature at which eggs are incubated determines sex. Evidently, different sex-determining systems (and sex chromosome pairs) have evolved independently in different vertebrate lineages. Homology shared by Xs and Ys (and Zs and Ws) within species demonstrates that differentiated sex chromosomes were once homologous, and that the sex-specific non-recombining Y (or W) was progressively degraded. Consequently, genes are left in single copy in the heterogametic sex, which results in an imbalance of the dosage of genes on the sex chromosomes between the sexes, and also relative to the autosomes. Dosage compensation has evolved in diverse species to compensate for these dose differences, with the stringency of compensation apparently differing greatly between lineages, perhaps reflecting the concentration of genes on the original autosome pair that required dosage compensation. We discuss the organization and evolution of amniote sex chromosomes, and hypothesize that dosage insensitivity might predispose an autosome to evolving function as a sex chromosome. PMID:22086077

Capillary electrophoresis, a method for the determination of nucleic acid ligands covalently attached to quantum dots representing a donor of Förster resonance energy transfer.

PubMed

Datinská, Vladimíra; Klepárník, Karel; Belšánová, Barbora; Minárik, Marek; Foret, František

2018-05-09

The synthesis and determination of the structure of a Förster resonance energy transfer probe intended for the detection of specific nucleic acid sequences are described here. The probe is based on the hybridization of oligonucleotide modified quantum dots with a fluorescently labeled nucleic acid sample resulting in changes of the fluorescence emission due to the energy transfer effect. The stoichiometry distribution of oligonucleotides conjugated to quantum dots was determined by capillary electrophoresis separation. The results indicate that one to four molecules of oligonucleotide are conjugated to the surface of a single nanoparticle. This conclusion is confirmed by the course of the dependence of Förster resonance energy transfer efficiency on the concentration of fluorescently labeled complementary single-stranded nucleic acid, showing saturation. While the energy transfer efficiency of the probe hybridized with complementary nucleic acid strands was 30%, negligible efficiency was observed with a non-complementary strands. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Gray matter-changes and correlates of disease severity in schizophrenia: a statistical parametric mapping study.

PubMed

Wilke, M; Kaufmann, C; Grabner, A; Pütz, B; Wetter, T C; Auer, D P

2001-05-01

Voxel-based morphometry has recently been used successfully to detect gray matter volume reductions in schizophrenic patients. The aim of the present study was to confirm the findings on gray-matter changes and to complement these by applying the methodology to CSF-differences. Also, we wanted to determine whether a correlation exists between a clinically defined parameter of disease severity and brain morphology in schizophrenic patients. We investigated 48 schizophrenic patients and compared them with 48 strictly age- and sex-matched controls. High-resolution whole-brain MR-images were segmented and analyzed using SPM99. In a further analysis, the covariate effect of the global assessment of functioning-score (GAF) was calculated. Main findings were (i) left-dominant frontal, temporal, and insular GM-reductions and (ii) GM-increases in schizophrenic patients in the right basal ganglia and bilaterally in the superior cerebellum; (iii) CSF-space increases in patients complementary to some GM-reductions; (iv) a correlation between the GAF-score and local GM-volume in the left inferior frontal and inferior parietal lobe of schizophrenic patients. This study confirms and extends some earlier findings on GM-reduction and detected distinct GM-increases in schizophrenic patients. These changes were corroborated by complementary CSF-increases. Most importantly, a correlation could be established between two particular gray matter-regions and the overall disease severity, with more severely ill patients displaying a local GM-deficit. These findings may be of potentially large importance for both the future interpretation and design of neuroimaging studies in schizophrenia and the further elucidation of possible pathophysiological processes occurring in this disease. Copyright 2001 Academic Press.

Lymphangioleiomyomatosis Biomarkers Linked to Lung Metastatic Potential and Cell Stemness

PubMed Central

Ruiz de Garibay, Gorka; Herranz, Carmen; Llorente, Alicia; Boni, Jacopo; Serra-Musach, Jordi; Mateo, Francesca; Aguilar, Helena; Gómez-Baldó, Laia; Petit, Anna; Vidal, August; Climent, Fina; Hernández-Losa, Javier; Cordero, Álex; González-Suárez, Eva; Sánchez-Mut, José Vicente; Esteller, Manel; Llatjós, Roger; Varela, Mar; López, José Ignacio; García, Nadia; Extremera, Ana I.; Gumà, Anna; Ortega, Raúl; Plà, María Jesús; Fernández, Adela; Pernas, Sònia; Falo, Catalina; Morilla, Idoia; Campos, Miriam; Gil, Miguel; Román, Antonio; Molina-Molina, María; Ussetti, Piedad; Laporta, Rosalía; Valenzuela, Claudia; Ancochea, Julio; Xaubet, Antoni; Casanova, Álvaro; Pujana, Miguel Angel

2015-01-01

Lymphangioleiomyomatosis (LAM) is a rare lung-metastasizing neoplasm caused by the proliferation of smooth muscle-like cells that commonly carry loss-of-function mutations in either the tuberous sclerosis complex 1 or 2 (TSC1 or TSC2) genes. While allosteric inhibition of the mechanistic target of rapamycin (mTOR) has shown substantial clinical benefit, complementary therapies are required to improve response and/or to treat specific patients. However, there is a lack of LAM biomarkers that could potentially be used to monitor the disease and to develop other targeted therapies. We hypothesized that the mediators of cancer metastasis to lung, particularly in breast cancer, also play a relevant role in LAM. Analyses across independent breast cancer datasets revealed associations between low TSC1/2 expression, altered mTOR complex 1 (mTORC1) pathway signaling, and metastasis to lung. Subsequently, immunohistochemical analyses of 23 LAM lesions revealed positivity in all cases for the lung metastasis mediators fascin 1 (FSCN1) and inhibitor of DNA binding 1 (ID1). Moreover, assessment of breast cancer stem or luminal progenitor cell biomarkers showed positivity in most LAM tissue for the aldehyde dehydrogenase 1 (ALDH1), integrin-ß3 (ITGB3/CD61), and/or the sex-determining region Y-box 9 (SOX9) proteins. The immunohistochemical analyses also provided evidence of heterogeneity between and within LAM cases. The analysis of Tsc2-deficient cells revealed relative over-expression of FSCN1 and ID1; however, Tsc2-deficient cells did not show higher sensitivity to ID1-based cancer inhibitors. Collectively, the results of this study reveal novel LAM biomarkers linked to breast cancer metastasis to lung and to cell stemness, which in turn might guide the assessment of additional or complementary therapeutic opportunities for LAM. PMID:26167915

Molecular Identification of XY Sex-Reversed Female and YY Male Channel Catfish

USDA-ARS?s Scientific Manuscript database

Production of channel catfish leads U.S. aquaculture, and monosex culture may provide higher production efficiencies. Determination of phenotypic sex is labor intensive and not practical for large scale culture. Catfish have an X-Y sex determination system with monomorphic sex chromosomes. Hormonal...

A Century of Sex Determination in Flowering Plants.

PubMed

Harkess, Alex; Leebens-Mack, Jim

2017-01-01

Plants have evolved a diverse array of strategies for sexual reproduction, particularly through the modification of male and female organs at distinct points in development. The immense variation in sexual systems across the land plants provides a unique opportunity to study the genetic, epigenetic, phylogenetic, and ecological underpinnings of sex determination. Here, we reflect on more than a century of research into flowering plant sex determination, placing a particular focus on the foundational genetic and cytogenetic observations, experiments, and hypotheses. Building on the seminal work on the genetics of plant sex, modern comparative genomic analyses now allow us to address longstanding questions about sex determination and the origins of sex chromosomes. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Delimitation of the embryonic thermosensitive period for sex determination using an embryo growth model reveals a potential bias for sex ratio prediction in turtles.

PubMed

Girondot, Marc; Monsinjon, Jonathan; Guillon, Jean-Michel

2018-04-01

The sexual phenotype of the gonad is dependent on incubation temperature in many turtles, all crocodilians, and some lepidosaurians. At hatching, identification of sexual phenotype is impossible without sacrificing the neonates. For this reason, a general method to infer sexual phenotype from incubation temperatures is needed. Temperature influences sex determination during a specific period of the embryonic development, starting when the gonad begins to form. At constant incubation temperatures, this thermosensitive period for sex determination (TSP) is located at the middle third of incubation duration (MTID). When temperature fluctuates, the position of the thermosensitive period for sex determination can be shifted from the MTID because embryo growth is affected by temperature. A method is proposed to locate the thermosensitive period for sex determination based on modelling the embryo growth, allowing its precise identification from a natural regime of temperatures. Results from natural nests and simulations show that the approximation of the thermosensitive period for sex determination to the middle third of incubation duration may create a quasi-systematic bias to lower temperatures when computing the average incubation temperature during this period and thus a male-bias for sex ratio estimate. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Sex Chromosomes of Frogs: Variability and Tolerance Offer Clues to Genome Evolution and Function

PubMed Central

Malcom, Jacob W.; Kudra, Randal S.; Malone, John H.

2014-01-01

Frog sex chromosomes offer an ideal system for advancing our understanding of genome evolution and function because of the variety of sex determination systems in the group, the diversity of sex chromosome maturation states, the ease of experimental manipulation during early development. After briefly reviewing sex chromosome biology generally, we focus on what is known about frog sex determination, sex chromosome evolution, and recent, genomics-facilitated advances in the field. In closing we highlight gaps in our current knowledge of frog sex chromosomes, and suggest priorities for future research that can advance broad knowledge of gene dose and sex chromosome evolution. PMID:25031658

Determination of sex from the patella in a contemporary Spanish population.

PubMed

Peckmann, Tanya R; Meek, Susan; Dilkie, Natasha; Rozendaal, Andrew

2016-11-01

The skull and pelvis have been used for the determination of sex for unknown human remains. However, in forensic cases where skeletal remains often exhibit postmortem damage and taphonomic changes the patella may be used for the determination of sex as it is a preservationally favoured bone. The goal of the present research was to derive discriminant function equations from the patella for estimation of sex from a contemporary Spanish population. Six parameters were measured on 106 individuals (55 males and 51 females), ranging in age from 22 to 85 years old, from the Granada Osteological Collection. The statistical analyses showed that all variables were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The overall accuracy of sex classification ranged from 75.2% to 84.8% for the direct method and 75.5%-83.8% for the stepwise method. When the South African White discriminant functions were applied to the Spanish sample they showed high accuracy rates for sexing female patellae (90%-95.9%) and low accuracy rates for sexing male patellae (52.7%-58.2%). When the South African Black discriminant functions were applied to the Spanish sample they showed high accuracy rates for sexing male patellae (90.9%) and low accuracy rates for sexing female patellae (70%-75.5%). The patella was shown to be useful for sex determination in the contemporary Spanish population. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Consistent sex ratio bias of individual female dragon lizards

PubMed Central

Uller, Tobias; Mott, Beth; Odierna, Gaetano; Olsson, Mats

2006-01-01

Sex ratio evolution relies on genetic variation in either the phenotypic traits that influence sex ratios or sex-determining mechanisms. However, consistent variation among females in offspring sex ratio is rarely investigated. Here, we show that female painted dragons (Ctenophorus pictus) have highly repeatable sex ratios among clutches within years. A consistent effect of female identity could represent stable phenotypic differences among females or genetic variation in sex-determining mechanisms. Sex ratios were not correlated with female size, body condition or coloration. Furthermore, sex ratios were not influenced by incubation temperature. However, the variation among females resulted in female-biased mean population sex ratios at hatching both within and among years. PMID:17148290

Genetic mapping of sex determination in a wild strawberry, Fragaria virginiana, reveals earliest form of sex chromosome.

PubMed

Spigler, R B; Lewers, K S; Main, D S; Ashman, T-L

2008-12-01

The evolution of separate sexes (dioecy) from hermaphroditism is one of the major evolutionary transitions in plants, and this transition can be accompanied by the development of sex chromosomes. Studies in species with intermediate sexual systems are providing unprecedented insight into the initial stages of sex chromosome evolution. Here, we describe the genetic mechanism of sex determination in the octoploid, subdioecious wild strawberry, Fragaria virginiana Mill., based on a whole-genome simple sequence repeat (SSR)-based genetic map and on mapping sex determination as two qualitative traits, male and female function. The resultant total map length is 2373 cM and includes 212 markers on 42 linkage groups (mean marker spacing: 14 cM). We estimated that approximately 70 and 90% of the total F. virginiana genetic map resides within 10 and 20 cM of a marker on this map, respectively. Both sex expression traits mapped to the same linkage group, separated by approximately 6 cM, along with two SSR markers. Together, our phenotypic and genetic mapping results support a model of gender determination in subdioecious F. virginiana with at least two linked loci (or gene regions) with major effects. Reconstruction of parental genotypes at these loci reveals that both female and hermaphrodite heterogamety exist in this species. Evidence of recombination between the sex-determining loci, an important hallmark of incipient sex chromosomes, suggest that F. virginiana is an example of the youngest sex chromosome in plants and thus a novel model system for the study of sex chromosome evolution.

Sex selection and restricting abortion and sex determination.

PubMed

Zilberberg, Julie

2007-11-01

Sex selection in India and China is fostered by a limiting social structure that disallows women from performing the roles that men perform, and relegates women to a lower status level. Individual parents and individual families benefit concretely from having a son born into the family, while society, and girls and women as a group, are harmed by the widespread practice of sex selection. Sex selection reinforces oppression of women and girls. Sex selection is best addressed by ameliorating the situations of women and girls, increasing their autonomy, and elevating their status in society. One might argue that restricting or prohibiting abortion, prohibiting sex selection, and prohibiting sex determination would eliminate sex selective abortion. But this decreases women's autonomy rather than increases it. Such practices will turn underground. Sex selective infanticide, and slower death by long term neglect, could increase. If abortion is restricted, the burden is placed on women seeking abortions to show that they have a legally acceptable or legitimate reason for a desired abortion, and this seriously limits women's autonomy. Instead of restricting abortion, banning sex selection, and sex determination, it is better to address the practice of sex selection by elevating the status of women and empowering women so that giving birth to a girl is a real and positive option, instead of a detriment to the parents and family as it is currently. But, if a ban on sex selective abortion or a ban on sex determination is indeed instituted, then wider social change promoting women's status in society should be instituted simultaneously.

ddRADseq reveals determinants for temperature-dependent sex reversal in Nile tilapia on LG23.

PubMed

Wessels, Stephan; Krause, Ina; Floren, Claudia; Schütz, Ekkehard; Beck, Jule; Knorr, Christoph

2017-07-14

In Nile tilapia sex determination is governed by a male heterogametic system XX/XY either on LG1 or LG23. The latter carries a Y-specific duplicate of the amh gene, which is a testis-determining factor. Allelic variants in the amh gene demonstrated to be major triggers for autosomal and temperature-dependent sex reversal. Further, QTL on LG23 and LG20 show a temperature-responsiveness with influence on the phenotypic sex relative to the sex chromosomes. Here we present a ddRADseq based approach to identify genomic regions that show unusual large differentiation in terms of fixation index (F ST ) between temperature-treated pseudomales and non-masculinized females using a comparative genome-scan. Genome-wide associations were identified for the temperature-dependent sex using a genetically all-female population devoid of amh-ΔY. Twenty-two thousand three hundred ninety-two SNPs were interrogated for the comparison of temperature-treated pseudomales and females, which revealed the largest differentiation on LG23. Outlier F ST -values (0.35-0.44) were determined for six SNPs in the genomic interval (9,190,077-11,065,693) harbouring the amh gene (9,602,693-9,605,808), exceeding the genome-wide low F ST of 0.013. Association analysis with a set of 9104 selected SNPs confirmed that the same genomic region on LG23 exerts a significant effect on the temperature-dependent sex. This study highlights the role of LG23 in sex determination, harbouring major determinants for temperature-dependent sex reversal in Nile tilapia. Furthermore F ST outlier detection proves a powerful tool for detection of sex-determining regions in fish genomes.

Social induction of maturation and sex determination in a coral reef fish.

PubMed Central

Hobbs, Jean-Paul A.; Munday, Philip L.; Jones, Geoffrey P.

2004-01-01

Labile maturation and sex determination should be advantageous where the probability of finding a mating partner is unpredictable. Here we tested the hypothesis that the presence of a potential mating partner induces maturation and sex determination in a coral-dwelling fish, Gobiodon erythrospilus. In natural populations at Lizard Island (Great Barrier Reef), single individuals were less likely to be mature than paired individuals and they matured at a larger size, indicating plasticity in the timing of maturation. By manipulating group structure we demonstrated that both the timing of maturation and the sex of maturing individuals are socially controlled. Single juveniles did not mature, but maturation was rapidly induced by the presence of an adult partner. In addition, sex determination was found to be labile, with juveniles maturing into the opposite sex of the partner encountered. To our knowledge, this is the first experimental demonstration of social induction of maturation in conjunction with labile sex determination at maturation in vertebrates. This flexibility enables individuals to maximize their reproductive success in an environment where the timing of mate acquisition and the sex of their future partner are unpredictable. PMID:15475329

Sex-related and non-sex-related comorbidity subtypes of tic disorders: a latent class approach.

PubMed

Rodgers, S; Müller, M; Kawohl, W; Knöpfli, D; Rössler, W; Castelao, E; Preisig, M; Ajdacic-Gross, V

2014-05-01

Recent evidence suggests that there may be more than one Gilles de la Tourette syndrome (GTS)/tic disorder phenotype. However, little is known about the common patterns of these GTS/tic disorder-related comorbidities. In addition, sex-specific phenomenological data of GTS/tic disorder-affected adults are rare. Therefore, this community-based study used latent class analyses (LCA) to investigate sex-related and non-sex-related subtypes of GTS/tic disorders and their most common comorbidities. The data were drawn from the PsyCoLaus study (n = 3691), a population-based survey conducted in Lausanne, Switzerland. LCA were performed on the data of 80 subjects manifesting motor/vocal tics during their childhood/adolescence. Comorbid attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, depressive, phobia and panic symptoms/syndromes comprised the selected indicators. The resultant classes were characterized by psychosocial correlates. In LCA, four latent classes provided the best fit to the data. We identified two male-related classes. The first class exhibited both ADHD and depression. The second class comprised males with only depression. Class three was a female-related class depicting obsessive thoughts/compulsive acts, phobias and panic attacks. This class manifested high psychosocial impairment. Class four had a balanced sex proportion and comorbid symptoms/syndromes such as phobias and panic attacks. The complementary occurrence of comorbid obsessive thoughts/compulsive acts and ADHD impulsivity was remarkable. To the best of our knowledge, this is the first study applying LCA to community data of GTS symptoms/tic disorder-affected persons. Our findings support the utility of differentiating GTS/tic disorder subphenotypes on the basis of comorbid syndromes. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

Infectious, atopic and inflammatory diseases, childhood adversities and familial aggregation are independently associated with the risk for mental disorders: Results from a large Swiss epidemiological study.

PubMed

Ajdacic-Gross, Vladeta; Aleksandrowicz, Aleksandra; Rodgers, Stephanie; Mutsch, Margot; Tesic, Anja; Müller, Mario; Kawohl, Wolfram; Rössler, Wulf; Seifritz, Erich; Castelao, Enrique; Strippoli, Marie-Pierre F; Vandeleur, Caroline; von Känel, Roland; Paolicelli, Rosa; Landolt, Markus A; Witthauer, Cornelia; Lieb, Roselind; Preisig, Martin

2016-12-22

To examine the associations between mental disorders and infectious, atopic, inflammatory diseases while adjusting for other risk factors. We used data from PsyCoLaus, a large Swiss Population Cohort Study ( n = 3720; age range 35-66). Lifetime diagnoses of mental disorders were grouped into the following categories: Neurodevelopmental, anxiety (early and late onset), mood and substance disorders. They were regressed on infectious, atopic and other inflammatory diseases adjusting for sex, educational level, familial aggregation, childhood adversities and traumatic experiences in childhood. A multivariate logistic regression was applied to each group of disorders. In a complementary analysis interactions with sex were introduced via nested effects. Associations with infectious, atopic and other chronic inflammatory diseases were observable together with consistent effects of childhood adversities and familial aggregation, and less consistent effects of trauma in each group of mental disorders. Streptococcal infections were associated with neurodevelopmental disorders (men), and measles/mumps/rubella-infections with early and late anxiety disorders (women). Gastric inflammatory diseases took effect in mood disorders (both sexes) and in early disorders (men). Similarly, irritable bowel syndrome was prominent in a sex-specific way in mood disorders in women, and, moreover, was associated with early and late anxiety disorders. Atopic diseases were associated with late anxiety disorders. Acne (associations with mood disorders in men) and psoriasis (associations with early anxiety disorders in men and mood disorders in women) contributed sex-specific results. Urinary tract infections were associated with mood disorders and, in addition, in a sex-specific way with late anxiety disorders (men), and neurodevelopmental and early anxiety disorders (women). Infectious, atopic and inflammatory diseases are important risk factors for all groups of mental disorders. The sexual dimorphism of the associations is pronounced.

Alternative Splicing Profile and Sex-Preferential Gene Expression in the Female and Male Pacific Abalone Haliotis discus hannai.

PubMed

Kim, Mi Ae; Rhee, Jae-Sung; Kim, Tae Ha; Lee, Jung Sick; Choi, Ah-Young; Choi, Beom-Soon; Choi, Ik-Young; Sohn, Young Chang

2017-03-09

In order to characterize the female or male transcriptome of the Pacific abalone and further increase genomic resources, we sequenced the mRNA of full-length complementary DNA (cDNA) libraries derived from pooled tissues of female and male Haliotis discus hannai by employing the Iso-Seq protocol of the PacBio RSII platform. We successfully assembled whole full-length cDNA sequences and constructed a transcriptome database that included isoform information. After clustering, a total of 15,110 and 12,145 genes that coded for proteins were identified in female and male abalones, respectively. A total of 13,057 putative orthologs were retained from each transcriptome in abalones. Overall Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analyzed in each database showed a similar composition between sexes. In addition, a total of 519 and 391 isoforms were genome-widely identified with at least two isoforms from female and male transcriptome databases. We found that the number of isoforms and their alternatively spliced patterns are variable and sex-dependent. This information represents the first significant contribution to sex-preferential genomic resources of the Pacific abalone. The availability of whole female and male transcriptome database and their isoform information will be useful to improve our understanding of molecular responses and also for the analysis of population dynamics in the Pacific abalone.

Alternative Splicing Profile and Sex-Preferential Gene Expression in the Female and Male Pacific Abalone Haliotis discus hannai

PubMed Central

Kim, Mi Ae; Rhee, Jae-Sung; Kim, Tae Ha; Lee, Jung Sick; Choi, Ah-Young; Choi, Beom-Soon; Choi, Ik-Young; Sohn, Young Chang

2017-01-01

In order to characterize the female or male transcriptome of the Pacific abalone and further increase genomic resources, we sequenced the mRNA of full-length complementary DNA (cDNA) libraries derived from pooled tissues of female and male Haliotis discus hannai by employing the Iso-Seq protocol of the PacBio RSII platform. We successfully assembled whole full-length cDNA sequences and constructed a transcriptome database that included isoform information. After clustering, a total of 15,110 and 12,145 genes that coded for proteins were identified in female and male abalones, respectively. A total of 13,057 putative orthologs were retained from each transcriptome in abalones. Overall Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analyzed in each database showed a similar composition between sexes. In addition, a total of 519 and 391 isoforms were genome-widely identified with at least two isoforms from female and male transcriptome databases. We found that the number of isoforms and their alternatively spliced patterns are variable and sex-dependent. This information represents the first significant contribution to sex-preferential genomic resources of the Pacific abalone. The availability of whole female and male transcriptome database and their isoform information will be useful to improve our understanding of molecular responses and also for the analysis of population dynamics in the Pacific abalone. PMID:28282934

Are Story Preferences Sex-Linked for 2 and 3 Year Olds and for 4 and 5 Year Olds?

ERIC Educational Resources Information Center

Ross, Martha

This study attempted to determine: (1) whether 2-, 3-, 4-, and 5-year-old children have sex typed story preferences; and (2) whether an attempt on the part of parents to prevent sex stereotyping would affect sex typed preferences. A review of previous research discusses measures used to determine sex linked responses and the implications of…

Consistency and Generalizability of Dietary Patterns in a Multiethnic Working Population.

PubMed

Eng, Jui-Yee; Moy, Foong-Ming; Bulgiba, Awang; Rampal, Sanjay

2018-03-31

Dietary pattern analysis is a complementary method to nutrient analysis in evaluating overall diet-disease hypotheses. Although studies have been conducted to derive dietary patterns among Malaysians, their consistency across subgroups has not been examined. The study aimed to derive dietary patterns empirically and to examine the consistency and generalizability of patterns across sex, ethnicity, and urban status in a working population. This was a cross-sectional study using data from the Clustering of Lifestyle Risk Factors and Understanding its Association with Stress on Health and Well-Being among School Teachers in Malaysia study collected between August 2014 and November 2015. Dietary intake was assessed using a food frequency questionnaire, and dietary patterns were derived using factor analysis. Participants were teachers from selected public schools from three states in Peninsular Malaysia (n=4,618). Dietary patterns derived using factor analysis. Separate factor analysis was conducted by sex, ethnicity, and urban status to identify dietary patterns. Eigenvalue >2, scree plot, Velicer's minimum average partial analysis, and Horn's parallel analysis were used to determine the number of factors to retain. The interpretability of each dietary pattern was evaluated. The consistency and generalizability of dietary patterns across subgroups were assessed using the Tucker congruence coefficient. There was no subgroup-specific dietary pattern found. Thus, dietary patterns were derived using the pooled sample in the final model. Two dietary patterns (Western and Prudent) were derived. The Western dietary pattern explained 15.4% of total variance, characterized by high intakes of refined grains, animal-based foods, added fat, and sugar-sweetened beverages as well as fast food. The Prudent dietary pattern explained 11.1% of total variance and was loaded with pulses, legumes, vegetables, and fruits. The derived Western and Prudent dietary patterns were consistent and generalizable across subgroups of sex, ethnicity, and urban status. Further research is needed to explore associations between these dietary patterns and chronic diseases. Copyright © 2018 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Declining sex ratio: role of society, technology and government regulation in Faridabad district, Haryana.

PubMed

Bardia, A; Paul, E; Kapoor, S K; Anand, K

2004-01-01

A declining sex ratio at birth has been documented during censuses in India. The decline is especially more in the northern states of Haryana and Punjab. We attempted to assess the role of society (preference for a male child, awareness and acceptability of the practice of sex determination), technology (availability and affordability) and government regulation in the adverse ratio for girls in the Ballabgarh block of Haryana in northern India. The population (about 80 000) in the Ballabgarh block has been under constant demographic surveillance for the past 30 years and the data are stored electronically. This was used to determine the sex ratio at birth in the area since 1990. The data on availability of ultrasound machines was collected from the district authorities, as registration of these machines was made mandatory under the Prenatal Diagnostic Techniques Act, 1994. We interviewed 160 mothers and grandmothers to determine the awareness and acceptability of sex determination methods and practices. The demographic data for the past 10 years showed a declining sex ratio-from 881 in 1990-91 to 833 in 2000-01. The data support the view that in the initial part of this period, ultrasound was used for sex determination of all-order births but subsequently was used more in higher-order births. Our interviews with the mothers and grandmothers of the area showed that the practice of sex determination is prevalent and the attitude of the society is ambivalent. The increased availability of ultrasound machines in the area in the past 10 years corresponded to the decline in sex ratio. When the government made the practice illegal, the sex ratio improved only to fall again as the law was not implemented. Later years saw a more stringent implementation of the law and the sex ratio improved again. There is a 'demand' for sex determination technology and, therefore, this would continue to be 'supplied'. At most the 'supply' can be regulated. Social engineering efforts need to be targeted at reducing the demand if the sex ratio is to be improved.

The behavioural consequences of sex reversal in dragons

PubMed Central

Li, Hong; Holleley, Clare E.; Elphick, Melanie; Georges, Arthur

2016-01-01

Sex differences in morphology, physiology, and behaviour are caused by sex-linked genes, as well as by circulating sex-steroid levels. Thus, a shift from genotypic to environmental sex determination may create an organism that exhibits a mixture of male-like and female-like traits. We studied a lizard species (Central Bearded Dragon, Pogona vitticeps), in which the high-temperature incubation of eggs transforms genetically male individuals into functional females. Although they are reproductively female, sex-reversed dragons (individuals with ZZ genotype reversed to female phenotype) resemble genetic males rather than females in morphology (relative tail length), general behaviour (boldness and activity level), and thermoregulatory tactics. Indeed, sex-reversed ‘females’ are more male-like in some behavioural traits than are genetic males. This novel phenotype may impose strong selection on the frequency of sex reversal within natural populations, facilitating rapid shifts in sex-determining systems. A single period of high incubation temperatures (generating thermally induced sex reversal) can produce functionally female individuals with male-like (or novel) traits that enhance individual fitness, allowing the new temperature-dependent sex-determining system to rapidly replace the previous genetically based one.

A novel method for sex determination by detecting the number of X chromosomes.

PubMed

Nakanishi, Hiroaki; Shojo, Hideki; Ohmori, Takeshi; Hara, Masaaki; Takada, Aya; Adachi, Noboru; Saito, Kazuyuki

2015-01-01

A novel method for sex determination, based on the detection of the number of X chromosomes, was established. Current methods, based on the detection of the Y chromosome, can directly identify an unknown sample as male, but female gender is determined indirectly, by not detecting the Y chromosome. Thus, a direct determination of female gender is important because the quality (e.g., fragmentation and amelogenin-Y null allele) of the Y chromosome DNA may lead to a false result. Thus, we developed a novel sex determination method by analyzing the number of X chromosomes using a copy number variation (CNV) detection technique (the comparative Ct method). In this study, we designed a primer set using the amelogenin-X gene without the CNV region as the target to determine the X chromosome copy number, to exclude the influence of the CNV region from the comparative Ct value. The number of X chromosomes was determined statistically using the CopyCaller software with real-time PCR. All DNA samples from participants (20 males, 20 females) were evaluated correctly using this method with 1-ng template DNA. A minimum of 0.2-ng template DNA was found to be necessary for accurate sex determination with this method. When using ultraviolet-irradiated template DNA, as mock forensic samples, the sex of the samples could not be determined by short tandem repeat (STR) analysis but was correctly determined using our method. Thus, we successfully developed a method of sex determination based on the number of X chromosomes. Our novel method will be useful in forensic practice for sex determination.

Dmrt1 induces the male pathway in a turtle species with temperature-dependent sex determination.

PubMed

Ge, Chutian; Ye, Jian; Zhang, Haiyan; Zhang, Yi; Sun, Wei; Sang, Yapeng; Capel, Blanche; Qian, Guoying

2017-06-15

The molecular mechanism underlying temperature-dependent sex determination (TSD) has been a long-standing mystery; in particular, the thermosensitive genetic triggers for gonadal sex differentiation are largely unknown. Here, we have characterized a conserved DM domain gene, Dmrt1 , in the red-eared slider turtle Trachemys scripta ( T. scripta ), which exhibits TSD. We found that Dmrt1 has a temperature-dependent, sexually dimorphic expression pattern, preceding gonadal sex differentiation, and is capable of responding rapidly to temperature shifts and aromatase inhibitor treatment. Most importantly, loss- and gain-of-function analyses provide solid evidence that Dmrt1 is both necessary and sufficient to initiate male development in T. scripta Furthermore, the DNA methylation dynamics of the Dmrt1 promoter are tightly correlated with temperature and could mediate the impact of temperature on sex determination. Collectively, our findings demonstrate that Dmrt1 is a candidate master male sex-determining gene in this TSD species, consistent with the idea that DM domain genes are conserved during the evolution of sex determination mechanisms. © 2017. Published by The Company of Biologists Ltd.

The IMD innate immunity pathway of Drosophila influences somatic sex determination via regulation of the Doa locus.

PubMed

Zhao, Yunpo; Cocco, Claudia; Domenichini, Severine; Samson, Marie-Laure; Rabinow, Leonard

2015-11-15

The IMD pathway induces the innate immune response to infection by gram-negative bacteria. We demonstrate strong female-to-male sex transformations in double mutants of the IMD pathway in combination with Doa alleles. Doa encodes a protein kinase playing a central role in somatic sex determination through its regulation of alternative splicing of dsx transcripts. Transcripts encoding two specific Doa isoforms are reduced in Rel null mutant females, supporting our genetic observations. A role for the IMD pathway in somatic sex determination is further supported by the induction of female-to-male sex transformations by Dredd mutations in sensitized genetic backgrounds. In contrast, mutations in either dorsal or Dif, the two other NF-κB paralogues of Drosophila, display no effects on sex determination, demonstrating the specificity of IMD signaling. Our results reveal a novel role for the innate immune IMD signaling pathway in the regulation of somatic sex determination in addition to its role in response to microbial infection, demonstrating its effects on alternative splicing through induction of a crucial protein kinase. Copyright © 2015 Elsevier Inc. All rights reserved.

Ambiguous genitalia

MedlinePlus

... chromosome. These X and Y chromosomes determine the child's genetic sex. Normally, an infant inherits 1 pair of sex ... from the father. The father "determines" the genetic sex of the child. A baby who inherits the X chromosome from ...

Did sex chromosome turnover promote divergence of the major mammal groups?

PubMed Central

2016-01-01

Comparative mapping and sequencing show that turnover of sex determining genes and chromosomes, and sex chromosome rearrangements, accompany speciation in many vertebrates. Here I review the evidence and propose that the evolution of therian mammals was precipitated by evolution of the male‐determining SRY gene, defining a novel XY sex chromosome pair, and interposing a reproductive barrier with the ancestral population of synapsid reptiles 190 million years ago (MYA). Divergence was reinforced by multiple translocations in monotreme sex chromosomes, the first of which supplied a novel sex determining gene. A sex chromosome‐autosome fusion may have separated eutherians (placental mammals) from marsupials 160 MYA. Another burst of sex chromosome change and speciation is occurring in rodents, precipitated by the degradation of the Y. And although primates have a more stable Y chromosome, it may be just a matter of time before the same fate overtakes our own lineage. Also watch the video abstract. PMID:27334831

The relation of Complementary-Alternative Medicine use with glomerular filtration rate and depression in patients with chronic kidney disease at predialysis stage.

PubMed

Esen, Bennur; Atay, Ahmet Engin; Gokmen, Emel Saglam; Karakoc, Ayten; Sari, Hakan; Sarisakal, Samprie; Kahvecioglu, Serdar; Kayabasi, Hasan; Sit, Dede

2015-05-08

Complementary and alternative medicine is a broad field of health including all health care practices and methods; and their accompanying theories and beliefs. In the present study, we aimed to examine the frequency of complementary-alternative medicine use, and its relation with glomerular filtration rate and depression in patients with chronic kidney disease at predialysis stage. A total of 1053 predialysis patients; 518 female and 535 male, that were followed up with chronic kidney disease for at least 3 months were enrolled into the study. Demographic features, biochemical parameters and findings of physical examination were recorded. Their compliance to diet, and knowledge about disease were questioned. Beck depression inventory and questionnaire regarding to complementary-alternative medicine use were performed. The overall frequency of complementary-alternative medicine use was 40.3% . Total ratio of herbal products was 46%. Complementary-alternative medicine use was significantly more frequent in female or single patients, and patients that informed about chronic kidney disease or under strict diet (p:0.007, p:0.016, p:0.02, p:0.016; respectively). When glomerular filtration rate of participants were considered, complementary-alternative medicine use was similar in different stages of kidney disease. Depression was observed in 41.9% of patients and significantly frequent in patients with alternative method use (p:0.002). Depression score was higher as creatinine increases and glomerular filtration rate decreases (p:0.002; r: 0,093). We determined that complementary-alternative medicine use gradually increases at predialysis stage as glomerular filtration rate decreases and there is a strict relation between complementary-alternative medicine use and depression or female gender. Disorder related stressors may lead to seeking of alternative methods. This article is protected by copyright. All rights reserved.

Verification of sex from harvested sea otters using DNA testing

USGS Publications Warehouse

Scribner, Kim T.; Green, Ben A.; Gorbics, Carol; Bodkin, James L.

2005-01-01

We used molecular genetic methods to determine the sex of 138 sea otters (Enhydra lutris) harvested from 3 regions of Alaska from 1994 to 1997, to assess the accuracy of post‐harvest field‐sexing. We also tested each of a series of factors associated with errors in field‐sexing of sea otters, including male or female bias, age‐class bias, regional bias, and bias associated with hunt characteristics. Blind control results indicated that sex was determined with 100% accuracy using polymerase chain reaction (PCR) amplification using primers that co‐amplify the zinc finger‐Y‐X gene, located on both the mammalian Y‐ and X‐chromosomes, and Testes Determining Factor (TDF), located on the mammalian Y‐chromosome. DNA‐based sexing revealed that 12.3% of the harvested sea otters were incorrectly sexed in the field, with most errors (13 of 17) occurring as males incorrectly reported as females. Thus, female harvest was overestimated. Using logistic regression analysis, we detected no statistical association of incorrect determination of sex in the field with age class, hunt region, or hunt type. The error in field‐sexing appears to be random, at least with respect to the variables evaluated in this study.

Sex determination mode does not affect body or genital development of the central bearded dragon (Pogona vitticeps).

PubMed

Whiteley, Sarah L; Holleley, Clare E; Ruscoe, Wendy A; Castelli, Meghan; Whitehead, Darryl L; Lei, Juan; Georges, Arthur; Weisbecker, Vera

2017-01-01

The development of male- or female-specific phenotypes in squamates is typically controlled by either temperature-dependent sex determination (TSD) or chromosome-based genetic sex determination (GSD). However, while sex determination is a major switch in individual phenotypic development, it is unknownhow evolutionary transitions between GSD and TSD might impact on the evolution of squamate phenotypes, particularly the fast-evolving and diverse genitalia. Here, we take the unique opportunity of studying the impact of both sex determination mechanisms on the embryological development of the central bearded dragon ( Pogona vitticeps ). This is possible because of the transitional sex determination system of this species, in which genetically male individuals reverse sex at high incubation temperatures. This can trigger the evolutionary transition of GSD to TSD in a single generation, making P. vitticeps an ideal model organism for comparing the effects of both sex determination processes in the same species. We conducted four incubation experiments on 265 P. vitticeps eggs, covering two temperature regimes ("normal" at 28 °C and "sex reversing" at 36 °C) and the two maternal sexual genotypes (concordant ZW females or sex-reversed ZZ females). From this, we provide the first detailed staging system for the species, with a focus on genital and limb development. This was augmented by a new sex chromosome identification methodology for P. vitticeps that is non-destructive to the embryo. We found a strong correlation between embryo age and embryo stage. Aside from faster growth in 36 °C treatments, body and external genital development was entirely unperturbed by temperature, sex reversal or maternal sexual genotype. Unexpectedly, all females developed hemipenes (the genital phenotype of adult male P. vitticeps ), which regress close to hatching. The tight correlation between embryo age and embryo stage allows the precise targeting of specific developmental periods in the emerging field of molecular research on P. vitticeps . The stability of genital development in all treatments suggests that the two sex-determining mechanisms have little impact on genital evolution, despite their known role in triggering genital development. Hemipenis retention in developing female P. vitticeps , together with frequent occurrences of hemipenis-like structures during development in other squamate species, raises the possibility of a bias towards hemipenis formation in the ancestral developmental programme for squamate genitalia.

Male sex in houseflies is determined by Mdmd, a paralog of the generic splice factor gene CWC22.

PubMed

Sharma, Akash; Heinze, Svenia D; Wu, Yanli; Kohlbrenner, Tea; Morilla, Ian; Brunner, Claudia; Wimmer, Ernst A; van de Zande, Louis; Robinson, Mark D; Beukeboom, Leo W; Bopp, Daniel

2017-05-12

Across species, animals have diverse sex determination pathways, each consisting of a hierarchical cascade of genes and its associated regulatory mechanism. Houseflies have a distinctive polymorphic sex determination system in which a dominant male determiner, the M-factor, can reside on any of the chromosomes. We identified a gene, Musca domestica male determiner ( Mdmd ), as the M-factor. Mdmd originated from a duplication of the spliceosomal factor gene CWC22 ( nucampholin ). Targeted Mdmd disruption results in complete sex reversal to fertile females because of a shift from male to female expression of the downstream genes transformer and doublesex The presence of Mdmd on different chromosomes indicates that Mdmd translocated to different genomic sites. Thus, an instructive signal in sex determination can arise by duplication and neofunctionalization of an essential splicing regulator. Copyright © 2017, American Association for the Advancement of Science.

High-density linkage mapping aided by transcriptomics documents ZW sex determination system in the Chinese mitten crab Eriocheir sinensis

PubMed Central

Cui, Z; Hui, M; Liu, Y; Song, C; Li, X; Li, Y; Liu, L; Shi, G; Wang, S; Li, F; Zhang, X; Liu, C; Xiang, J; Chu, K H

2015-01-01

The sex determination system in crabs is believed to be XY-XX from karyotypy, but centromeres could not be identified in some chromosomes and their morphology is not completely clear. Using quantitative trait locus mapping of the gender phenotype, we revealed a ZW-ZZ sex determination system in Eriocheir sinensis and presented a high-density linkage map covering ~98.5% of the genome, with 73 linkage groups corresponding to the haploid chromosome number. All sex-linked markers in the family we used were located on a single linkage group, LG60, and sex linkage was confirmed by genome-wide association studies (GWAS). Forty-six markers detected by GWAS were heterozygous and segregated only in the female parent. The female LG60 was thus the putative W chromosome, with the homologous male LG60 as the Z chromosome. The putative Z and W sex chromosomes were identical in size and carried many homologous loci. Sex ratio (5:1) skewing towards females in induced triploids using unrelated animals also supported a ZW-ZZ system. Transcriptome data were used to search for candidate sex-determining loci, but only one LG60 gene was identified as an ankyrin-2 gene. Double sex- and mab3-related transcription factor 1 (Dmrt1), a Z-linked gene in birds, was located on a putative autosome. With complete genome sequencing and transcriptomic data, more genes on putative sex chromosomes will be characterised, thus leading towards a comprehensive understanding of the sex determination and differentiation mechanisms of E. sinensis, and decapod crustaceans in general. PMID:25873149

Accuracy of fetal sex determination on ultrasound examination in the first trimester of pregnancy.

PubMed

Manzanares, Sebastián; Benítez, Adara; Naveiro-Fuentes, Mariña; López-Criado, María Setefilla; Sánchez-Gila, Mar

2016-06-01

The aim of this study was to evaluate the feasibility and success rate of sex determination on transabdominal sonographic examination at 11-13 weeks' gestation and to identify factors influencing accuracy. In this prospective observational evaluation of 672 fetuses between 11 weeks' and 13 weeks + 6 days' gestational age (GA), we determined fetal sex according to the angle of the genital tubercle viewed on the midsagittal plane. We also analyzed maternal, fetal, and operator factors possibly influencing the accuracy of the determination. Fetal sex determination was feasible in 608 of the 672 fetuses (90.5%), and the prediction was correct in 532 of those 608 cases (87.5%). Fetal sex was more accurately predicted as the fetal crown-rump length (CRL), and GA increased and was less accurately predicted as the maternal body mass index increased. A CRL greater than 55.7 mm, a GA more than 12 weeks + 2 days, and a body mass index below 23.8 were identified as the best cutoff values for sex prediction. None of the other analyzed factors influenced the feasibility or accuracy of sex determination. The sex of a fetus can be accurately determined on sonographic examination in the first trimester of pregnancy; the accuracy of this prediction is influenced by the fetal CRL and GA and by the maternal body mass index. © 2015 Wiley Periodicals, Inc. J Clin Ultrasound 44:272-277, 2016. © 2015 Wiley Periodicals, Inc.

Origin of sex chromosomes in six groups of Rana rugosa frogs inferred from a sex-linked DNA marker.

PubMed

Oike, Akira; Watanabe, Koichiro; Min, Mi-Sook; Tojo, Koji; Kumagai, Masahide; Kimoto, Yuya; Yamashiro, Tadashi; Matsuo, Takanori; Kodama, Maho; Nakamura, Yoriko; Notsu, Masaru; Tochimoto, Takeyoshi; Fujita, Hiroyuki; Ota, Maki; Ito, Etsuro; Yasumasu, Shigeki; Nakamura, Masahisa

2017-08-01

Each vertebrate species, as a general rule, has either the XX/XY or ZZ/ZW chromosomes by which sex is determined. However, the Japanese Rana (R.) rugosa frog is an exception, possessing both sex-determining combinations within one species, varying with region of origin. We collected R. rugosa frogs from 104 sites around Japan and South Korea and determined the nucleotide sequences of the mitochondrial 12S ribosomal RNA gene. Based on the sequences, R. rugosa frogs were divided into four groups from Japan and one from South Korea. The ZZ/ZW type is reportedly derived from the XX/XY type, although recently a new ZZ/ZW type of R. rugosa was reported. However, it still remains unclear from where the sex chromosomes in the five groups of this species were derived. In this study, we successfully isolated a sex-linked DNA maker and used it to classify R. rugosa frogs into several groupings. From the DNA marker as well as from nucleotide analysis of the promoter region of the androgen receptor (AR) gene, we identified another female heterogametic group, designated, West-Central. The sex chromosomes in the West-Central originated from the West and Central groups. The results indicate that a sex-linked DNA marker is a verifiable tool to determine the origin of the sex chromosomes in R. rugosa frogs in which the sex-determining system has changed, during two independent events, from the male to female heterogamety. © 2017 Wiley Periodicals, Inc.

Differentiation of sex chromosomes and karyotypic evolution in the eye-lid geckos (Squamata: Gekkota: Eublepharidae), a group with different modes of sex determination.

PubMed

Pokorná, Martina; Rábová, Marie; Ráb, Petr; Ferguson-Smith, Malcolm A; Rens, Willem; Kratochvíl, Lukáš

2010-11-01

The eyelid geckos (family Eublepharidae) include both species with temperature-dependent sex determination and species where genotypic sex determination (GSD) was suggested based on the observation of equal sex ratios at several incubation temperatures. In this study, we present data on karyotypes and chromosomal characteristics in 12 species (Aeluroscalabotes felinus, Coleonyx brevis, Coleonyx elegans, Coleonyx variegatus, Eublepharis angramainyu, Eublepharis macularius, Goniurosaurus araneus, Goniurosaurus lichtenfelderi, Goniurosaurus luii, Goniurosaurus splendens, Hemitheconyx caudicinctus, and Holodactylus africanus) covering all genera of the family, and search for the presence of heteromorphic sex chromosomes. Phylogenetic mapping of chromosomal changes showed a long evolutionary stasis of karyotypes with all acrocentric chromosomes followed by numerous chromosomal rearrangements in the ancestors of two lineages. We have found heteromorphic sex chromosomes in only one species, which suggests that sex chromosomes in most GSD species of the eyelid geckos are not morphologically differentiated. The sexual difference in karyotype was detected only in C. elegans which has a multiple sex chromosome system (X(1)X(2)Y). The metacentric Y chromosome evolved most likely via centric fusion of two acrocentric chromosomes involving loss of interstitial telomeric sequences. We conclude that the eyelid geckos exhibit diversity in sex determination ranging from the absence of any sexual differences to heteromorphic sex chromosomes, which makes them an interesting system for exploring the evolutionary origin of sexually dimorphic genomes.

Identification of sex-linked SNP markers using RAD sequencing suggests ZW/ZZ sex determination in Pistacia vera L.

PubMed

Kafkas, Salih; Khodaeiaminjan, Mortaza; Güney, Murat; Kafkas, Ebru

2015-02-18

Pistachio (Pistacia vera L.) is a dioecious species that has a long juvenility period. Therefore, development of marker-assisted selection (MAS) techniques would greatly facilitate pistachio cultivar-breeding programs. The sex determination mechanism is presently unknown in pistachio. The generation of sex-linked markers is likely to reduce time, labor, and costs associated with breeding programs, and will help to clarify the sex determination system in pistachio. Restriction site-associated DNA (RAD) markers were used to identify sex-linked markers and to elucidate the sex determination system in pistachio. Eight male and eight female F1 progenies from a Pistacia vera L. Siirt × Bağyolu cross, along with the parents, were subjected to RAD sequencing in two lanes of a Hi-Seq 2000 sequencing platform. This generated 449 million reads, comprising approximately 37.7 Gb of sequences. There were 33,757 polymorphic single nucleotide polymorphism (SNP) loci between the parents. Thirty-eight of these, from 28 RAD reads, were detected as putative sex-associated loci in pistachio. Validation was performed by SNaPshot analysis in 42 mature F1 progenies and in 124 cultivars and genotypes in a germplasm collection. Eight loci could distinguish sex with 100% accuracy in pistachio. To ascertain cost-effective application of markers in a breeding program, high-resolution melting (HRM) analysis was performed; four markers were found to perfectly separate sexes in pistachio. Because of the female heterogamety in all candidate SNP loci, we report for the first time that pistachio has a ZZ/ZW sex determination system. As the reported female-to-male segregation ratio is 1:1 in all known segregating populations and there is no previous report of super-female genotypes or female heteromorphic chromosomes in pistachio, it appears that the WW genotype is not viable. Sex-linked SNP markers were identified and validated in a large germplasm and proved their suitability for MAS in pistachio. HRM analysis successfully validated the sex-linked markers for MAS. For the first time in dioecious pistachio, a female heterogamety ZW/ZZ sex determination system is suggested.

Determination of sex by armbone dimensions.

PubMed

Aye, Victor Omakoji

2010-06-15

Sex determination is a vital part of the medico-legal system but can be difficult in cases where the body is damaged. The purpose of this study was to develop a technique for sex determination from three arm-bone dimensions (wrist circumference, arm length and arm span). This knowledge can be applied in cases of mass disaster, homicide and events such as sports. Data were collected for 95 Nigerian male students and 90 Nigerian female students using physical anthropometry. Discriminant function presented the wrist dimension as the dominant contributor in this study. Combination equations for both the wrist and arm-span dimensions correctly classified sex (male/female) with an accuracy rate of 84.9%. On cross-validation, sex was also established with the same 84.9% accuracy rate. Sex determination was higher in males. Sexual dimorphism was established in this study, although the wrist circumference was more distinct than arm span; a combination of both generated sex with an accuracy prediction rate of 84.9%. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Female heterogamety in Madagascar chameleons (Squamata: Chamaeleonidae: Furcifer): differentiation of sex and neo-sex chromosomes

PubMed Central

Rovatsos, Michail; Pokorná, Martina Johnson; Altmanová, Marie; Kratochvíl, Lukáš

2015-01-01

Amniotes possess variability in sex determining mechanisms, however, this diversity is still only partially known throughout the clade and sex determining systems still remain unknown even in such a popular and distinctive lineage as chameleons (Squamata: Acrodonta: Chamaeleonidae). Here, we present evidence for female heterogamety in this group. The Malagasy giant chameleon (Furcifer oustaleti) (chromosome number 2n = 22) possesses heteromorphic Z and W sex chromosomes with heterochromatic W. The panther chameleon (Furcifer pardalis) (2n = 22 in males, 21 in females), the second most popular chameleon species in the world pet trade, exhibits a rather rare Z1Z1Z2Z2/Z1Z2W system of multiple sex chromosomes, which most likely evolved from W-autosome fusion. Notably, its neo-W chromosome is partially heterochromatic and its female-specific genetic content has expanded into the previously autosomal region. Showing clear evidence for genotypic sex determination in the panther chameleon, we resolve the long-standing question of whether or not environmental sex determination exists in this species. Together with recent findings in other reptile lineages, our work demonstrates that female heterogamety is widespread among amniotes, adding another important piece to the mosaic of knowledge on sex determination in amniotes needed to understand the evolution of this important trait. PMID:26286647

Dietary Patterns Derived Using Exploratory and Confirmatory Factor Analysis are Stable and Generalizable Across Race, Region, and Gender Subgroups in the REGARDS Study.

PubMed

Judd, Suzanne E; Letter, Abraham J; Shikany, James M; Roth, David L; Newby, P K

2014-01-01

Examining diet as a whole using dietary patterns as exposures is a complementary method to using single food or nutrients in studies of diet and disease, but the generalizability of intake patterns across race, region, and gender in the United States has not been established. To employ rigorous statistical analysis to empirically derive dietary patterns in a large bi-racial, geographically diverse population and examine whether results are stable across population subgroups. The present analysis utilized data from 21,636 participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study who completed the Block 98 food frequency questionnaire. We employed exploratory factor analysis and confirmatory factor analyses on 56 different food groups iteratively and examined differences by race, region, and sex to determine the optimal factor solution in our sample. Five dietary patterns emerged: the "Convenience" pattern was characterized by mixed dishes; the "Plant-based" pattern by fruits, vegetables, and fish; the "Sweets/Fats" pattern by sweet snacks, desserts, and fats and oils; the "Southern" pattern by fried foods, organ meat, and sweetened beverages; and the "Alcohol/Salads" pattern by beer, wine, liquor, and salads. Differences were most pronounced in the Southern pattern with black participants, those residing in the Southeast, and participants not completing high school having the highest scores. Five meaningful dietary patterns emerged in the REGARDS study and showed strong congruence across race, sex, and region. Future research will examine associations between these patterns and health outcomes to better understand racial disparities in disease and inform prevention efforts.

Genetic differentiation of eastern wolves in Algonquin Park despite bridging gene flow between coyotes and grey wolves.

PubMed

Rutledge, L Y; Garroway, C J; Loveless, K M; Patterson, B R

2010-12-01

Distinguishing genetically differentiated populations within hybrid zones and determining the mechanisms by which introgression occurs are crucial for setting effective conservation policy. Extensive hybridization among grey wolves (Canis lupus), eastern wolves (C. lycaon) and coyotes (C. latrans) in eastern North America has blurred species distinctions, creating a Canis hybrid swarm. Using complementary genetic markers, we tested the hypotheses that eastern wolves have acted as a conduit of sex-biased gene flow between grey wolves and coyotes, and that eastern wolves in Algonquin Provincial Park (APP) have differentiated following a history of introgression. Mitochondrial, Y chromosome and autosomal microsatellite genetic data provided genotypes for 217 canids from three geographic regions in Ontario, Canada: northeastern Ontario, APP and southern Ontario. Coyote mitochondrial DNA (mtDNA) haplotypes were common across regions but coyote-specific Y chromosome haplotypes were absent; grey wolf mtDNA was absent from southern regions, whereas grey wolf Y chromosome haplotypes were present in all three regions. Genetic structuring analyses revealed three distinct clusters within a genetic cline, suggesting some gene flow among species. In APP, however, 78.4% of all breeders and 11 of 15 known breeding pairs had assignment probability of Q0.8 to the Algonquin cluster, and the proportion of eastern wolf Y chromosome haplotypes in APP breeding males was higher than expected from random mating within the park (P<0.02). The data indicate that Algonquin wolves remain genetically distinct despite providing a sex-biased genetic bridge between coyotes and grey wolves. We speculate that ongoing hybridization within the park is limited by pre-mating reproductive barriers.

Rapid quantification and sex determination of forensic evidence materials.

PubMed

Andréasson, Hanna; Allen, Marie

2003-11-01

DNA quantification of forensic evidence is very valuable for an optimal use of the available biological material. Moreover, sex determination is of great importance as additional information in criminal investigations as well as in identification of missing persons, no suspect cases, and ancient DNA studies. While routine forensic DNA analysis based on short tandem repeat markers includes a marker for sex determination, analysis of samples containing scarce amounts of DNA is often based on mitochondrial DNA, and sex determination is not performed. In order to allow quantification and simultaneous sex determination on minute amounts of DNA, an assay based on real-time PCR analysis of a marker within the human amelogenin gene has been developed. The sex determination is based on melting curve analysis, while an externally standardized kinetic analysis allows quantification of the nuclear DNA copy number in the sample. This real-time DNA quantification assay has proven to be highly sensitive, enabling quantification of single DNA copies. Although certain limitations were apparent, the system is a rapid, cost-effective, and flexible assay for analysis of forensic casework samples.

Is Multifactorial Sex Determination in the House Fly, Musca domestica (L.), Stable Over Time?

PubMed

Meisel, Richard P; Davey, Taira; Son, Jae Hak; Gerry, Alec C; Shono, Toshio; Scott, Jeffrey G

2016-01-01

Sex determination pathways evolve rapidly, usually because of turnover of master regulatory genes at the top of the developmental pathway. Polygenic sex determination is expected to be a transient state between ancestral and derived conditions. However, polygenic sex determination has been observed in numerous animal species, including the house fly, Musca domestica House fly males carry a male-determining factor (M) that can be located on any chromosome, and an individual male may have multiple M factors. Females lack M and/or have a dominant allele of the Md-tra gene (Md-tra D ) that acts as a female-determining locus even in the presence of multiple copies of M. We found the frequency and linkage of M in house flies collected in Chino, CA (USA) was relatively unchanged between 1982 and 2014. The frequency of females with Md-tra D in the 2014 collection was 33.6% (n = 140). Analysis of these results, plus previously published data, revealed a strong correlation between the frequencies of Md-tra D and multiple M males, and we find that these populations are expected to have balanced sex ratios. We also find that fitness values that allow for the invasion and maintenance of multiple sex determining loci suggest that sexually antagonistic selection could be responsible for maintaining polygenic sex determination in house fly populations. The stability over time and equilibrium frequencies within populations suggest the house fly polygenic sex determination system is not in transition, and provide guidance for future investigations on the factors responsible for the polymorphism. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Repetitive sequences and epigenetic modification: inseparable partners play important roles in the evolution of plant sex chromosomes.

PubMed

Li, Shu-Fen; Zhang, Guo-Jun; Yuan, Jin-Hong; Deng, Chuan-Liang; Gao, Wu-Jun

2016-05-01

The present review discusses the roles of repetitive sequences played in plant sex chromosome evolution, and highlights epigenetic modification as potential mechanism of repetitive sequences involved in sex chromosome evolution. Sex determination in plants is mostly based on sex chromosomes. Classic theory proposes that sex chromosomes evolve from a specific pair of autosomes with emergence of a sex-determining gene(s). Subsequently, the newly formed sex chromosomes stop recombination in a small region around the sex-determining locus, and over time, the non-recombining region expands to almost all parts of the sex chromosomes. Accumulation of repetitive sequences, mostly transposable elements and tandem repeats, is a conspicuous feature of the non-recombining region of the Y chromosome, even in primitive one. Repetitive sequences may play multiple roles in sex chromosome evolution, such as triggering heterochromatization and causing recombination suppression, leading to structural and morphological differentiation of sex chromosomes, and promoting Y chromosome degeneration and X chromosome dosage compensation. In this article, we review the current status of this field, and based on preliminary evidence, we posit that repetitive sequences are involved in sex chromosome evolution probably via epigenetic modification, such as DNA and histone methylation, with small interfering RNAs as the mediator.

A novel method for determining sex in late term gestational mice based on the external genitalia

PubMed Central

Murdaugh, Laura B.; Mendoza-Romero, Haley N.; Fish, Eric W.

2018-01-01

In many experiments using fetal mice, it is necessary to determine the sex of the individual fetus. However, other than genotyping for sex-specific genes, there is no convenient, reliable method of sexing mice between gestational day (GD) 16.5 and GD 18.0. We designed a rapid, relatively simple visual method to determine the sex of mouse fetuses in the GD 16.5—GD 18.0 range that can be performed as part of a routine morphological assessment. By examining the genitalia for the presence or absence of key features, raters with minimal experience with the method were able to correctly identify the sex of embryos with 99% accuracy, while raters with no experience were 95% accurate. The critical genital features include: the presence or absence of urethral seam or proximal urethral meatus; the shape of the genitalia, and the presence or absence of an area related to the urethral plate. By comparing these morphological features of the external genitalia, we show a simple, accurate, and fast way to determine the sex of late stage mouse fetuses. Integrating this method into regular morphological assessments will facilitate the determination of sex differences in fetuses between GD 16.5 and GD 18.0. PMID:29617407

Revisiting the X:A signal that specifies Caenorhabditis elegans sexual fate.

PubMed

Gladden, John M; Farboud, Behnom; Meyer, Barbara J

2007-11-01

In Caenorhabditis elegans, sex is determined by the opposing actions of X-signal elements (XSEs) and autosomal signal elements (ASEs), which communicate the ratio of X chromosomes to sets of autosomes (X:A signal). This study delves more deeply into the mechanism by which XSEs transmit X chromosome dose. We determined the relative contributions of individual XSEs to the X:A signal and showed the order of XSE strength to be sex-1 > sex-2 > fox-1 > ceh-39 >/= region 1 XSE. sex-1 exerts a more potent influence on sex determination and dosage compensation than any other XSE by functioning in two separate capacities in the pathway: sex-1 acts upstream as an XSE to repress xol-1 and downstream as an activator of hermaphrodite development and dosage compensation. Furthermore, the process of dosage compensation affects expression of the very XSEs that control it; XSEs become fully dosage compensated once sex is determined. The X:A signal is then equivalent between XO and XX animals, causing sexual differentiation to be controlled by genes downstream of xol-1 in the sex-determination pathway. Prior to the onset of dosage compensation, the difference in XSE expression between XX and XO embryos appears to be greater than twofold, making X chromosome counting a robust process.

Sex-Biased Temporal Gene Expression in Male and Female Floral Buds of Seabuckthorn (Hippophae rhamnoides).

PubMed

Chawla, Aseem; Stobdan, Tsering; Srivastava, Ravi B; Jaiswal, Varun; Chauhan, Rajinder S; Kant, Anil

2015-01-01

Seabuckthorn is an economically important dioecious plant in which mechanism of sex determination is unknown. The study was conducted to identify seabuckthorn homologous genes involved in floral development which may have role in sex determination. Forty four putative Genes involved in sex determination (GISD) reported in model plants were shortlisted from literature survey, and twenty nine seabuckthorn homologous sequences were identified from available seabuckthorn genomic resources. Of these, 21 genes were found to differentially express in either male or female flower bud stages. HrCRY2 was significantly expressed in female flower buds only while HrCO had significant expression in male flowers only. Among the three male and female floral development stages (FDS), male stage II had significant expression of most of the GISD. Information on these sex-specific expressed genes will help in elucidating sex determination mechanism in seabuckthorn.

Sex-Biased Temporal Gene Expression in Male and Female Floral Buds of Seabuckthorn (Hippophae rhamnoides)

PubMed Central

Chawla, Aseem; Stobdan, Tsering; Srivastava, Ravi B.; Jaiswal, Varun; Chauhan, Rajinder S.; Kant, Anil

2015-01-01

Seabuckthorn is an economically important dioecious plant in which mechanism of sex determination is unknown. The study was conducted to identify seabuckthorn homologous genes involved in floral development which may have role in sex determination. Forty four putative Genes involved in sex determination (GISD) reported in model plants were shortlisted from literature survey, and twenty nine seabuckthorn homologous sequences were identified from available seabuckthorn genomic resources. Of these, 21 genes were found to differentially express in either male or female flower bud stages. HrCRY2 was significantly expressed in female flower buds only while HrCO had significant expression in male flowers only. Among the three male and female floral development stages (FDS), male stage II had significant expression of most of the GISD. Information on these sex-specific expressed genes will help in elucidating sex determination mechanism in seabuckthorn. PMID:25915052

Ocean acidification but not warming alters sex determination in the Sydney rock oyster, Saccostrea glomerata.

PubMed

Parker, Laura M; O'Connor, Wayne A; Byrne, Maria; Dove, Michael; Coleman, Ross A; Pörtner, Hans-O; Scanes, Elliot; Virtue, Patti; Gibbs, Mitchell; Ross, Pauline M

2018-02-14

Whether sex determination of marine organisms can be altered by ocean acidification and warming during this century remains a significant, unanswered question. Here, we show that exposure of the protandric hermaphrodite oyster, Saccostrea glomerata to ocean acidification, but not warming, alters sex determination resulting in changes in sex ratios. After just one reproductive cycle there were 16% more females than males. The rate of gametogenesis, gonad area, fecundity, shell length, extracellular pH and survival decreased in response to ocean acidification. Warming as a sole stressor slightly increased the rate of gametogenesis, gonad area and fecundity, but this increase was masked by the impact of ocean acidification at a level predicted for this century. Alterations to sex determination, sex ratios and reproductive capacity will have flow on effects to reduce larval supply and population size of oysters and potentially other marine organisms. © 2018 The Author(s).

Sexy transgenes: the impact of gene transfer and gene inactivation technologies on the understanding of mammalian sex determination.

PubMed

Vaiman, Daniel

2003-06-01

Amongst the various developmental pathways ending in a sound mammal, sex determination presents the peculiarity of a choice between two equally viable options: female or male. Therefore, destroying a 'male-determining gene' or a 'female-determining gene' should generally not be lethal. Genetic sex determination is divided into two consecutive steps: construction of the bipotential gonad, and then sex determination per se. The genes involved in the first step are in fact involved in the development of various body compartments, and their mutation is generally far from innocuous. From transgenic and inactivation studies carried out on the laboratory mouse, a complete picture of the two steps is beginning to emerge, where the gonad itself and the necessary ducts are shown to evolve in a very coordinate way, with well-defined sex-specificities. Compared with testis determination, the ovarian side of the picture is still relatively empty, but this situation can change rapidly as candidate ovarian genes for inactivation studies are beginning to be identified.

Gonadal expression of Sf1 and aromatase during sex determination in the red-eared slider turtle (Trachemys scripta), a reptile with temperature-dependent sex determination.

PubMed

Ramsey, Mary; Shoemaker, Christina; Crews, David

2007-12-01

Many egg-laying reptiles have temperature-dependent sex determination (TSD), where the offspring sex is determined by incubation temperature during a temperature-sensitive period (TSP) in the middle third of development. The underlying mechanism transducing a temperature cue into an ovary or testis is unknown, but it is known that steroid hormones play an important role. During the TSP, exogenous application of estrogen can override a temperature cue and produce females, while blocking the activity of aromatase (Cyp19a1), the enzyme that converts testosterone to estradiol, produces males from a female-biased temperature. The production of estrogen is a key step in ovarian differentiation for many vertebrates, including TSD reptiles, and temperature-based differences in aromatase expression during the TSP may be a critical step in ovarian determination. Steroidogenic factor-1 (Sf1) is a key gene in vertebrate sex determination and regulates many steroidogenic enzymes, including aromatase. We find that Sf1 and aromatase are differentially expressed during sex determination in the red-eared slider turtle, Trachemys scripta elegans. Sf1 is expressed at higher levels during testis development while aromatase expression increases during ovary determination. We also assayed Sf1 and aromatase response to sex-reversing treatments via temperature or the modulation of estrogen availability. Sf1 expression was redirected to low-level female-specific patterns with feminizing temperature shift or exogenous estradiol application and redirected to more intense male-specific patterns with male-producing temperature shift or inhibition of aromatase activity. Conversely, aromatase expression was redirected to more intense female-specific patterns with female-producing treatment and redirected toward diffuse low-level male-specific patterns with masculinizing sex reversal. Our data do not lend support to a role for Sf1 in the regulation of aromatase expression during slider turtle sex determination, but do support a critical role for estrogen in ovarian development.

Male-specific expression of Sox9 during gonad development of crocodile and mouse is mediated by alternative splicing of its proline-glutamine-alanine rich domain.

PubMed

Agrawal, Raman; Wessely, Oliver; Anand, Amit; Singh, Lalji; Aggarwal, Ramesh K

2009-08-01

The initial trigger for sexual differentiation is regulated by multiple ways during embryonic development. In vertebrates, chromosome-based mechanisms generally known as genetic sex determination are prevalent; however, some species, such as many reptilians, display temperature-dependent sex determination. The Sry-related transcription factor, Sox9, which is expressed by an evolutionary conserved gene, has been shown to be a key player in the process of sex determination. In the present study, we report the identification and expression of crocodile homolog of Sox9 (cpSox9) from the Indian Mugger, Crocodylus palustris. We show that cpSox9 undergoes extensive alternative splicing around the proline-glutamine-alanine rich transactivation domain that results in cpSox9 variants with presumably impaired or reduced transactivation potential. The multiple isoforms were also detected in various embryonic tissues, with some of them displaying a differential expression profile. With respect to sex differentiation, a putative unspliced full-length cpSox9 could be detected only in the genital ridge-adrenal-mesonephros complex of male, but not female embryos during the temperature-sensitive period. Importantly, we further show that this phenomenon was not restricted to the temperature-dependent sex determination species C. palustris, but was also observed in the mouse, a species exhibiting genetic sex determination. Thus, the present study describes, for the first time, a complete coding locus of Sox9 homolog from a temperature-dependent sex determination species. More importantly, we demonstrate an evolutionarily conserved role of alternative splicing resulting in transcriptional diversity and male-sex specific expression of Sox9 during testis development in vertebrates (i.e. irrespective of their underlying sex-determination mechanisms).

Sex determination in mythology and history.

PubMed

Mittwoch, Ursula

2005-02-01

The history of ideas on how the sexes became divided spans at least three thousand years. The biblical account of the origin of Eve, and the opinions of the philosophers of classical Greece, have unexpected bearings on present-day ideas. The scientific study of sex determination can be said to have begun in the 17th century with the discovery of spermatozoa, but the origin and function of the "spermatic animalcules" eluded investigators until 1841. The mammalian egg was discovered in 1827, and in the last quarter of the century fertilization was observed. The view current at that time, that sex determination was under environmental control, gave way to the idea of chromosomal determination in the first quarter of the 20th century. The study of human and other mammalian chromosomes during the third quarter of the century, and the discovery of sex-chromosome abnormalities, emphasized the importance of the Y chromosome for male sex determination. The last quarter of the century witnessed a hunt for the "testis-determining" gene, thought to be responsible for the differentiation of Sertoli cells, and culminating in the isolation of SRY (Sry in the mouse). However, an increasing number of additional genes and growth factors were found to be required for the establishment of male sex. During the same period evidence emerged that male development was accompanied by enhanced growth, both of gonads and whole embryos. An unexpected finding was the demonstration of temperature-dependent sex determination in reptiles. With the advent of the 21st century, it was shown that Sry induces cell proliferation in fetal mouse gonads, and it has been suggested that male sex differentiation in mammals requires a higher metabolic rate. These insights could lead to a better understanding and improved treatment of abnormalities of sexual development.

Analyzing the Coordinated Gene Network Underlying Temperature-Dependent Sex Determination in Reptiles

PubMed Central

Shoemaker, Christina M.; Crews, David

2009-01-01

Although gonadogenesis has been extensively studied in vertebrates with genetic sex determination, investigations at the molecular level in nontraditional model organisms with temperature-dependent sex determination are a relatively new area of research. Results show that while the key players of the molecular network underlying gonad development appear to be retained, their functions range from conserved to novel roles. In this review, we summarize experiments investigating candidate molecular players underlying temperature-dependent sex determination. We discuss some of the problems encountered unraveling this network, pose potential solutions, and suggest rewarding future directions of research. PMID:19022389

Application of a modified complementary filtering technique for increased aircraft control system frequency bandwidth in high vibration environment

NASA Technical Reports Server (NTRS)

Garren, J. F., Jr.; Niessen, F. R.; Abbott, T. S.; Yenni, K. R.

1977-01-01

A modified complementary filtering technique for estimating aircraft roll rate was developed and flown in a research helicopter to determine whether higher gains could be achieved. Use of this technique did, in fact, permit a substantial increase in system frequency bandwidth because, in comparison with first-order filtering, it reduced both noise amplification and control limit-cycle tendencies.

Fundamental Movement Skills and Fundamental Games Skills Are Complementary Pairs and Should Be Taught in Complementary Ways at All Stages of Skill Development

ERIC Educational Resources Information Center

Smith, Wayne

2016-01-01

When observing skill and determining the competency of children and youth physical education teachers often focus on the coordination dynamics within the individual in the early years and then the individual's ability to play the game as they develop. But in these game contexts the focus is often still on the individuals' actions and not the…

Integrative oncology in North America.

PubMed

Sagar, Stephen M

2006-01-01

Integrative oncology is an evolving evidence-based specialty that uses complementary therapies in concert with medical treatment to enhance its efficacy, improve symptom control, alleviate patient distress and reduce suffering. In North America the evolution of research into complementary therapies was delayed by the narrow focus of the Flexner Report. A government-funded research agenda and incorporation of complementary therapies into medical school curricula have been driven by early evidence of efficacy and patient demand. Integrative oncology focuses on the role of natural health products (botanicals, vitamins, and minerals), nutrition, acupuncture, meditation and other mind-body approaches, music therapy, touch therapies, fitness therapies, and more. Some natural health products, such as herbs and their constituent phytochemicals, may be biologic response modifiers that could increase cancer control. Current research stretches from the laboratory to health services. Institutions are exploring the effectiveness gap in their clinical services and are determining efficacy of complementary therapies through randomized controlled trials. Eventually, the goal is to establish practice guidelines through determining relative effectiveness and value through cost-utility studies. The aim of integrative oncology should be one medicine, not alternative; it should be patient-focused; it should be evidence-based; and it should provide the best care for cancer cure, prevention, symptom control, and quality of life.

Estimation of land-surface evaporation at four forest sites across Japan with the new nonlinear complementary method.

PubMed

Ai, Zhipin; Wang, Qinxue; Yang, Yonghui; Manevski, Kiril; Zhao, Xin; Eer, Deni

2017-12-19

Evaporation from land surfaces is a critical component of the Earth water cycle and of water management strategies. The complementary method originally proposed by Bouchet, which describes a linear relation between actual evaporation (E), potential evaporation (E po ) and apparent potential evaporation (E pa ) based on routinely measured weather data, is one of the various methods for evaporation calculation. This study evaluated the reformulated version of the original method, as proposed by Brutsaert, for forest land cover in Japan. The new complementary method is nonlinear and based on boundary conditions with strictly physical considerations. The only unknown parameter (α e ) was for the first time determined for various forest covers located from north to south across Japan. The values of α e ranged from 0.94 to 1.10, with a mean value of 1.01. Furthermore, the calculated evaporation with the new method showed a good fit with the eddy-covariance measured values, with a determination coefficient of 0.78 and a mean bias of 4%. Evaluation results revealed that the new nonlinear complementary relation performs better than the original linear relation in describing the relationship between E/E pa and E po /E pa , and also in depicting the asymmetry variation between E pa /E po and E/E po .

Conserved Domains in the Transformer Protein Act Complementary to Regulate Sex-Specific Splicing of Its Own Pre-mRNA.

PubMed

Tanaka, Arisa; Aoki, Fugaku; Suzuki, Masataka G

2018-05-26

The transformer (tra) gene, which is a female-determining master gene in the housefly Musca domestica, acts as a memory device for sex determination via its auto-regulatory function, i.e., through the contribution of the TRA protein to female-specific splicing of its own pre-mRNA. The TRA protein contains 4 small domains that are specifically conserved among TRA proteins (domains 1-4). Domain 2, also named TRA-CAM domain, is the most conserved, but its function remains unknown. To examine whether these domains are involved in the auto-regulatory function, we performed in vitro splicing assays using a tra minigene containing a partial genomic sequence of the M. domestica tra (Mdtra) gene. Co-transfection of the Mdtra minigene and an MdTRA protein expression vector into cultured insect cells strongly induced female-specific splicing of the minigene. A series of deletion mutation analyses demonstrated that these domains act complementarily to induce female-specific splicing. Domain 1 and the TRA-CAM domain were necessary for the female-specific splicing when the MdTRA protein lacked both domains 3 and 4. In this situation, mutation of the well-conserved 3 amino acids (GEG) in the TRA-CAM domain significantly reduced the female-specific splicing activity of MdTRA. GST-pull down analyses demonstrated that the MdTRA protein specifically enriched on the male-specific exonic region (exon 2b), which contains the putative TRA/TRA-2 binding sites, and that the GEG mutation disrupts this enrichment. Since the MdTRA protein interacts with its own pre-mRNA through TRA-2, our findings suggest that the conserved amino acid residues in the TRA-CAM domain may be crucial for the interaction between MdTRA and TRA-2, enhancing MdTRA recruitment on its pre-mRNA to induce female-specific splicing of tra in the housefly. © 2018 S. Karger AG, Basel.

Maintaining continuity through a scientific revolution: a rereading of E. B. Wilson and T. H. Morgan on sex determination and Mendelism.

PubMed

Kingsland, Sharon E

2007-09-01

A rereading of the American scientific literature on sex determination from 1902 to 1926 leads to a different understanding of the construction of the Mendelian-chromosome theory after 1910. There was significant intellectual continuity, which has not been properly appreciated, underlying this scientific "revolution." After reexamining the relationship between the ideas of key scientists, in particular Edmund B. Wilson and Thomas Hunt Morgan, I argue that, contrary to the historical literature, Wilson and Morgan did not adopt opposing views on Mendelism and sex determination. Rather, each preferred a non-Mendelian explanation of the determination of sex. Around 1910, both integrated the Mendelian and non-Mendelian theories to create a synthetic theory. One problem was the need to avoid an overly deterministic view of sex while also accepting the validity of Mendelism. Morgan's discovery of mutations on the X chromosome takes on different significance when set in the context of the debate about sex determination, and Calvin Bridges's work on sex determination is better seen as a development of Morgan's ideas, rather than a departure from them. Conclusions point to the role of synthesis within fields as a way to advance scientific theories and reflect on the relationship between synthesis and explanatory "pluralism" in biology.

determination of sex in south african blacks by discriminant function analysis of mandibular linear dimensions : A preliminary investigation using the zulu local population.

PubMed

Franklin, Daniel; O'Higgins, Paul; Oxnard, Charles E; Dadour, Ian

2006-12-01

The determination of sex is a critical component in forensic anthropological investigation. The literature attests to numerous metrical standards, each utilizing diffetent skeletal elements, for sex determination in South A frican Blacks. Metrical standards are popular because they provide a high degree of expected accuracy and are less error-prone than subjective nonmetric visual techniques. We note, however, that there appears to be no established metric mandible discriminant function standards for sex determination in this population.We report here on a preliminary investigation designed to evaluate whether the mandible is a practical element for sex determination in South African Blacks. The sample analyzed comprises 40 nonpathological Zulu individuals drawn from the R.A. Dart Collection. Ten linear measurements, obtained from mathematically trans-formed three-dimensional landmark data, are analyzed using basic univariate statistics and discriminant function analyses. Seven of the 10 measurements examined are found to be sexually dimorphic; the dimensions of the ramus are most dimorphic. The sex classification accuracy of the discriminant functions ranged from 72.5 to 87.5% for the univariate method, 92.5% for the stepwise method, and 57.5 to 95% for the direct method. We conclude that the mandible is an extremely useful element for sex determination in this population.

Comparison of Feeding Practices in Infants in the WIC Supplemental Nutrition Program Who Were Enrolled in Child Care as Opposed to Those with Parent Care Only.

PubMed

Kim, Juhee; Mathai, Rose Ann

2015-09-01

The environment or setting to which an infant is exposed is crucial to establishing healthy eating habits and to preventing obesity. This study aimed to compare infant feeding practices and complementary food type between parent care (PC) and childcare (CC) settings among infants receiving the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC). This study sampled 105 dyads of mothers and infants between 2 to 8 months of age from a WIC office in Central Illinois. Mothers completed a cross-sectional survey to assess their infant feeding practices and demographic characteristics. CC was defined as infants receiving 10 hours or more per week of care from a nonparental caregiver. Almost half of the infants (44%) were enrolled in CC. Infants in CC had an average of 29 hours of care per week compared with 0.64 hours in the PC group (p<0.01). There were no differences between the two groups in age, sex, race/ethnicity, preterm birth, and birth weight. Overall, there were no significant differences in breastfeeding initiation and duration. The average age at formula introduction was earlier for PC infants (0.90 ± 1.16 months) than for CC infants (1.66 ± 1.64 months) (p = 0.03). PC infants stopped breastfeeding at 1.96 ± 1.15 months compared with 2.31 ± 1.64 months for CC infants (p = 0.080). Among complementary foods introduced to infants, the primary food type was infant cereal, followed by baby food of fruits and vegetables, 100% fruit juice, and meat-based baby food. The timing of introduction and the types of complementary foods were similar between study groups. CC use is not a significant influence on breastfeeding rates, introduction of complementary foods, and types of complementary foods; however, it does influence when formula is introduced. The findings support the need for infant nutrition education and breastfeeding promotion targeting WIC mothers, regardless of their pattern of CC.

Sex determination of human remains from peptides in tooth enamel.

PubMed

Stewart, Nicolas Andre; Gerlach, Raquel Fernanda; Gowland, Rebecca L; Gron, Kurt J; Montgomery, Janet

2017-12-26

The assignment of biological sex to archaeological human skeletons is a fundamental requirement for the reconstruction of the human past. It is conventionally and routinely performed on adults using metric analysis and morphological traits arising from postpubertal sexual dimorphism. A maximum accuracy of ∼95% is possible if both the cranium and os coxae are present and intact, but this is seldom achievable for all skeletons. Furthermore, for infants and juveniles, there are no reliable morphological methods for sex determination without resorting to DNA analysis, which requires good DNA survival and is time-consuming. Consequently, sex determination of juvenile remains is rarely undertaken, and a dependable and expedient method that can correctly assign biological sex to human remains of any age is highly desirable. Here we present a method for sex determination of human remains by means of a minimally destructive surface acid etching of tooth enamel and subsequent identification of sex chromosome-linked isoforms of amelogenin, an enamel-forming protein, by nanoflow liquid chromatography mass spectrometry. Tooth enamel is the hardest tissue in the human body and survives burial exceptionally well, even when the rest of the skeleton or DNA in the organic fraction has decayed. Our method can reliably determine the biological sex of humans of any age using a body tissue that is difficult to cross-contaminate and is most likely to survive. The application of this method will make sex determination of adults and, for the first time, juveniles a reliable and routine activity in future bioarcheological and medico-legal science contexts. Copyright © 2017 the Author(s). Published by PNAS.

Direct LAMP Assay without Prior DNA Purification for Sex Determination of Papaya.

PubMed

Tsai, Chi-Chu; Shih, Huei-Chuan; Ko, Ya-Zhu; Wang, Ren-Huang; Li, Shu-Ju; Chiang, Yu-Chung

2016-09-24

Papaya (Carica papaya L.) is an economically important tropical fruit tree with hermaphrodite, male and female sex types. Hermaphroditic plants are the major type used for papaya production because their fruits have more commercial advantages than those of female plants. Sex determination of the seedlings, or during the early growth stages, is very important for the papaya seedling industry. Thus far, the only method for determining the sex type of a papaya at the seedling stage has been DNA analysis. In this study, a molecular technique-based on DNA analysis-was developed for detecting male-hermaphrodite-specific markers to examine the papaya's sex type. This method is based on the loop-mediated isothermal amplification (LAMP) and does not require prior DNA purification. The results show that the method is an easy, efficient, and inexpensive way to determine a papaya's sex. This is the first report on the LAMP assay, using intact plant materials-without DNA purification-as samples for the analysis of sex determination of papaya. We found that using high-efficiency DNA polymerase was essential for successful DNA amplification, using trace intact plant material as a template DNA source.

Evolution of sex determination systems with heterogametic males and females in silene.

PubMed

Slancarova, Veronika; Zdanska, Jana; Janousek, Bohuslav; Talianova, Martina; Zschach, Christian; Zluvova, Jitka; Siroky, Jiri; Kovacova, Viera; Blavet, Hana; Danihelka, Jiri; Oxelman, Bengt; Widmer, Alex; Vyskot, Boris

2013-12-01

The plant genus Silene has become a model for evolutionary studies of sex chromosomes and sex-determining mechanisms. A recent study performed in Silene colpophylla showed that dioecy and the sex chromosomes in this species evolved independently from those in Silene latifolia, the most widely studied dioecious Silene species. The results of this study show that the sex-determining system in Silene otites, a species related to S. colpophylla, is based on female heterogamety, a sex determination system that is unique among the Silene species studied to date. Our phylogenetic data support the placing of S. otites and S. colpophylla in the subsection Otites and the analysis of ancestral states suggests that the most recent common ancestor of S. otites and S. colpophylla was most probably dioecious. These observations imply that a switch from XX/XY sex determination to a ZZ/ZW system (or vice versa) occurred in the subsection Otites. This is the first report of two different types of heterogamety within one plant genus of this mostly nondioecious plant family. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

A simple PCR-based marker to determine sex in aspen.

PubMed

Pakull, B; Kersten, B; Lüneburg, J; Fladung, M

2015-01-01

The genus Populus features a genetically controlled sex determination system, located on chromosome 19. However, different Populus species vary in the position of the sex-linked region on the respective chromosome and the apparent heterogametic sex, and the precise mechanism of sex determination in Populus is still unknown. Using next generation sequencing of pooled samples of male and female aspens, we identified the aspen homologue of the P. trichocarpa gene Potri.019G047300 ('TOZ19') to be male-specific. While in P. tremuloides, the complete gene is missing in the genome of female plants, a short fragment of the 3'-part of the gene is still present in P. tremula females. The male-specific presence and transcription of TOZ19 was further verified using PCR in various different aspen individuals and RT-PCR expression analysis. TOZ19 is potentially involved in early steps of flower development, and represents an interesting candidate gene for involvement in sex determination in aspen. Regardless of its role as candidate gene, TOZ19 represents an ideal marker for determination of the sex of non-flowering aspen individuals or seedlings. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

Direct LAMP Assay without Prior DNA Purification for Sex Determination of Papaya

PubMed Central

Tsai, Chi-Chu; Shih, Huei-Chuan; Ko, Ya-Zhu; Wang, Ren-Huang; Li, Shu-Ju; Chiang, Yu-Chung

2016-01-01

Papaya (Carica papaya L.) is an economically important tropical fruit tree with hermaphrodite, male and female sex types. Hermaphroditic plants are the major type used for papaya production because their fruits have more commercial advantages than those of female plants. Sex determination of the seedlings, or during the early growth stages, is very important for the papaya seedling industry. Thus far, the only method for determining the sex type of a papaya at the seedling stage has been DNA analysis. In this study, a molecular technique—based on DNA analysis—was developed for detecting male-hermaphrodite-specific markers to examine the papaya’s sex type. This method is based on the loop-mediated isothermal amplification (LAMP) and does not require prior DNA purification. The results show that the method is an easy, efficient, and inexpensive way to determine a papaya’s sex. This is the first report on the LAMP assay, using intact plant materials-without DNA purification-as samples for the analysis of sex determination of papaya. We found that using high-efficiency DNA polymerase was essential for successful DNA amplification, using trace intact plant material as a template DNA source. PMID:27669237

De Novo Assembly of the Manila Clam Ruditapes philippinarum Transcriptome Provides New Insights into Expression Bias, Mitochondrial Doubly Uniparental Inheritance and Sex Determination

PubMed Central

Ghiselli, Fabrizio; Milani, Liliana; Chang, Peter L.; Hedgecock, Dennis; Davis, Jonathan P.; Nuzhdin, Sergey V.; Passamonti, Marco

2012-01-01

Males and females share the same genome, thus, phenotypic divergence requires differential gene expression and sex-specific regulation. Accordingly, the analysis of expression patterns is pivotal to the understanding of sex determination mechanisms. Many bivalves are stable gonochoric species, but the mechanism of gonad sexualization and the genes involved are still unknown. Moreover, during the period of sexual rest, a gonad is not present and sex cannot be determined. A mechanism associated with germ line differentiation in some bivalves, including the Manila clam Ruditapes philippinarum, is the doubly uniparental inheritance (DUI) of mitochondria, a variation of strict maternal inheritance. Two mitochondrial lineages are present, one transmitted through eggs and the other through sperm, as well as a mother-dependent sex bias of the progeny. We produced a de novo annotation of 17,186 transcripts from R. philippinarum and compared the transcriptomes of males and females and identified 1,575 genes with strong sex-specific expression and 166 sex-specific single nucleotide polymorphisms, obtaining preliminary information about genes that could be involved in sex determination. Then we compared the transcriptomes between a family producing predominantly females and a family producing predominantly males to identify candidate genes involved in regulation of sex-specific aspects of DUI system, finding a relationship between sex bias and differential expression of several ubiquitination genes. In mammalian embryos, sperm mitochondria are degraded by ubiquitination. A modification of this mechanism is hypothesized to be responsible for the retention of sperm mitochondria in male embryos of DUI species. Ubiquitination can additionally regulate gene expression, playing a role in sex determination of several animals. These data enable us to develop a model that incorporates both the DUI literature and our new findings. PMID:21976711

Zebrafish monosex population reveals female dominance in sex determination and earliest events of gonad differentiation.

PubMed

Tong, Sok-Keng; Hsu, Hwei-Jan; Chung, Bon-chu

2010-08-15

The zebrafish is a popular model for genetic analysis and its sex differentiation has been the focus of attention for breeding purposes. Despite numerous efforts, very little is known about the mechanism of zebrafish sex determination. The lack of discernible sex chromosomes and the difficulty of distinguishing the sex of juvenile fish are two major obstacles that hamper the progress in such studies. To alleviate these problems, we have developed a scheme involving methyltestosterone treatment followed by natural mating to generate fish with predictable sex trait. Female F1 fish that gave rise to all-female offspring were generated. This predictable sex trait enables characterization of gonadal development in juvenile fish by histological examination and gene expression analysis. We found the first sign of zebrafish sex differentiation to be ovarian gonocyte proliferation and differentiation at 10 to 12 days post-fertilization (dpf). Somatic genes were expressed indifferently at 10 to 17 dpf, and then became sexually dimorphic at three weeks. This result indicates clear distinction of male and female gonads derived independently from primordial gonads. We classified the earliest stages of zebrafish sex determination into the initial preparation followed by female germ cell growth, oocyte differentiation, and somatic differentiation. Our genetic selection scheme matches the prediction that female-dominant genetic factors are required to determine zebrafish sex. Copyright 2010 Elsevier Inc. All rights reserved.

Transcriptome analysis by strand-specific sequencing of complementary DNA

PubMed Central

Parkhomchuk, Dmitri; Borodina, Tatiana; Amstislavskiy, Vyacheslav; Banaru, Maria; Hallen, Linda; Krobitsch, Sylvia; Lehrach, Hans; Soldatov, Alexey

2009-01-01

High-throughput complementary DNA sequencing (RNA-Seq) is a powerful tool for whole-transcriptome analysis, supplying information about a transcript's expression level and structure. However, it is difficult to determine the polarity of transcripts, and therefore identify which strand is transcribed. Here, we present a simple cDNA sequencing protocol that preserves information about a transcript's direction. Using Saccharomyces cerevisiae and mouse brain transcriptomes as models, we demonstrate that knowing the transcript's orientation allows more accurate determination of the structure and expression of genes. It also helps to identify new genes and enables studying promoter-associated and antisense transcription. The transcriptional landscapes we obtained are available online. PMID:19620212

Transcriptome analysis by strand-specific sequencing of complementary DNA.

PubMed

Parkhomchuk, Dmitri; Borodina, Tatiana; Amstislavskiy, Vyacheslav; Banaru, Maria; Hallen, Linda; Krobitsch, Sylvia; Lehrach, Hans; Soldatov, Alexey

2009-10-01

High-throughput complementary DNA sequencing (RNA-Seq) is a powerful tool for whole-transcriptome analysis, supplying information about a transcript's expression level and structure. However, it is difficult to determine the polarity of transcripts, and therefore identify which strand is transcribed. Here, we present a simple cDNA sequencing protocol that preserves information about a transcript's direction. Using Saccharomyces cerevisiae and mouse brain transcriptomes as models, we demonstrate that knowing the transcript's orientation allows more accurate determination of the structure and expression of genes. It also helps to identify new genes and enables studying promoter-associated and antisense transcription. The transcriptional landscapes we obtained are available online.

Sox5 is involved in germ-cell regulation and sex determination in medaka following co-option of nested transposable elements.

PubMed

Schartl, Manfred; Schories, Susanne; Wakamatsu, Yuko; Nagao, Yusuke; Hashimoto, Hisashi; Bertin, Chloé; Mourot, Brigitte; Schmidt, Cornelia; Wilhelm, Dagmar; Centanin, Lazaro; Guiguen, Yann; Herpin, Amaury

2018-01-29

Sex determination relies on a hierarchically structured network of genes, and is one of the most plastic processes in evolution. The evolution of sex-determining genes within a network, by neo- or sub-functionalization, also requires the regulatory landscape to be rewired to accommodate these novel gene functions. We previously showed that in medaka fish, the regulatory landscape of the master male-determining gene dmrt1bY underwent a profound rearrangement, concomitantly with acquiring a dominant position within the sex-determining network. This rewiring was brought about by the exaptation of a transposable element (TE) called Izanagi, which is co-opted to act as a silencer to turn off the dmrt1bY gene after it performed its function in sex determination. We now show that a second TE, Rex1, has been incorporated into Izanagi. The insertion of Rex1 brought in a preformed regulatory element for the transcription factor Sox5, which here functions in establishing the temporal and cell-type-specific expression pattern of dmrt1bY. Mutant analysis demonstrates the importance of Sox5 in the gonadal development of medaka, and possibly in mice, in a dmrt1bY-independent manner. Moreover, Sox5 medaka mutants have complete female-to-male sex reversal. Our work reveals an unexpected complexity in TE-mediated transcriptional rewiring, with the exaptation of a second TE into a network already rewired by a TE. We also show a dual role for Sox5 during sex determination: first, as an evolutionarily conserved regulator of germ-cell number in medaka, and second, by de novo regulation of dmrt1 transcriptional activity during primary sex determination due to exaptation of the Rex1 transposable element.

Fluorometric aptasensing of the neonicotinoid insecticide acetamiprid by using multiple complementary strands and gold nanoparticles.

PubMed

Bahreyni, Amirhossein; Yazdian-Robati, Rezvan; Ramezani, Mohammad; Abnous, Khalil; Taghdisi, Seyed Mohammad

2018-04-29

A fluorometric aptamer-based assay was developed for ultrasensitive and selective determination of the neonicotinoid insecticide acetamiprid. The method is based on the use of an aptamer against acetamiprid, multiple complementary strands (CSs), and gold nanoparticles (AuNPs). It is found that by using different CSs, the sensitivity and selectivity of the method is enhanced. On addition of acetamiprid to the aptamer, they will bind to each other and CS1-fluorescein (FAM)-labeled CS2 (as a dsDNA) will be formed. The FAM-labeled dsDNA does not bind to the AuNPs (as a strong quencher) and remains free in the environment, resulting in a strong fluorescence intensity. Without the introduction of acetamiprid, FAM-labeled CS2 binds to AuNPs directly and indirectly through hybridization with CS3 immobilized on the surface of the AuNPs. So, the fluorescence intensity of FAM-labeled CS2 is significantly quenched by AuNPs. The method can detect acetamiprid in the 5 to 50 nM concentration range with a 2.8 nM detection limit. The assay was applied to the determination of acetamiprid in spiked tap water where is gave recoveries that ranged between 95.4% and 94.4%. Graphical abstract (a) In the presence of acetamiprid, aptamer interacts with acetamiprid. The formation of aptamer/acetamiprid causes pairing of complementary strand 1 with FAM-labeled complementary strand, leading to a strong fluorescence intensity. (b) In the absence of acetamiprid, aptamer is hybridized with complementary strand 1. Thus, a very weak fluorescence signal is detected.

[Legal recognition of transsexuality in Chile through the judicial procedure for name change].

PubMed

Muñoz León, Fernando

2015-08-01

Do transsexual people in Chile have a right to have their gender identity or their sex reassignment legally recognized? The absence of any legislation on gender identity or transsexualism could lead us to believe that it is not the case. However, a quantitative review of decisions issued by Chilean courts during the last years on name-and sex-change requests filed by transsexual people reveals that most of these courts have accepted these requests. From the perspective of the well-being of transsexual people, this is a positive result. However, the fact that a few rejections exist reminds us of the need to enact an explicit legislation in this issue. Lastly, a qualitative analysis of those decisions suggests that the traditional reluctance of courts to interpret the law in a creative way has been overcome in these cases by the use of knowledge and discourses belonging to healthcare sciences. This is an example of an epistemological complementariness between medicine and law.

Triploid Colubrid Snake Provides Insight into the Mechanism of Sex Determination in Advanced Snakes.

PubMed

Rovatsos, Michail; Augstenová, Barbora; Altmanová, Marie; Sloboda, Michal; Kodym, Petr; Kratochvíl, Lukáš

2018-06-19

The advanced snakes (Caenophidia), the important amniote lineage encompassing more than 3,000 living species, possess highly conserved female heterogamety across all families. However, we still lack any knowledge on the gene(s) and the molecular mechanism controlling sex determination. Triploid individuals spontaneously appear in populations of diploid species and can provide an important insight into the evolution of sex determination. Here, we report a case of spontaneous triploidy in a male of the twin-spotted ratsnake (Elaphe bimaculata) with ZZW sex chromosomes. We speculate that as both ZZ and ZZW individuals develop male gonads, the ratio between the number of Z chromosomes and autosomes, and not the presence of the W chromosome in the genome, drives sex determination in the advanced snakes. © 2018 S. Karger AG, Basel.

Identification of RAN1 orthologue associated with sex determination through whole genome sequencing analysis in fig (Ficus carica L.).

PubMed

Mori, Kazuki; Shirasawa, Kenta; Nogata, Hitoshi; Hirata, Chiharu; Tashiro, Kosuke; Habu, Tsuyoshi; Kim, Sangwan; Himeno, Shuichi; Kuhara, Satoru; Ikegami, Hidetoshi

2017-01-25

With the aim of identifying sex determinants of fig, we generated the first draft genome sequence of fig and conducted the subsequent analyses. Linkage analysis with a high-density genetic map established by a restriction-site associated sequencing technique, and genome-wide association study followed by whole-genome resequencing analysis identified two missense mutations in RESPONSIVE-TO-ANTAGONIST1 (RAN1) orthologue encoding copper-transporting ATPase completely associated with sex phenotypes of investigated figs. This result suggests that RAN1 is a possible sex determinant candidate in the fig genome. The genomic resources and genetic findings obtained in this study can contribute to general understanding of Ficus species and provide an insight into fig's and plant's sex determination system.

Mapping platypus SOX genes; autosomal location of SOX9 excludes it from sex determining role.

PubMed

Wallis, M C; Delbridge, M L; Pask, A J; Alsop, A E; Grutzner, F; O'Brien, P C M; Rens, W; Ferguson-Smith, M A; Graves, J A M

2007-01-01

In the absence of an SRY orthologue the platypus sex determining gene is unknown, so genes in the human testis determining pathway are of particular interest as candidates. SOX9 is an attractive choice because SOX9 deletions cause male-to-female sex reversal in humans and mice, and SOX9 duplications cause female-to-male sex reversal. We have localized platypus SOX9, as well as the related SOX10, to platypus chromosomes 15 and 10, respectively, the first assignments to these platypus chromosomes, and the first comparative mapping markers from human chromosomes 17 and 22. The autosomal localization of platypus SOX9 in this study contradicts the hypothesis that SOX9 acts as the sex determining switch in platypus. Copyright 2007 S. Karger AG, Basel.

Identification of SOX3 as an XX male sex reversal gene in mice and humans.

PubMed

Sutton, Edwina; Hughes, James; White, Stefan; Sekido, Ryohei; Tan, Jacqueline; Arboleda, Valerie; Rogers, Nicholas; Knower, Kevin; Rowley, Lynn; Eyre, Helen; Rizzoti, Karine; McAninch, Dale; Goncalves, Joao; Slee, Jennie; Turbitt, Erin; Bruno, Damien; Bengtsson, Henrik; Harley, Vincent; Vilain, Eric; Sinclair, Andrew; Lovell-Badge, Robin; Thomas, Paul

2011-01-01

Sex in mammals is genetically determined and is defined at the cellular level by sex chromosome complement (XY males and XX females). The Y chromosome-linked gene sex-determining region Y (SRY) is believed to be the master initiator of male sex determination in almost all eutherian and metatherian mammals, functioning to upregulate expression of its direct target gene Sry-related HMG box-containing gene 9 (SOX9). Data suggest that SRY evolved from SOX3, although there is no direct functional evidence to support this hypothesis. Indeed, loss-of-function mutations in SOX3 do not affect sex determination in mice or humans. To further investigate Sox3 function in vivo, we generated transgenic mice overexpressing Sox3. Here, we report that in one of these transgenic lines, Sox3 was ectopically expressed in the bipotential gonad and that this led to frequent complete XX male sex reversal. Further analysis indicated that Sox3 induced testis differentiation in this particular line of mice by upregulating expression of Sox9 via a similar mechanism to Sry. Importantly, we also identified genomic rearrangements within the SOX3 regulatory region in three patients with XX male sex reversal. Together, these data suggest that SOX3 and SRY are functionally interchangeable in sex determination and support the notion that SRY evolved from SOX3 via a regulatory mutation that led to its de novo expression in the early gonad.

Identification of SOX3 as an XX male sex reversal gene in mice and humans

PubMed Central

Sutton, Edwina; Hughes, James; White, Stefan; Sekido, Ryohei; Tan, Jacqueline; Arboleda, Valerie; Rogers, Nicholas; Knower, Kevin; Rowley, Lynn; Eyre, Helen; Rizzoti, Karine; McAninch, Dale; Goncalves, Joao; Slee, Jennie; Turbitt, Erin; Bruno, Damien; Bengtsson, Henrik; Harley, Vincent; Vilain, Eric; Sinclair, Andrew; Lovell-Badge, Robin; Thomas, Paul

2010-01-01

Sex in mammals is genetically determined and is defined at the cellular level by sex chromosome complement (XY males and XX females). The Y chromosome–linked gene sex-determining region Y (SRY) is believed to be the master initiator of male sex determination in almost all eutherian and metatherian mammals, functioning to upregulate expression of its direct target gene Sry-related HMG box–containing gene 9 (SOX9). Data suggest that SRY evolved from SOX3, although there is no direct functional evidence to support this hypothesis. Indeed, loss-of-function mutations in SOX3 do not affect sex determination in mice or humans. To further investigate Sox3 function in vivo, we generated transgenic mice overexpressing Sox3. Here, we report that in one of these transgenic lines, Sox3 was ectopically expressed in the bipotential gonad and that this led to frequent complete XX male sex reversal. Further analysis indicated that Sox3 induced testis differentiation in this particular line of mice by upregulating expression of Sox9 via a similar mechanism to Sry. Importantly, we also identified genomic rearrangements within the SOX3 regulatory region in three patients with XX male sex reversal. Together, these data suggest that SOX3 and SRY are functionally interchangeable in sex determination and support the notion that SRY evolved from SOX3 via a regulatory mutation that led to its de novo expression in the early gonad. PMID:21183788

Timing of introduction of complementary food: short- and long-term health consequences.

PubMed

Przyrembel, Hildegard

2012-01-01

Complementary food is needed when breast milk (or infant formula) alone is no longer sufficient for both nutritional and developmental reasons. The timing of its introduction, therefore, is an individual decision, although 6 months of exclusive breastfeeding can be recommended for most healthy term infants. The new foods are intended to 'complement' ongoing breastfeeding with those dietary items whose intake has become marginal or insufficient. Both breastfeeding and complementary feeding can have direct or later consequences on health. The evaluation of consequences of both early and late introduction of complementary food can neither disregard the effect of breastfeeding compared to formula feeding nor the composition or quality of the complementary food. Possible short-term health effects concern growth velocity and infections, and possible long-term effects may relate to atopic diseases, type 1 and 2 diabetes, obesity and neuromuscular development. On the basis of the currently available evidence, it is impossible to exactly determine the age when risks related to the start of complementary feeding are lowest or highest for most of these effects, with the possible exception of infections and early growth velocity. The present knowledge on undesirable health effects, however, is mainly based on observational studies, and although some mechanisms have been proposed, further prospective studies have to clarify these unsolved issues. Even less evidence on the consequences of the timing of complementary food introduction is available for formula-fed infants. Copyright © 2012 S. Karger AG, Basel.

Comparative Evaluation of the Complementary and Alternative Medicine Therapy and Conventional Therapy Use for Musculoskeletal Disorders Management and Its Association with Job Satisfaction among Dentists of West India.

PubMed

Gupta, Devanand; Batra, Renu; Mahajan, Shveta; Bhaskar, Dara John; Jain, Ankita; Shiju, Mohammed; Yadav, Ankit; Chaturvedi, Mudita; Gill, Shruti; Verma, Renuka; Dalai, Deepak Ranjan; Gupta, Rajendra Kumar

2014-10-01

Musculoskeletal problems have become a significant issue in the profession of dentistry. There are currently no recommended effective disease-preventing and modifying remedies. High prevalence rates for musculoskeletal disorders (MSDs) among dentists have been reported in the literature. Complementary and alternative medicine can be helpful in managing and preventing the MSDs. The purpose of this study was to determine if dentists in the western part of India are using complementary and alternative medicine therapies for MSDs, and also to find if those who use complementary and alternative medicine therapies have greater job/career satisfaction compared to conventional therapy (CT) users. Dentists of western India registered under the Dental Council of India (N = 2166) were recruited for the study. Data were analyzed using univariate and bivariate analyses and logistic regression. A response rate of 73% (n = 1581) was obtained, of which 79% (n = 1249) was suffering from MSDs. The use of complementary and alternative medicine or CT was reported by 90% (n = 1124) of dentists with MSDs. Dentists using complementary and alternative medicine reported greater health (P < 0.001) and carrier satisfaction (P < 0.001) and were able to work as many hours they wanted (P < 0.001) compared to CT users. Complementary and alternative medicine therapies may improve the quality of life and enhance job satisfaction for a dentist who suffers from MSDs.

Women's motivation, perception and experience of complementary and alternative medicine in pregnancy: A meta-synthesis.

PubMed

Bowman, Rebekah L; Davis, Deborah L; Ferguson, Sally; Taylor, Jan

2018-04-01

complementary and Alternative Medicine use during pregnancy is popular in many countries, including Australia. There is currently little evidence to support this practice, which raises the question of women's motivation for use of these therapies and the experiences they encounter. this study aims to explore the perceptions, motivations and experiences of pregnant women with regard to their use of Complementary and Alternative Medicine during pregnancy. a systemic review and meta-synthesis of the available research was conducted. Five databases were explored - CINAHL Plus, Medline, PubMed, AMED and Web of Science using the search terms complementary and alternative medicine; pregnancy; and pregnant. Articles included in this meta-synthesis were screened using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses tool. ten initial themes were drawn from the six studies. These ten themes were summarised by three cluster themes. The results suggest that women are using Complementary and Alternative Medicine in their pregnancy as a means of supporting their sense of self-determination, to pursue a natural and safe childbirth, and because they experience a close affiliation with the philosophical underpinnings of Complementary and Alternative Medicine as an alternative to the biomedical model. these findings are important to practitioners, policy makers, governing bodies and researchers, providing insight into the motivations for Complementary and Alternative Medicine use by women in pregnancy. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Comparative Evaluation of the Complementary and Alternative Medicine Therapy and Conventional Therapy Use for Musculoskeletal Disorders Management and Its Association with Job Satisfaction among Dentists of West India

PubMed Central

Gupta, Devanand; Batra, Renu; Mahajan, Shveta; Bhaskar, Dara John; Jain, Ankita; Shiju, Mohammed; Yadav, Ankit; Chaturvedi, Mudita; Gill, Shruti; Verma, Renuka; Dalai, Deepak Ranjan; Gupta, Rajendra Kumar

2014-01-01

Musculoskeletal problems have become a significant issue in the profession of dentistry. There are currently no recommended effective disease-preventing and modifying remedies. High prevalence rates for musculoskeletal disorders (MSDs) among dentists have been reported in the literature. Complementary and alternative medicine can be helpful in managing and preventing the MSDs. The purpose of this study was to determine if dentists in the western part of India are using complementary and alternative medicine therapies for MSDs, and also to find if those who use complementary and alternative medicine therapies have greater job/career satisfaction compared to conventional therapy (CT) users. Dentists of western India registered under the Dental Council of India (N = 2166) were recruited for the study. Data were analyzed using univariate and bivariate analyses and logistic regression. A response rate of 73% (n = 1581) was obtained, of which 79% (n = 1249) was suffering from MSDs. The use of complementary and alternative medicine or CT was reported by 90% (n = 1124) of dentists with MSDs. Dentists using complementary and alternative medicine reported greater health (P < 0.001) and carrier satisfaction (P < 0.001) and were able to work as many hours they wanted (P < 0.001) compared to CT users. Complementary and alternative medicine therapies may improve the quality of life and enhance job satisfaction for a dentist who suffers from MSDs. PMID:25379469

Sexual reproduction and sex determination in green algae.

PubMed

Sekimoto, Hiroyuki

2017-05-01

The sexual reproductive processes of some representative freshwater green algae are reviewed. Chlamydomonas reinhardtii is a unicellular volvocine alga having two mating types: mating type plus (mt + ) and mating type minus (mt - ), which are controlled by a single, complex mating-type locus. Sexual adhesion between the gametes is mediated by sex-specific agglutinin molecules on their flagellar membranes. Cell fusion is initiated by an adhesive interaction between the mt + and mt - mating structures, followed by localized membrane fusion. The loci of sex-limited genes and the conformation of sex-determining regions have been rearranged during the evolution of volvocine algae; however, the essential function of the sex-determining genes of the isogamous unicellular Chlamydomonas reinhardtii is conserved in the multicellular oogamous Volvox carteri. The sexual reproduction of the unicellular charophycean alga, Closterium peracerosum-strigosum-littorale complex, is also focused on here. The sexual reproductive processes of heterothallic strains are controlled by two multifunctional sex pheromones, PR-IP and PR-IP Inducer, which independently promote multiple steps in conjugation at the appropriate times through different induction mechanisms. The molecules involved in sexual reproduction and sex determination have also been characterized.

The Price of Sex: Condom Use and the Determinants of the Price of Sex Among Female Sex Workers in Eastern Zimbabwe

PubMed Central

Elmes, Jocelyn; Nhongo, Kundai; Ward, Helen; Hallett, Timothy; Nyamukapa, Constance; White, Peter J.; Gregson, Simon

2014-01-01

Background. Higher prices for unprotected sex threaten the high levels of condom use that contributed to the decline in Zimbabwe's human immunodeficiency virus (HIV) epidemic. To improve understanding of financial pressures competing against safer sex, we explore factors associated with the price of commercial sex in rural eastern Zimbabwe. Methods. We collected and analyzed cross-sectional data on 311 women, recruited during October–December 2010, who reported that they received payment for their most-recent or second-most-recent sex acts in the past year. Zero-inflated negative binomial models with robust standard errors clustered on female sex worker (FSW) were used to explore social and behavioral determinants of price. Results. The median price of sex was $10 (interquartile range [IQR], $5–$20) per night and $10 (IQR, $5–$15) per act. Amounts paid in cash and commodities did not differ significantly. At the most-recent sex act, more-educated FSWs received 30%–74% higher payments. Client requests for condom use significantly predicted protected sex (P < .01), but clients paid on average 42.9% more for unprotected sex. Conclusions. Within a work environment where clients' preferences determine condom use, FSWs effectively use their individual capital to negotiate the terms of condom use. Strengthening FSWs' preferences for protected sex could help maintain high levels of condom use. PMID:25381377

Cardiac troponin T determination by a highly sensitive assay in postmortem serum and pericardial fluid.

PubMed

González-Herrera, Lucas; Valenzuela, Aurora; Ramos, Valentín; Blázquez, Antonia; Villanueva, Enrique

2016-06-01

The main objective of this study was to test, for the first time, a highly sensitive cardiac troponin T (cTnThs) assay in postmortem serum and pericardial fluid and to evaluate cardiac troponin T (cTnT) levels and their stability after death at different postmortem intervals, in an attempt to determine the viability of the cTnThs assay in the postmortem diagnosis of the cause of death. cTnT levels were determined in serum and pericardial fluid samples taken from 58 cadavers at known postmortem intervals, whose causes of death were categorized into the following groups: (1) sudden cardiac deaths, (2) multiple trauma, (3) mechanical asphyxia, and (4) other natural deaths. cTnT was determined by inmunoassay, using the Troponin T highly sensitive STAT assay (Roche(®)). Average cTnT levels measured by a highly sensitive assay in postmortem serum were markedly higher than clinical serum levels. Moreover, similar results, higher cTnT levels in postmortem pericardial fluid, were obtained when compared to levels found in pericardial fluid taken from two living patients during coronary artery bypass surgery. cTnT levels in both postmortem fluids remained stable for up to 34 h after death. No differences in cTnT levels in either postmortem fluid by sex and age were detected. Levels of cTnT found in pericardial fluid in the other natural deaths group were significantly lower than the cTnT levels found in that postmortem fluid from any of the other causes of death groups. It is therefore reasonable to conclude that determination of cTnT by a highly sensitive assay in pericardial fluid can provide forensic pathologists with a complementary test to the diagnosis of cause of death.

Sexy splicing: regulatory interplays governing sex determination from Drosophila to mammals.

PubMed

Lalli, Enzo; Ohe, Kenji; Latorre, Elisa; Bianchi, Marco E; Sassone-Corsi, Paolo

2003-02-01

A remarkable array of strategies is used to produce sexual differentiation in different species. Complex gene hierarchies govern sex determination pathways, as exemplified by the classic D. melanogaster paradigm, where an interplay of transcriptional, splicing and translational mechanisms operate. Molecular studies support the hypothesis that genetic sex determination pathways evolved in reverse order, from downstream to upstream genes, in the cascade. The recent identification of a role for the key regulatory factors SRY and WT1(+KTS) in pre-mRNA splicing indicates that important steps in the mammalian sex determination process are likely to operate at the post-transcriptional level.

Sexing the Sciuridae: a simple and accurate set of molecular methods to determine sex in tree squirrels, ground squirrels and marmots.

PubMed

Gorrell, Jamieson C; Boutin, Stan; Raveh, Shirley; Neuhaus, Peter; Côté, Steeve D; Coltman, David W

2012-09-01

We determined the sequence of the male-specific minor histocompatibility complex antigen (Smcy) from the Y chromosome of seven squirrel species (Sciuridae, Rodentia). Based on conserved regions inside the Smcy intron sequence, we designed PCR primers for sex determination in these species that can be co-amplified with nuclear loci as controls. PCR co-amplification yields two products for males and one for females that are easily visualized as bands by agarose gel electrophoresis. Our method provides simple and reliable sex determination across a wide range of squirrel species. © 2012 Blackwell Publishing Ltd.

ZNRF3 functions in mammalian sex determination by inhibiting canonical WNT signaling.

PubMed

Harris, Abigail; Siggers, Pam; Corrochano, Silvia; Warr, Nick; Sagar, Danielle; Grimes, Daniel T; Suzuki, Makoto; Burdine, Rebecca D; Cong, Feng; Koo, Bon-Kyoung; Clevers, Hans; Stévant, Isabelle; Nef, Serge; Wells, Sara; Brauner, Raja; Ben Rhouma, Bochra; Belguith, Neïla; Eozenou, Caroline; Bignon-Topalovic, Joelle; Bashamboo, Anu; McElreavey, Ken; Greenfield, Andy

2018-05-22

Mammalian sex determination is controlled by the antagonistic interactions of two genetic pathways: The SRY-SOX9-FGF9 network promotes testis determination partly by opposing proovarian pathways, while RSPO1/WNT-β-catenin/FOXL2 signals control ovary development by inhibiting SRY-SOX9-FGF9. The molecular basis of this mutual antagonism is unclear. Here we show that ZNRF3, a WNT signaling antagonist and direct target of RSPO1-mediated inhibition, is required for sex determination in mice. XY mice lacking ZNRF3 exhibit complete or partial gonadal sex reversal, or related defects. These abnormalities are associated with ectopic WNT/β-catenin activity and reduced Sox9 expression during fetal sex determination. Using exome sequencing of individuals with 46,XY disorders of sex development, we identified three human ZNRF3 variants in very rare cases of XY female presentation. We tested two missense variants and show that these disrupt ZNRF3 activity in both human cell lines and zebrafish embryo assays. Our data identify a testis-determining function for ZNRF3 and indicate a mechanism of direct molecular interaction between two mutually antagonistic organogenetic pathways. Copyright © 2018 the Author(s). Published by PNAS.

Dimorphic DNA methylation during temperature-dependent sex determination in the sea turtle Lepidochelys olivacea.

PubMed

Venegas, Daniela; Marmolejo-Valencia, Alejandro; Valdes-Quezada, Christian; Govenzensky, Tzipe; Recillas-Targa, Félix; Merchant-Larios, Horacio

2016-09-15

Sex determination in vertebrates depends on the expression of a conserved network of genes. Sea turtles such as Lepidochelys olivacea have temperature-dependent sex determination. The present work analyses some of the epigenetic processes involved in this. We describe sexual dimorphism in global DNA methylation patterns between ovaries and testes of L. olivacea and show that the differences may arise from a combination of DNA methylation and demethylation events that occur during sex determination. Irrespective of incubation temperature, 5-hydroxymethylcytosine was abundant in the bipotential gonad; however, following sex determination, this modification was no longer found in pre-Sertoli cells in the testes. These changes correlate with the establishment of the sexually dimorphic DNA methylation patterns, down regulation of Sox9 gene expression in ovaries and irreversible gonadal commitment towards a male or female differentiation pathway. Thus, DNA methylation changes may be necessary for the stabilization of the gene expression networks that drive the differentiation of the bipotential gonad to form either an ovary or a testis in L. olivacea and probably among other species that manifest temperature-dependent sex determination. Copyright © 2016 Elsevier Inc. All rights reserved.

Molecular characterization and evolutionary insights into potential sex-determination genes in the western orchard predatory mite Metaseiulus occidentalis (Chelicerata: Arachnida: Acari: Phytoseiidae).

PubMed

Pomerantz, Aaron F; Hoy, Marjorie A; Kawahara, Akito Y

2015-01-01

Little is known about the process of sex determination at the molecular level in species belonging to the subclass Acari, a taxon of arachnids that contains mites and ticks. The recent sequencing of the transcriptome and genome of the western orchard predatory mite Metaseiulus occidentalis allows investigation of molecular mechanisms underlying the biological processes of sex determination in this predator of phytophagous pest mites. We identified four doublesex-and-mab-3-related transcription factor (dmrt) genes, one transformer-2 gene, one intersex gene, and two fruitless-like genes in M. occidentalis. Phylogenetic analyses were conducted to infer the molecular relationships to sequences from species of arthropods, including insects, crustaceans, acarines, and a centipede, using available genomic data. Comparative analyses revealed high sequence identity within functional domains and confirmed that the architecture for certain sex-determination genes is conserved in arthropods. This study provides a framework for identifying potential target genes that could be implicated in the process of sex determination in M. occidentalis and provides insight into the conservation and change of the molecular components of sex determination in arthropods.

ZNRF3 functions in mammalian sex determination by inhibiting canonical WNT signaling

PubMed Central

Harris, Abigail; Siggers, Pam; Warr, Nick; Sagar, Danielle; Grimes, Daniel T.; Cong, Feng; Koo, Bon-Kyoung; Clevers, Hans; Stévant, Isabelle; Nef, Serge; Wells, Sara; Brauner, Raja; Ben Rhouma, Bochra; Belguith, Neïla; Eozenou, Caroline; Bignon-Topalovic, Joelle; Bashamboo, Anu; McElreavey, Ken

2018-01-01

Mammalian sex determination is controlled by the antagonistic interactions of two genetic pathways: The SRY-SOX9-FGF9 network promotes testis determination partly by opposing proovarian pathways, while RSPO1/WNT-β-catenin/FOXL2 signals control ovary development by inhibiting SRY-SOX9-FGF9. The molecular basis of this mutual antagonism is unclear. Here we show that ZNRF3, a WNT signaling antagonist and direct target of RSPO1-mediated inhibition, is required for sex determination in mice. XY mice lacking ZNRF3 exhibit complete or partial gonadal sex reversal, or related defects. These abnormalities are associated with ectopic WNT/β-catenin activity and reduced Sox9 expression during fetal sex determination. Using exome sequencing of individuals with 46,XY disorders of sex development, we identified three human ZNRF3 variants in very rare cases of XY female presentation. We tested two missense variants and show that these disrupt ZNRF3 activity in both human cell lines and zebrafish embryo assays. Our data identify a testis-determining function for ZNRF3 and indicate a mechanism of direct molecular interaction between two mutually antagonistic organogenetic pathways. PMID:29735715

The role of estrogen in turtle sex determination and the effect of PCBs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crews, D.; Bergeron, J.M.; McLachlan, J.A.

1995-10-01

Gonadal sex is fixed at fertilization by specific chromosomes, a process known as genotypic sex determination (GSD). Only after the gonad is formed do hormones begin to exert an influence that modifies specific structures that eventually will differ between the sexes. Many egg-laying reptiles do not exhibit GSD but rather depend on the temperature of the incubating egg to determine the gonadal sex of the offspring, a process termed temperature-dependent sex determination (TSD). Research on TSD indicates that gonadal sex is not irrevocably set by the genetic composition inherited at fertilization but depends ultimately on which genes encoding for steroidogenicmore » enzymes and hormone receptors are activated during the midtrimester of embryonic development by temperature. Incubation temperature modifies the activity as well as the temporal and spatial sequence of enzymes and hormone receptors to determine gonad type. Estrogen is the physiologic equivalent of incubation temperature and the proximate cue that initiates female sex determination. increasing evidence indicates some polychlorinated biphenyl (PCB) compounds are capable of disrupting reproductive and endocrine function in fish, birds, and mammals, including humans. Reproductive disorders resulting from exposure to these xenobiotic compounds may include reductions in fertility, hatch rate in fish and birds, and viability of offspring, as well as alterations in hormone levels or adult sexual behaviors. Research on the mechanism through which these compounds may be acting to alter reproductive function indicates estrogenic activity, by which the compounds may be altering sexual differentiation. In TSD turtles, the estrogenic effect of some PCBs reverses gonadal sex in individuals incubating at an otherwise male-producing temperature. Furthermore, certain PCBs are synergistic in their effect at very low concentrations. 19 refs., 3 figs., 1 tab.« less

Allelic incompatibility can explain female biased sex ratios in dioecious plants.

PubMed

Pucholt, Pascal; Hallingbäck, Henrik R; Berlin, Sofia

2017-03-23

Biased sex ratios are common among dioecious plant species despite the theoretical prediction of selective advantage of even sex ratios. Albeit the high prevalence of deviations from even sex ratios, the genetic causes to sex biases are rarely known outside of a few model species. Here we present a mechanism underlying the female biased sex ratio in the dioecious willow species Salix viminalis. We compared the segregation pattern of genome-wide single nucleotide polymorphism markers in two contrasting bi-parental pedigree populations, the S3 with even sex ratio and the S5 with a female biased sex ratio. With the segregation analysis and comparison between the two populations, we were able to demonstrate that sex determination and sex ratio distortion are controlled by different genetic mechanisms. We furthermore located the sex ratio distorter locus to a Z/W-gametologous region on chromosome 15, which was in close linkage with the sex determination locus. Interestingly, all males in the population with biased sex ratio have in this sex ratio distorter locus the same genotype, meaning that males with the Z 1 /Z 3 -genotype were missing from the population, thereby creating the 2:1 female biased sex ratio. We attribute the absence of Z 1 /Z 3 males to an allelic incompatibility between maternally and paternally inherited alleles in this sex ratio distorter locus. Due to the tight linkage with the sex determination locus only male individuals are purged from the population at an early age, presumably before or during seed development. We showed that such allelic incompatibility could be stably maintained over evolutionary times through a system of overdominant or pseudooverdominant alleles. Thus, it is possible that the same mechanism generates the female biased sex ratio in natural willow populations.

Bombyx mori P-element Somatic Inhibitor (BmPSI) Is a Key Auxiliary Factor for Silkworm Male Sex Determination

PubMed Central

Chen, Shuqing; Zeng, Baosheng; James, Anthony A.; Tan, Anjiang; Huang, Yongping

2017-01-01

Manipulation of sex determination pathways in insects provides the basis for a wide spectrum of strategies to benefit agriculture and public health. Furthermore, insects display a remarkable diversity in the genetic pathways that lead to sex differentiation. The silkworm, Bombyx mori, has been cultivated by humans as a beneficial insect for over two millennia, and more recently as a model system for studying lepidopteran genetics and development. Previous studies have identified the B. mori Fem piRNA as the primary female determining factor and BmMasc as its downstream target, while the genetic scenario for male sex determination was still unclear. In the current study, we exploite the transgenic CRISPR/Cas9 system to generate a comprehensive set of knockout mutations in genes BmSxl, Bmtra2, BmImp, BmImpM, BmPSI and BmMasc, to investigate their roles in silkworm sex determination. Absence of Bmtra2 results in the complete depletion of Bmdsx transcripts, which is the conserved downstream factor in the sex determination pathway, and induces embryonic lethality. Loss of BmImp or BmImpM function does not affect the sexual differentiation. Mutations in BmPSI and BmMasc genes affect the splicing of Bmdsx and the female reproductive apparatus appeared in the male external genital. Intriguingly, we identify that BmPSI regulates expression of BmMasc, BmImpM and Bmdsx, supporting the conclusion that it acts as a key auxiliary factor in silkworm male sex determination. PMID:28103247

Sex determination of ovine embryos by SRY and amelogenin (AMEL) genes using maternal circulating cell free DNA.

PubMed

Saberivand, Adel; Ahsan, Sima

2016-01-01

Simple and precise methods for sex determination in animals are a pre-requisite for a number of applications in animal production and forensics. Some of the existing methods depend only on the detection of Y-chromosome specific sequences. However, the detection of Y and X-chromosome specific sequences is advantageous. In the present study the accuracy of sex determination by SRY (sex-determining region Y) and AMEL (Amelogenin) gene detection was assessed using a polymerase chain reaction (PCR) of DNA extracted from free fetal cells in maternal blood, which is noninvasive for fetus and easier to collect. The PCR amplification of SRY primers produced a single band of 171bp from ewes bearing a male fetus, whereas no band was amplified from the DNA extracted from ewes pregnant to a female fetus. Moreover, two bands of 182 and 242bp in male and a single band of 242 in female fetuses were produced by AMEL gene primers in the PCR reaction. Using this technique 100% of samples were successfully sexed, excluding twins. In conclusion, we demonstrated that sex determination using DNA of free fetal cells in maternal plasma is efficient using both SRY and AMEL gene sequences. It also is evident that this method is not suitable for sex determination of twin pregnancies. Copyright © 2015 Elsevier B.V. All rights reserved.

Occupational Segregation by Sex: Determinants and Changes.

ERIC Educational Resources Information Center

Beller, Andrea H.

1982-01-01

This study found that occupational sex segregation began to diminish during the 1970s, in conjunction with enforcement of the equal employment opportunity laws against sex discrimination in employment. The success of these laws suggests that discrimination was originally a determinant of occupational segregation. (Author/SK)

Assessment of craniometric traits in South Indian dry skulls for sex determination.

PubMed

Ramamoorthy, Balakrishnan; Pai, Mangala M; Prabhu, Latha V; Muralimanju, B V; Rai, Rajalakshmi

2016-01-01

The skeleton plays an important role in sex determination in forensic anthropology. The skull bone is considered as the second best after the pelvic bone in sex determination due to its better retention of morphological features. Different populations have varying skeletal characteristics, making population specific analysis for sex determination essential. Hence the objective of this investigation is to obtain the accuracy of sex determination using cranial parameters of adult skulls to the highest percentage in South Indian population and to provide a baseline data for sex determination in South India. Seventy adult preserved human skulls were taken and based on the morphological traits were classified into 43 male skulls and 27 female skulls. A total of 26 craniometric parameters were studied. The data were analyzed by using the SPSS discriminant function. The analysis of stepwise, multivariate, and univariate discriminant function gave an accuracy of 77.1%, 85.7%, and 72.9% respectively. Multivariate direct discriminant function analysis classified skull bones into male and female with highest levels of accuracy. Using stepwise discriminant function analysis, the most dimorphic variable to determine sex of the skull, was biauricular breadth followed by weight. Subjecting the best dimorphic variables to univariate discriminant analysis, high levels of accuracy of sexual dimorphism was obtained. Percentage classification of high accuracies were obtained in this study indicating high level of sexual dimorphism in the crania, setting specific discriminant equations for the gender determination in South Indian people. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Evolutionary Significance of Wolbachia-to-Animal Horizontal Gene Transfer: Female Sex Determination and the f Element in the Isopod Armadillidium vulgare.

PubMed

Cordaux, Richard; Gilbert, Clément

2017-07-21

An increasing number of horizontal gene transfer (HGT) events from bacteria to animals have been reported in the past years, many of which involve Wolbachia bacterial endosymbionts and their invertebrate hosts. Most transferred Wolbachia genes are neutrally-evolving fossils embedded in host genomes. A remarkable case of Wolbachia HGT for which a clear evolutionary significance has been demonstrated is the " f element", a nuclear Wolbachia insert involved in female sex determination in the terrestrial isopod Armadillidium vulgare . The f element represents an instance of bacteria-to-animal HGT that has occurred so recently that it was possible to infer the donor (feminizing Wolbachia closely related to the w VulC Wolbachia strain of A. vulgare ) and the mechanism of integration (a nearly complete genome inserted by micro-homology-mediated recombination). In this review, we summarize our current knowledge of the f element and discuss arising perspectives regarding female sex determination, unstable inheritance, population dynamics and the molecular evolution of the f element. Overall, the f element unifies three major areas in evolutionary biology: symbiosis, HGT and sex determination. Its characterization highlights the tremendous impact sex ratio distorters can have on the evolution of sex determination mechanisms and sex chromosomes in animals and plants.

Sex determination from the talus in a contemporary Greek population using discriminant function analysis.

PubMed

Peckmann, Tanya R; Orr, Kayla; Meek, Susan; Manolis, Sotiris K

2015-07-01

The determination of sex is an important part of building the biological profile for unknown human remains. Many of the bones traditionally used for the determination of sex are often found fragmented or incomplete in forensic and archaeological cases. The goal of the present research was to derive discriminant function equations from the talus, a preservationally favoured bone, for sexing skeletons from a contemporary Greek population. Nine parameters were measured on 182 individuals (96 males and 86 females) from the University of Athens Human Skeletal Reference Collection. The individuals ranged in age from 20 to 99 years old. The statistical analyses showed that all measured parameters were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 65.2% to 93.4% for the univariate analysis, 90%-96.5% for the direct method and 86.7% for the stepwise method. Comparisons to other populations were made. Overall, the cross-validated accuracies ranged from 65.5% to 83.2% and males were most often correctly identified. The talus was shown to be useful for sex determination in the modern Greek population. Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

Paternal Genome Elimination in Liposcelis Booklice (Insecta: Psocodea)

PubMed Central

Hodson, Christina N.; Hamilton, Phineas T.; Dilworth, Dave; Nelson, Chris J.; Curtis, Caitlin I.; Perlman, Steve J.

2017-01-01

How sex is determined in insects is diverse and dynamic, and includes male heterogamety, female heterogamety, and haplodiploidy. In many insect lineages, sex determination is either completely unknown or poorly studied. We studied sex determination in Psocodea—a species-rich order of insects that includes parasitic lice, barklice, and booklice. We focus on a recently discovered species of Liposcelis booklice (Psocodea: Troctomorpha), which are among the closest free-living relatives of parasitic lice. Using genetic, genomic, and immunohistochemical approaches, we show that this group exhibits paternal genome elimination (PGE), an unusual mode of sex determination that involves genomic imprinting. Controlled crosses, following a genetic marker over multiple generations, demonstrated that males only transmit to offspring genes they inherited from their mother. Immunofluorescence microscopy revealed densely packed chromocenters associated with H3K9me3—a conserved marker for heterochromatin—in males, but not in females, suggesting silencing of chromosomes in males. Genome assembly and comparison of read coverage in male and female libraries showed no evidence for differentiated sex chromosomes. We also found that females produce more sons early in life, consistent with facultative sex allocation. It is likely that PGE is widespread in Psocodea, including human lice. This order represents a promising model for studying this enigmatic mode of sex determination. PMID:28292917

Cytogenetic Insights into the Evolution of Chromosomes and Sex Determination Reveal Striking Homology of Turtle Sex Chromosomes to Amphibian Autosomes.

PubMed

Montiel, Eugenia E; Badenhorst, Daleen; Lee, Ling S; Literman, Robert; Trifonov, Vladimir; Valenzuela, Nicole

2016-01-01

Turtle karyotypes are highly conserved compared to other vertebrates; yet, variation in diploid number (2n = 26-68) reflects profound genomic reorganization, which correlates with evolutionary turnovers in sex determination. We evaluate the published literature and newly collected comparative cytogenetic data (G- and C-banding, 18S-NOR, and telomere-FISH mapping) from 13 species spanning 2n = 28-68 to revisit turtle genome evolution and sex determination. Interstitial telomeric sites were detected in multiple lineages that underwent diploid number and sex determination turnovers, suggesting chromosomal rearrangements. C-banding revealed potential interspecific variation in centromere composition and interstitial heterochromatin at secondary constrictions. 18S-NORs were detected in secondary constrictions in a single chromosomal pair per species, refuting previous reports of multiple NORs in turtles. 18S-NORs are linked to ZW chromosomes in Apalone and Pelodiscus and to X (not Y) in Staurotypus. Notably, comparative genomics across amniotes revealed that the sex chromosomes of several turtles, as well as mammals and some lizards, are homologous to components of Xenopus tropicalis XTR1 (carrying Dmrt1). Other turtle sex chromosomes are homologous to XTR4 (carrying Wt1). Interestingly, all known turtle sex chromosomes, except in Trionychidae, evolved via inversions around Dmrt1 or Wt1. Thus, XTR1 appears to represent an amniote proto-sex chromosome (perhaps linked ancestrally to XTR4) that gave rise to turtle and other amniote sex chromosomes. © 2016 S. Karger AG, Basel.

Karyotype analysis and sex determination in Australian Brush-turkeys (Alectura lathami).

PubMed

Ortega, Madison T; Foote, Dustin J; Nees, Nicholas; Erdmann, Jason C; Bangs, Charles D; Rosenfeld, Cheryl S

2017-01-01

Sexual differentiation across taxa may be due to genetic sex determination (GSD) and/or temperature sex determination (TSD). In many mammals, males are heterogametic (XY); whereas females are homogametic (XX). In most birds, the opposite is the case with females being heterogametic (ZW) and males the homogametic sex (ZZ). Many reptile species lack sex chromosomes, and instead, sexual differentiation is influenced by temperature with specific temperatures promoting males or females varying across species possessing this form of sexual differentiation, although TSD has recently been shown to override GSD in Australian central beaded dragons (Pogona vitticeps). There has been speculation that Australian Brush-turkeys (Alectura lathami) exhibit TSD alone and/or in combination with GSD. Thus, we sought to determine if this species possesses sex chromosomes. Blood was collected from one sexually mature female and two sexually mature males residing at Sylvan Heights Bird Park (SHBP) and shipped for karyotype analysis. Karyotype analysis revealed that contrary to speculation, Australian Brush-turkeys possess the classic avian ZW/ZZ sex chromosomes. It remains a possibility that a biased primary sex ratio of Australian Brush-turkeys might be influenced by maternal condition prior to ovulation that result in her laying predominantly Z- or W-bearing eggs and/or sex-biased mortality due to higher sensitivity of one sex in environmental conditions. A better understanding of how maternal and extrinsic factors might differentially modulate ovulation of Z- or W-bearing eggs and hatching of developing chicks possessing ZW or ZZ sex chromosomes could be essential in conservation strategies used to save endangered members of Megapodiidae.

Karyotype analysis and sex determination in Australian Brush-turkeys (Alectura lathami)

PubMed Central

Ortega, Madison T.; Foote, Dustin J.; Nees, Nicholas; Erdmann, Jason C.; Bangs, Charles D.

2017-01-01

Sexual differentiation across taxa may be due to genetic sex determination (GSD) and/or temperature sex determination (TSD). In many mammals, males are heterogametic (XY); whereas females are homogametic (XX). In most birds, the opposite is the case with females being heterogametic (ZW) and males the homogametic sex (ZZ). Many reptile species lack sex chromosomes, and instead, sexual differentiation is influenced by temperature with specific temperatures promoting males or females varying across species possessing this form of sexual differentiation, although TSD has recently been shown to override GSD in Australian central beaded dragons (Pogona vitticeps). There has been speculation that Australian Brush-turkeys (Alectura lathami) exhibit TSD alone and/or in combination with GSD. Thus, we sought to determine if this species possesses sex chromosomes. Blood was collected from one sexually mature female and two sexually mature males residing at Sylvan Heights Bird Park (SHBP) and shipped for karyotype analysis. Karyotype analysis revealed that contrary to speculation, Australian Brush-turkeys possess the classic avian ZW/ZZ sex chromosomes. It remains a possibility that a biased primary sex ratio of Australian Brush-turkeys might be influenced by maternal condition prior to ovulation that result in her laying predominantly Z- or W-bearing eggs and/or sex-biased mortality due to higher sensitivity of one sex in environmental conditions. A better understanding of how maternal and extrinsic factors might differentially modulate ovulation of Z- or W-bearing eggs and hatching of developing chicks possessing ZW or ZZ sex chromosomes could be essential in conservation strategies used to save endangered members of Megapodiidae. PMID:28910392

Sex ratio selection and multi-factorial sex determination in the housefly: a dynamic model.

PubMed

Kozielska, M; Pen, I; Beukeboom, L W; Weissing, F J

2006-05-01

Sex determining (SD) mechanisms are highly variable between different taxonomic groups and appear to change relatively quickly during evolution. Sex ratio selection could be a dominant force causing such changes. We investigate theoretically the effect of sex ratio selection on the dynamics of a multi-factorial SD system. The system considered resembles the naturally occurring three-locus system of the housefly, which allows for male heterogamety, female heterogamety and a variety of other mechanisms. Sex ratio selection is modelled by assuming cost differences in the production of sons and daughters, a scenario leading to a strong sex ratio bias in the absence of constraints imposed by the mechanism of sex determination. We show that, despite of the presumed flexibility of the SD system considered, equilibrium sex ratios never deviate strongly from 1 : 1. Even if daughters are very costly, a male-biased sex ratio can never evolve. If sons are more costly, sex ratio can be slightly female biased but even in case of large cost differences the bias is very small (<10% from 1 : 1). Sex ratio selection can lead to a shift in the SD mechanism, but cannot be the sole cause of complete switches from one SD system to another. In fact, more than one locus remains polymorphic at equilibrium. We discuss our results in the context of evolution of the variable SD mechanism found in natural housefly populations.

Temperature-dependent sex determination in fish revisited: prevalence, a single sex ratio response pattern, and possible effects of climate change.

PubMed

Ospina-Alvarez, Natalia; Piferrer, Francesc

2008-07-30

In gonochoristic vertebrates, sex determination mechanisms can be classified as genotypic (GSD) or temperature-dependent (TSD). Some cases of TSD in fish have been questioned, but the prevalent view is that TSD is very common in this group of animals, with three different response patterns to temperature. We analyzed field and laboratory data for the 59 fish species where TSD has been explicitly or implicitly claimed so far. For each species, we compiled data on the presence or absence of sex chromosomes and determined if the sex ratio response was obtained within temperatures that the species experiences in the wild. If so, we studied whether this response was statistically significant. We found evidence that many cases of observed sex ratio shifts in response to temperature reveal thermal alterations of an otherwise predominately GSD mechanism rather than the presence of TSD. We also show that in those fish species that actually have TSD, sex ratio response to increasing temperatures invariably results in highly male-biased sex ratios, and that even small changes of just 1-2 degrees C can significantly alter the sex ratio from 1:1 (males:females) up to 3:1 in both freshwater and marine species. We demonstrate that TSD in fish is far less widespread than currently believed, suggesting that TSD is clearly the exception in fish sex determination. Further, species with TSD exhibit only one general sex ratio response pattern to temperature. However, the viability of some fish populations with TSD can be compromised through alterations in their sex ratios as a response to temperature fluctuations of the magnitude predicted by climate change.

A neo-sex-chromosome that drives post-zygotic sex determiniation in the Hessian fly

USDA-ARS?s Scientific Manuscript database

Two nonoverlapping autosomal inversions defined unusual neo-sex chromosomes in the Hessian fly (Mayetiola destructor). Like other neo-sex chromosomes, these were normally heterozygous, present only in one sex, and suppressed recombination around a sex-determining master switch. Their unusual propert...

Acceptability of vaginal microbicides among female sex workers and their intimate male partners in two Mexico-US border cities: a mixed methods analysis.

PubMed

Robertson, Angela M; Syvertsen, Jennifer L; Martinez, Gustavo; Rangel, M Gudelia; Palinkas, Lawrence A; Stockman, Jamila K; Ulibarri, Monica D; Strathdee, Steffanie A

2013-01-01

Female sex workers (FSWs) may benefit from pre-exposure prophylaxis (PrEP) including microbicides for HIV prevention. Since adherence is a key factor in PrEP efficacy, we explored microbicide acceptability and potential barriers to use within FSWs' intimate relationships in Tijuana and Ciudad Juárez, Mexico, where HIV prevalence is increasing. FSWs and their verified intimate (non-commercial) male partners completed quantitative and qualitative interviews from 2010 to 2012. Our complementary mixed methods design followed an iterative process to assess microbicide acceptability, explore related relationship dynamics and identify factors associated with concern about male partners' anger regarding microbicide use. Among 185 couples (n=370 individuals), interest in microbicides was high. In qualitative interviews with 28 couples, most participants were enthusiastic about microbicides for sex work contexts but some explained that microbicides could imply mistrust/infidelity within their intimate relationships. In the overall sample, nearly one in six participants (16%) worried that male partners would become angry about microbicides, which was associated with higher self-esteem among FSWs and lower self-esteem and past year conflicts causing injury within relationships among men. HIV prevention interventions should consider intimate relationship dynamics posing potential barriers to PrEP acceptability and adherence, involve male partners and promote risk communication skills.

Characterisation of ATRX, DMRT1, DMRT7 and WT1 in the platypus (Ornithorhynchus anatinus).

PubMed

Tsend-Ayush, Enkhjargal; Lim, Shu Ly; Pask, Andrew J; Hamdan, Diana Demiyah Mohd; Renfree, Marilyn B; Grützner, Frank

2009-01-01

One of the most puzzling aspects of monotreme reproductive biology is how they determine sex in the absence of the SRY gene that triggers testis development in most other mammals. Although monotremes share a XX female/XY male sex chromosome system with other mammals, their sex chromosomes show homology to the chicken Z chromosome, including the DMRT1 gene, which is a dosage-dependent sex determination gene in birds. In addition, monotremes feature an extraordinary multiple sex chromosome system. However, no sex determination gene has been identified as yet on any of the five X or five Y chromosomes and there is very little knowledge about the conservation and function of other known genes in the monotreme sex determination and differentiation pathway. We have analysed the expression pattern of four evolutionarily conserved genes that are important at different stages of sexual development in therian mammals. DMRT1 is a conserved sex-determination gene that is upregulated in the male developing gonad in vertebrates, while DMRT7 is a mammal-specific spermatogenesis gene. ATRX, a chromatin remodelling protein, lies on the therian X but there is a testis-expressed Y-copy in marsupials. However, in monotremes, the ATRX orthologue is autosomal. WT1 is an evolutionarily conserved gene essential for early gonadal formation in both sexes and later in testis development. We show that these four genes in the adult platypus have the same expression pattern as in other mammals, suggesting that they have a conserved role in sexual development independent of genomic location.

Decision Processes During Development of Molecular Biomarkers for Gonadal Phenotypic Sex

EPA Science Inventory

Molecular biomarkers for determination of gonadal phenotypic sex in the Japanese medaka (Oryzias latipes), will serve as a case study. The medaka has unique features that aid in the development of appropriate molecular biomarkers of gonad phenotype, a) genetic sex can be determin...

Maternal provision of transformer-2 is required for female development and embryo viability in the wasp Nasonia vitripennis.

PubMed

Geuverink, Elzemiek; Rensink, Anna H; Rondeel, Inge; Beukeboom, Leo W; van de Zande, Louis; Verhulst, Eveline C

2017-11-01

In insect sex determination a primary signal starts the genetic sex determination cascade that, in most insect orders, is subsequently transduced down the cascade by a transformer (tra) ortholog. Only a female-specifically spliced tra mRNA yields a functional TRA-protein that forms a complex with TRA2, encoded by a transformer-2 (tra2) ortholog, to act as a sex specific splicing regulator of the downstream transcription factors doublesex (dsx) and fruitless (fru). Here, we identify the tra2 ortholog of the haplodiploid parasitoid wasp N. vitripennis (Nv-tra2) and confirm its function in N. vitripennis sex determination. Knock down of Nv-tra2 by parental RNA interference (pRNAi) results in complete sex reversal of diploid offspring from female to male, indicating the requirement of Nv-tra2 for female sex determination. As Nv-tra2 pRNAi leads to frequent lethality in early developmental stages, maternal provision of Nv-tra2 transcripts is apparently also required for another, non-sex determining function during embryogenesis. In addition, lethality following Nv-tra2 pRNAi appears more pronounced in diploid than in haploid offspring. This diploid lethal effect was also observed following Nv-tra pRNAi, which served as a positive control in our experiments. As diploid embryos from fertilized eggs have a paternal chromosome set in addition to the maternal one, this suggests that either the presence of this paternal chromosome set or the dosage effect resulting from the diploid state is incompatible with the induced male development in N. vitripennis caused by either Nv-tra2 or Nv-tra pRNAi. The role of Nv-tra2 in activating the female sex determination pathway yields more insight into the sex determination mechanism of Nasonia. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Sex-Specific Genetic Loci for Femoral Neck Bone Mass and Strength Identified in Inbred COP and DA Rats

PubMed Central

Alam, Imranul; Sun, Qiwei; Liu, Lixiang; Koller, Daniel L; Carr, Lucinda G; Econs, Michael J; Foroud, Tatiana; Turner, Charles H

2008-01-01

Introduction Hip fracture is the most devastating osteoporotic fracture type with significant morbidity and mortality. Several studies in humans identified chromosomal regions linked to hip size and bone mass. Animal models, particularly the inbred rat, serve as complementary approaches for studying the genetic influence on hip fragility. The purpose of this study is to identify sex-independent and sex-specific quantitative trait loci (QTLs) for femoral neck density, structure, and strength in inbred Copenhagen 2331 (COP) and Dark Agouti (DA) rats. Materials and Methods A total of 828 (405 males and 423 females) F2 progeny derived from the inbred COP and DA strains of rats were phenotyped for femoral neck volumetric BMD (vBMD), cross-sectional area, polar moment of inertia (Ip), neck width, ultimate force, and energy to break. A whole genome screen was performed using 93 microsatellite markers with an average intermarker distance of 20 cM. Recombination-based marker maps were generated using MAPMAKER/EXP from the COP × DA F2 data and compared with published Rat Genome Database (RGD) maps. These maps were used for genome-wide linkage analyses to detect sex-independent and sex-specific QTLs. Results Significant evidence of linkage (p < 0.01) for sex-independent QTLs were detected for (1) femoral neck vBMD on chromosomes (Chrs) 1, 6, 10, and 12, (2) femoral neck structure on Chrs 5, 7, 10, and 18, and (3) biomechanical properties on Chrs 1 and 4. Male-specific QTLs were discovered on Chrs 2, 9, and 18 for total vBMD, on Chr 17 for trabecular vBMD, on Chr 9 for total bone area, and on Chr 15 for ultimate force. A female-specific QTL was discovered on Chr 2 for ultimate force. The effect size of the individual QTL varied between 1% and 4%. Conclusions We detected evidence that sex-independent and sex-specific QTLs contribute to hip fragility in the inbred rat. Several QTLs regions identified in this study are homologous to human chromosomal regions previously linked to QTLs contributing to femoral neck and related phenotypes. PMID:18282130

Male sexual dysfunction in Asia

PubMed Central

Ho, Christopher CK; Singam, Praveen; Hong, Goh Eng; Zainuddin, Zulkifli Md

2011-01-01

Sex has always been a taboo subject in Asian society. However, over the past few years, awareness in the field of men's sexual health has improved, and interest in sexual health research has recently increased. The epidemiology and prevalence of erectile dysfunction, hypogonadism and premature ejaculation in Asia are similar in the West. However, several issues are specific to Asian males, including culture and beliefs, awareness, compliance and the availability of traditional/complementary medicine. In Asia, sexual medicine is still in its infancy, and a concerted effort from the government, relevant societies, physicians and the media is required to propel sexual medicine to the forefront of health care. PMID:21643001

Are some chromosomes particularly good at sex? Insights from amniotes.

PubMed

O'Meally, Denis; Ezaz, Tariq; Georges, Arthur; Sarre, Stephen D; Graves, Jennifer A Marshall

2012-01-01

Several recent studies have produced comparative maps of genes on amniote sex chromosomes, revealing homology of gene content and arrangement across lineages as divergent as mammals and lizards. For example, the chicken Z chromosome, which shares homology with the sex chromosomes of all birds, monotremes, and a gecko, is a striking example of stability of genome organization and retention, or independent acquisition, of function in sex determination. In other lineages, such as snakes and therian mammals, well conserved but independently evolved sex chromosome systems have arisen. Among lizards, novel sex chromosomes appear frequently, even in congeneric species. Here, we review recent gene mapping data, examine the evolutionary relationships of amniote sex chromosomes and argue that gene content can predispose some chromosomes to a specialized role in sex determination.

The effects of temperature on sex determination in the bloater Coregonus hoyi: a hypothesis test

USGS Publications Warehouse

Eck, Gary W.; Allen, Jeffrey D.

1995-01-01

The hypothesis that temperature was an epigamic factor in bloater (Coregonus hoyi) sex determination in Lake Michigan was tested by rearing bloater larvae in the laboratory at 6, 11, and 15 degrees C for the first 80 days after hatching. The percentages of females of fish exposed to the three treatment temperatures did not differ significantly from the expected, 50%. Therefore, the null hypothesis, that temperature did not influence bloater sex determination within the confines of this study, could not be rejected. Our study of bloater sex determination was an attempt to explain the extreme female predominance (> 95%) that occurred in the Lake Michigan bloater population during the 1960s.

Turnover of Sex Chromosomes in the Stickleback Fishes (Gasterosteidae)

PubMed Central

Ross, Joseph A.; Urton, James R.; Boland, Jessica; Shapiro, Michael D.; Peichel, Catherine L.

2009-01-01

Diverse sex-chromosome systems are found in vertebrates, particularly in teleost fishes, where different systems can be found in closely related species. Several mechanisms have been proposed for the rapid turnover of sex chromosomes, including the transposition of an existing sex-determination gene, the appearance of a new sex-determination gene on an autosome, and fusions between sex chromosomes and autosomes. To better understand these evolutionary transitions, a detailed comparison of sex chromosomes between closely related species is essential. Here, we used genetic mapping and molecular cytogenetics to characterize the sex-chromosome systems of multiple stickleback species (Gasterosteidae). Previously, we demonstrated that male threespine stickleback fish (Gasterosteus aculeatus) have a heteromorphic XY pair corresponding to linkage group (LG) 19. In this study, we found that the ninespine stickleback (Pungitius pungitius) has a heteromorphic XY pair corresponding to LG12. In black-spotted stickleback (G. wheatlandi) males, one copy of LG12 has fused to the LG19-derived Y chromosome, giving rise to an X1X2Y sex-determination system. In contrast, neither LG12 nor LG19 is linked to sex in two other species: the brook stickleback (Culaea inconstans) and the fourspine stickleback (Apeltes quadracus). However, we confirmed the existence of a previously reported heteromorphic ZW sex-chromosome pair in the fourspine stickleback. The sex-chromosome diversity that we have uncovered in sticklebacks provides a rich comparative resource for understanding the mechanisms that underlie the rapid turnover of sex-chromosome systems. PMID:19229325

The price of sex: condom use and the determinants of the price of sex among female sex workers in eastern Zimbabwe.

PubMed

Elmes, Jocelyn; Nhongo, Kundai; Ward, Helen; Hallett, Timothy; Nyamukapa, Constance; White, Peter J; Gregson, Simon

2014-12-01

Higher prices for unprotected sex threaten the high levels of condom use that contributed to the decline in Zimbabwe's human immunodeficiency virus (HIV) epidemic. To improve understanding of financial pressures competing against safer sex, we explore factors associated with the price of commercial sex in rural eastern Zimbabwe. We collected and analyzed cross-sectional data on 311 women, recruited during October-December 2010, who reported that they received payment for their most-recent or second-most-recent sex acts in the past year. Zero-inflated negative binomial models with robust standard errors clustered on female sex worker (FSW) were used to explore social and behavioral determinants of price. The median price of sex was $10 (interquartile range [IQR], $5-$20) per night and $10 (IQR, $5-$15) per act. Amounts paid in cash and commodities did not differ significantly. At the most-recent sex act, more-educated FSWs received 30%-74% higher payments. Client requests for condom use significantly predicted protected sex (P < .01), but clients paid on average 42.9% more for unprotected sex. Within a work environment where clients' preferences determine condom use, FSWs effectively use their individual capital to negotiate the terms of condom use. Strengthening FSWs' preferences for protected sex could help maintain high levels of condom use. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America.

Applying a behavioral economic framework to understanding adolescent smoking.

PubMed

Audrain-McGovern, Janet; Rodriguez, Daniel; Tercyak, Kenneth P; Epstein, Leonard H; Goldman, Paula; Wileyto, E Paul

2004-03-01

Adolescents' choice to smoke may depend on substitute reinforcers for smoking, complementary activities to smoking, and individual differences in reinforcer value. The influence of these variables on smoking was determined among 983 adolescents. Substitutes were school involvement, academic performance, physical activity, and sports team participation: complements were peer smoking and substance use; delay discounting assessed individual differences in reinforcer value. Latent growth modeling indicated that substitute reinforcers reduced the odds of smoking progression almost two-fold, complementary reinforcers increased the odds by 1.14. and delay discounting indirectly influenced the odds of smoking progression through complementary reinforcers. Adolescents who smoke may have fewer reinforcers that protect against smoking and more reinforcers that promote smoking. Discounting of future rewards affects smoking through reinforcer type.

The timing of introduction of complementary foods and later health.

PubMed

Agostoni, Carlo; Przyrembel, Hildegard

2013-01-01

Complementary food is needed when human milk (or infant formula) alone is no longer sufficient for nutritional reasons. The timing of introduction needs to be determined on an individual basis although 6 months of exclusive breastfeeding can be recommended for most healthy term infants. Solid foods are intended to 'complement' ongoing breastfeeding with those dietary items whose intake has become marginal or insufficient. Both breastfeeding and complementary feeding can have direct or later consequences on health. Possible short-term health effects concern growth velocity and infections while possible long-term effects may relate to obesity, cardiovascular disease, autoimmunity (celiac disease and type 1 diabetes) and atopic disorders. For most of these it is impossible on the basis of the available evidence to conclude on the age when risks related to the start of complementary feeding are lowest or highest, with the possible exception of infections and early growth velocity. For undesirable health consequences, whilst potential mechanisms are recognized, the evidence from mostly observational studies is insufficient and requires more and prospective research. While the 6-month goal is desirable, introduction of suitable complementary food after 4 completed months with ongoing breastfeeding can be considered without adverse health consequences for infants living in affluent countries. Even less evidence on the consequences of the timing of complementary food introduction is available for formula-fed infants. Copyright © 2013 S. Karger AG, Basel.

Knowledge, Attitude and Practice of General Practitioners toward Complementary and Alternative Medicine: a Cross-Sectional Study.

PubMed

Barikani, Ameneh; Beheshti, Akram; Javadi, Maryam; Yasi, Marzieh

2015-08-01

Orientation of public and physicians to the complementary and alternative medicine (CAM) is one of the most prominent symbols of structural changes in the health service system. The aim of his study was a determination of knowledge, attitude, and practice of general practitioners in complementary and alternative medicine. This cross- sectional study was conducted in Qazvin, Iran in 2013. A self-administered questionnaire was used for collecting data including four information parts: population information, physicians' attitude and knowledge, methods of getting information and their function. A total of 228 physicians in Qazvin comprised the population of study according to the deputy of treatment's report of Qazvin University of Medical Sciences. A total of 150 physicians were selected randomly, and SPSS Statistical program was used to enter questionnaires' data. Results were analyzed as descriptive statistics and statistical analysis. Sixty percent of all responders were male. About sixty (59.4) percent of participating practitioners had worked less than 10 years.96.4 percent had a positive attitude towards complementary and alternative medicine. Knowledge of practitioners about traditional medicine in 11 percent was good, 36.3% and 52.7% had average and little information, respectively. 17.9% of practitioners offered their patients complementary and alternative medicine for treatment. Although there was little knowledge among practitioners about traditional medicine and complementary approaches, a significant percentage of them had attitude higher than the lower limit.

On the maintenance of sex chromosome polymorphism by sex-antagonistic selection.

PubMed

Blaser, Olivier; Neuenschwander, Samuel; Perrin, Nicolas

2011-10-01

Complex sex determination systems are a priori unstable and require specific selective forces for their maintenance. Analytical derivations suggest that sex antagonistic selection may play such a role, but this assumes absence of recombination between the sex-determining and sex-antagonistic genes. Using individual-based simulations and focusing on the sex chromosome and coloration polymorphisms of platy fishes as a case study, we show that the conditions for polymorphism maintenance induce female biases in primary sex ratios, so that sex ratio selection makes the system collapse toward male or female heterogamety as soon as recombinant genotypes appear. However, a polymorphism can still be maintained under scenarios comprising strong sexual selection against dull males, mild natural selection against bright females, and low recombination rates. Though such conditions are plausibly met in natural populations of fishes harboring such polymorphisms, quantitative empirical evaluations are required to properly test whether sex antagonistic selection is a causal agent or whether other selective processes are required (such as local mate competition favoring female-biased sex ratios).

Sex chromosome evolution: historical insights and future perspectives

PubMed Central

Nordén, Anna K.

2017-01-01

Many separate-sexed organisms have sex chromosomes controlling sex determination. Sex chromosomes often have reduced recombination, specialized (frequently sex-specific) gene content, dosage compensation and heteromorphic size. Research on sex determination and sex chromosome evolution has increased over the past decade and is today a very active field. However, some areas within the field have not received as much attention as others. We therefore believe that a historic overview of key findings and empirical discoveries will put current thinking into context and help us better understand where to go next. Here, we present a timeline of important conceptual and analytical models, as well as empirical studies that have advanced the field and changed our understanding of the evolution of sex chromosomes. Finally, we highlight gaps in our knowledge so far and propose some specific areas within the field that we recommend a greater focus on in the future, including the role of ecology in sex chromosome evolution and new multilocus models of sex chromosome divergence. PMID:28469017

Cytogenetic monitoring in a population occupationally exposed to pesticides in Ecuador.

PubMed Central

Paz-y-Miño, César; Bustamante, Gabriela; Sánchez, María Eugenia; Leone, Paola E

2002-01-01

We analyzed the incidence of structural and numerical chromosomal aberrations (CAs) in workers of a plantation of flowers located in Quito, Ecuador, in South America. This study included 41 individuals occupationally exposed to 27 pesticides, some of which are restricted in many countries and are classified as extremely toxic by the World Health Organization; among these are aldicarb and fenamiphos. The same number of individuals of the same age, sex, and geographic area were selected as controls. Workers exposed to these pesticides showed an increased frequency of CA compared with control group (20.59% vs. 2.73%; p < 0.001). We conclude that screening for CA is an adequate biomarker for evaluating and detecting genotoxicity resulting from exposure to pesticides. Levels of erythrocyte acetylcholinesterase were also determined as a complementary metabolic study. Levels below the optimal (> 28 U/mL blood) were found in 88% of exposed individuals; this clearly shows the effect of organophosphate pesticides. When comparing the levels of acetylcholinesterase and structural CA frequencies, there was a negative linear correlation (r = 0.416; p < 0.01). We conclude that by using both analyses it may be possible to estimate damage produced by exposure to organophosphate pesticides. PMID:12417477

Outbreeding and lack of temporal genetic structure in a drone congregation of the neotropical stingless bee Scaptotrigona mexicana

PubMed Central

Mueller, Matthias Y; Moritz, Robin FA; Kraus, F Bernhard

2012-01-01

Drone aggregations are a widespread phenomenon in many stingless bee species (Meliponini), but the ultimate and proximate causes for their formation are still not well understood. One adaptive explanation for this phenomenon is the avoidance of inbreeding, which is especially detrimental for stingless bees due to the combined effects of the complementary sex-determining system and the small effective population size caused by eusociality and monandry. We analyzed the temporal genetic dynamics of a drone aggregation of the stingless bee Scaptotrigona mexicana with microsatellite markers over a time window of four weeks. We estimated the drones of the aggregation to originate from a total of 55 colonies using sibship re-construction. There was no detectable temporal genetic differentiation or sub-structuring in the aggregation. Most important, we could exclude all colonies in close proximity of the aggregation as origin of the drones in the aggregation, implicating that they originate from more distant colonies. We conclude that the diverse genetic composition and the distant origin of the drones of the S. mexicana drone congregation provides an effective mechanism to avoid mating among close relatives. PMID:22833802

Outbreeding and lack of temporal genetic structure in a drone congregation of the neotropical stingless bee Scaptotrigona mexicana.

PubMed

Mueller, Matthias Y; Moritz, Robin Fa; Kraus, F Bernhard

2012-06-01

Drone aggregations are a widespread phenomenon in many stingless bee species (Meliponini), but the ultimate and proximate causes for their formation are still not well understood. One adaptive explanation for this phenomenon is the avoidance of inbreeding, which is especially detrimental for stingless bees due to the combined effects of the complementary sex-determining system and the small effective population size caused by eusociality and monandry. We analyzed the temporal genetic dynamics of a drone aggregation of the stingless bee Scaptotrigona mexicana with microsatellite markers over a time window of four weeks. We estimated the drones of the aggregation to originate from a total of 55 colonies using sibship re-construction. There was no detectable temporal genetic differentiation or sub-structuring in the aggregation. Most important, we could exclude all colonies in close proximity of the aggregation as origin of the drones in the aggregation, implicating that they originate from more distant colonies. We conclude that the diverse genetic composition and the distant origin of the drones of the S. mexicana drone congregation provides an effective mechanism to avoid mating among close relatives.

Sex determination and differentiation in Aurelia sp.1: the absence of temperature dependence

NASA Astrophysics Data System (ADS)

Liu, Chunsheng; Gu, Zhifeng; Xing, Mengxin; Sun, Yun; Chen, Siqing; Chen, Zhaoting

2018-03-01

Cnidarians, being regarded as `basal' metazoan animals, are considered to have relatively high plasticity in terms of sex reversal. In this study we used an experimental approach to demonstrate sexual differentiation and plasticity in benthic polyps and pelagic medusae of Aurelia sp.1 maintained at different temperatures. Results indicated that in Aurelia sp.1, sex differentiation has been determined at the polyp stage and that all medusae originating from a given polyp are, phenotypically, of the same sex. In addition, the sex of polyps budding from the same clone (either male or female) at different temperatures appears to be the same as that of the parent. The sex of medusae that had originated from a known-sex polyp was observed to remain the same as that of the parent, irrespective of differences in strobilation or rearing temperatures. These results indicate that the mechanism of sex determination of Aurelia sp.1. is not influenced by prevailing temperature regimes. A comparison of variability in terms of sexual plasticity of Aurelia sp.1 with that of Hydrozoa and Anthozoa suggests that species characterized by a free-swimming medusa life stage have a high dispersal potential, which probably results in a lower rate of sex reversal.

Male only progeny in Anastrepha suspensa by RNAi-induced sex reversion of chromosomal females

USDA-ARS?s Scientific Manuscript database

In Tephritidae sex determination is established by orthologs to the Drosophila melanogaster transformer and transformer-2 genes. In contrast, primary signals for sex determination are different in these species corresponding to the number of X chromosomes (XSE) in Drosophilidae species and to the pr...

Determinants of Safer Sex Behaviors among College Students

ERIC Educational Resources Information Center

Kanekar, Amar; Sharma, Manoj

2010-01-01

Safer sex behaviors (monogamy, sexual abstinence, correct and consistent condom usage) are important for prevention of sexually transmitted diseases and HIV/AIDS among college students. The purpose of this article was to review studies addressing determinants of safer sex behaviors among college students. In order to collect materials for this…

Physical Attractiveness, Age, and Sex as Determinants of Reactions to Resumes.

ERIC Educational Resources Information Center

Quereshi, M. Y.; Kay, Janet P.

1986-01-01

Physical attractiveness, age, and sex were manipulated to determine their effect on the evaluation of 54 hypothetical applicants' resumes for three different jobs by 60 Master's in Business Administration students. Physical attractiveness favorably influenced the suitability ratings for all jobs; raters' sex and age were not significant but…

Sex, genes, and heat: triggers of diversity.

PubMed

Western, P S; Sinclair, A H

2001-11-01

In vertebrates, sex is determined by a surprising variety of mechanisms. In many reptiles, the primary testis or ovary-determining trigger is regulated by egg incubation temperature. This temperature dependent sex determining (TSD) mechanism occurs in all crocodilians and marine turtles examined to date and is common in terrestrial turtles and viviparous lizards (Ewert et al. 1994. J Exp Zool 270:3-15; Lang and Andrews. 1994. J Exp Biol 270:28-44; Mrosovsky. 1994. J Exp Zool 270:16-27; Pieau. 1996. Bioessays 18:19-26; Viets et al. 1994. J Exp Zool 270:45-56; Wibbels et al. 1998. J Exp Zool 281:409-416). In contrast, sex in mammals and birds is determined chromosomally (CSD). Despite these differences, morphological development of the gonads in all these vertebrate groups appears to have been conserved through evolution. Therefore, the genetic mechanisms triggering sex determination appear not to have been conserved through evolution, although the basic genetic pathway controlling the morphological differentiation of the gonads appears to have been conserved. Copyright 2001 Wiley-Liss, Inc.

Observation of a ZZW female in a natural population: implications for avian sex determination.

PubMed Central

Arit, D; Bensch, S; Hansson, B; Hasselquist, D; Westerdahl, H

2004-01-01

Avian sex determination is chromosomal; however, the underlying mechanisms are not yet understood. There is no conclusive evidence for either of two proposed mechanisms: a dominant genetic switch or a dosage mechanism. No dominant sex-determining gene on the female-specific W chromosome has been found. Birds lack inactivation of one of the Z chromosomes in males, but seem to compensate for a double dose of Z-linked genes by other mechanisms. Recent studies showing female-specific expression of two genes may support an active role of the W chromosome. To resolve the question of avian sex determination the investigation of birds with a 2A: ZZW or 2A: ZO genotype would be decisive. Here, we report the case of an apparent 2A: ZZW great reed warbler (Acrocephalus arundinaceus) female breeding in a natural population, which was detected using Z-linked microsatellites. Our data strongly suggest a role of W-linked genes in avian sex determination. PMID:15252998

Three loci on mouse chromosome 5 and 10 modulate sex determination in XX Ods/+ mice.

PubMed

Poirier, Christophe; Moran, Jennifer L; Kovanci, Ertug; Petit, Deborah C; Beier, David R; Bishop, Colin E

2007-07-01

In mouse, XY embryos are committed to the male sex determination pathway after the transient expression of the Y-linked Sry gene in the Sertoli cell lineage between 10.5 and 12.5 dpc. In the C57BL/6J strain, male sex determination program can be modulated by some autosomal genes. The C57BL/6J alleles at these autosomal loci can antagonize male sex determination in combination with specific Sry alleles. In this report, the authors have identified an effect of these C57BL/6J specific alleles in combination with a mutated Sox9 allele, Sox9(Ods). Authors report the mapping of three of these genetic loci on mouse chromosome 5 and 10 in a backcross of the Ods mutation to the C57BL/6J background. Our study confirms the importance of the strain C57BL/6J for the investigation of the genetic mechanisms that control sex determination.

The Riddle of Sex.

ERIC Educational Resources Information Center

Sagan, Dorion; Margulis, Lynn

1985-01-01

Discusses the work of evolutionary biologists in determining how sexual reproduction arose. Topics explored include the nature of sex, bacterial sex, meiotic sex, and asexual reproduction. A diagram (which can be used as a duplicating master) illustrating types of bacterial sex is included. (DH)

A noninvasive, direct real-time PCR method for sex determination in multiple avian species

USGS Publications Warehouse

Brubaker, Jessica L.; Karouna-Renier, Natalie K.; Chen, Yu; Jenko, Kathryn; Sprague, Daniel T.; Henry, Paula F.P.

2011-01-01

Polymerase chain reaction (PCR)-based methods to determine the sex of birds are well established and have seen few modifications since they were first introduced in the 1990s. Although these methods allowed for sex determination in species that were previously difficult to analyse, they were not conducive to high-throughput analysis because of the laboriousness of DNA extraction and gel electrophoresis. We developed a high-throughput real-time PCR-based method for analysis of sex in birds, which uses noninvasive sample collection and avoids DNA extraction and gel electrophoresis.

Steroid Signaling and Temperature-Dependent Sex Determination – Reviewing the Evidence for Early Action of Estrogen during Ovarian Determination in the Red-Eared Slider Turtle (Trachemys scripta elegans)

PubMed Central

Ramsey, Mary; Crews, David

2009-01-01

The developmental processes underlying gonadal differentiation are conserved across vertebrates, but the triggers initiating these trajectories are extremely variable. The red-eared slider turtle (Trachemys scripta elegans) exhibits temperature-dependent sex determination (TSD), a system where incubation temperature during a temperature-sensitive period of development determines offspring sex. However, gonadal sex is sensitive to both temperature and hormones during this period – particularly estrogen. We present a model for temperature-based differences in aromatase expression as a critical step in ovarian determination. Localized estrogen production facilitates ovarian development while inhibiting male-specific gene expression. At male-producing temperatures aromatase is not upregulated, thereby allowing testis development. PMID:18992835

Sex determination in goat by amplification of the HMG box using duplex PCR.

PubMed

Shi, Lei; Yue, Wenbin; Ren, Youshe; Lei, Fulin; Zhao, Junxing

2008-05-01

The objective of this study was to obtain a fast, accurate and reliable method of determining the sex of goat embryos prior to implantation through amplification of the high-motility-group (HMG) box of the sex-determining region of the Y chromosome (SRY) gene of the goats. Goat specific primers were designed for duplex polymerase chain reaction (PCR). As an internal control gene, the goat beta-action gene sequence was simultaneously amplified together with the HMG box of goat SRY gene. Males showed both 1 SRY band and 1 beta-action band, but only 1 beta-action band was present in the agarose gel electrophoresis of females. The result indicated that the goat HMG-box sequence motif of SRY was male specific. Afterward, the optimized PCR procedure was applied in 30 embryo biopsies and the biopsied embryos were transferred into 30 recipient female goats. The sex of the 13 kids proved anatomically corresponded to the sex determined by PCR (100% accuracy). Thus, this study showed that this duplex PCR method can be applied to sex the goat pre-implantation embryos and to manipulate the sex ratio of offspring in goat breeding programs.

Biochemical and Functional Analysis of Drosophila-Sciara Chimeric Sex-Lethal Proteins

PubMed Central

Ruiz, María Fernanda; Sarno, Francesca; Zorrilla, Silvia; Rivas, Germán; Sánchez, Lucas

2013-01-01

Background The Drosophila SXL protein controls sex determination and dosage compensation. It is a sex-specific factor controlling splicing of its own Sxl pre-mRNA (auto-regulation), tra pre-mRNA (sex determination) and msl-2 pre-mRNA plus translation of msl-2 mRNA (dosage compensation). Outside the drosophilids, the same SXL protein has been found in both sexes so that, in the non-drosophilids, SXL does not appear to play the key discriminating role in sex determination and dosage compensation that it plays in Drosophila. Comparison of SXL proteins revealed that its spatial organisation is conserved, with the RNA-binding domains being highly conserved, whereas the N- and C-terminal domains showing significant variation. This manuscript focuses on the evolution of the SXL protein itself and not on regulation of its expression. Methodology Drosophila-Sciara chimeric SXL proteins were produced. Sciara SXL represents the non-sex-specific function of ancient SXL in the non-drosophilids from which presumably Drosophila SXL evolved. Two questions were addressed. Did the Drosophila SXL protein have affected their functions when their N- and C-terminal domains were replaced by the corresponding ones of Sciara? Did the Sciara SXL protein acquire Drosophila sex-specific functions when the Drosophila N- and C-terminal domains replaced those of Sciara? The chimeric SXL proteins were analysed in vitro to study their binding affinity and cooperative properties, and in vivo to analyse their effect on sex determination and dosage compensation by producing Drosophila flies that were transgenic for the chimeric SXL proteins. Conclusions The sex-specific properties of extant Drosophila SXL protein depend on its global structure rather than on a specific domain. This implies that the modifications, mainly in the N- and C-terminal domains, that occurred in the SXL protein during its evolution within the drosophilid lineage represent co-evolutionary changes that determine the appropriate folding of SXL to carry out its sex-specific functions. PMID:23762307

Use of complementary and alternative medicine for work related musculoskeletal disorders associated with job contentment in dental professionals: Indian outlook.

PubMed

Gupta, Devanand; Bhaskar, Dara John; Gupta, Kumar Rajendra; Karim, Bushra; Kanwar, Alpana; Jain, Ankita; Yadav, Ankit; Saini, Priya; Arya, Satya; Sachdeva, Neha

2014-04-01

High prevalence rates of work-related musculoskeletal disorders (WRMSD) among dentists have been reported. Complementary and alternative medicine (CAM) therapies can be helpful in managing and preventing work-related musculoskeletal disorders. The purpose of this study was to determine if dental professionals are using CAM for work-related musculoskeletal disorders. Who have greater job satisfaction: dentist who uses Complementary and alternative medicine (CAM) or conventional therapy (CT) as a treatment modality for WRMSD. Dentists who registered in Uttar Pradesh state, India under Indian Dental Council, Uttar Pradesh branch (n=1134) were surveyed. Data were analyzed using univariate and bivariate analyses and logistic regression. A response rate of 53% (n=601) was obtained, revealing that 82% (n=487) of the respondents suffered from work-related musculoskeletal disorders. The use of complementary and alternative medicine or conventional therapy was reported among 80% (n=390) of the dentists with work-related musculoskeletal disorders. Complementary and alternative medicine users reported greater overall health compared to conventional therapy users (P<0.001). Of those with work-related musculoskeletal disorders, 35.5% (n=172) considered a career change for once, and 4.0% (n=19) reported having left dentistry. Complementary and alternative medicine therapies may improve quality of life, reduce work disruptions and enhance job satisfaction for dentists who suffer from work-related musculoskeletal disorders. It is important that dentists incorporate complementary and alternative medicine strategies into practice to facilitate musculoskeletal health that will enable longer and healthier careers, increase productivity, provide safer workplace and prevent musculoskeletal disorders.

Use of Complementary and Alternative Medicine for Work Related Musculoskeletal Disorders Associated With Job Contentment in Dental Professionals: Indian Outlook

PubMed Central

Gupta, Devanand; Bhaskar, Dara John; Gupta, Kumar Rajendra; Karim, Bushra; Kanwar, Alpana; Jain, Ankita; Yadav, Ankit; Saini, Priya; Arya, Satya; Sachdeva, Neha

2014-01-01

Background High prevalence rates of work-related musculoskeletal disorders (WRMSD) among dentists have been reported. Complementary and alternative medicine (CAM) therapies can be helpful in managing and preventing work-related musculoskeletal disorders. The purpose of this study was to determine if dental professionals are using CAM for work-related musculoskeletal disorders. Who have greater job satisfaction: dentist who uses Complementary and alternative medicine (CAM) or conventional therapy (CT) as a treatment modality for WRMSD Method Dentists who registered in Uttar Pradesh state, India under Indian Dental Council, Uttar Pradesh branch (n=1134) were surveyed. Data were analyzed using univariate and bivariate analyses and logistic regression. Result A response rate of 53% (n=601) was obtained, revealing that 82% (n=487) of the respondents suffered from work-related musculoskeletal disorders. The use of complementary and alternative medicine or conventional therapy was reported among 80% (n=390) of the dentists with work-related musculoskeletal disorders. Complementary and alternative medicine users reported greater overall health compared to conventional therapy users (P<0.001). Of those with work-related musculoskeletal disorders, 35.5% (n=172) considered a career change for once, and 4.0% (n=19) reported having left dentistry. Conclusion Complementary and alternative medicine therapies may improve quality of life, reduce work disruptions and enhance job satisfaction for dentists who suffer from work-related musculoskeletal disorders. It is important that dentists incorporate complementary and alternative medicine strategies into practice to facilitate musculoskeletal health that will enable longer and healthier careers, increase productivity, provide safer workplace and prevent musculoskeletal disorders. PMID:24795512

Sources, distribution, bioavailability, toxicity, and risk assessment of heavy metal(loid)s in complementary medicines.

PubMed

Bolan, Shiv; Kunhikrishnan, Anitha; Seshadri, Balaji; Choppala, Girish; Naidu, Ravi; Bolan, Nanthi S; Ok, Yong Sik; Zhang, Ming; Li, Chun-Guang; Li, Feng; Noller, Barry; Kirkham, Mary Beth

2017-11-01

The last few decades have seen the rise of alternative medical approaches including the use of herbal supplements, natural products, and traditional medicines, which are collectively known as 'Complementary medicines'. However, there are increasing concerns on the safety and health benefits of these medicines. One of the main hazards with the use of complementary medicines is the presence of heavy metal(loid)s such as arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg). This review deals with the characteristics of complementary medicines in terms of heavy metal(loid)s sources, distribution, bioavailability, toxicity, and human risk assessment. The heavy metal(loid)s in these medicines are derived from uptake by medicinal plants, cross-contamination during processing, and therapeutic input of metal(loid)s. This paper discusses the distribution of heavy metal(loid)s in these medicines, in terms of their nature, concentration, and speciation. The importance of determining bioavailability towards human health risk assessment was emphasized by the need to estimate daily intake of heavy metal(loid)s in complementary medicines. The review ends with selected case studies of heavy metal(loid) toxicity from complementary medicines with specific reference to As, Cd, Pb, and Hg. The future research opportunities mentioned in the conclusion of review will help researchers to explore new avenues, methodologies, and approaches to the issue of heavy metal(loid)s in complementary medicines, thereby generating new regulations and proposing fresh approach towards safe use of these medicines. Copyright © 2017 Elsevier Ltd. All rights reserved.

The birds and the bees and the flowers and the trees: lessons from genetic mapping of sex determination in plants and animals.

PubMed

Charlesworth, Deborah; Mank, Judith E

2010-09-01

The ability to identify genetic markers in nonmodel systems has allowed geneticists to construct linkage maps for a diversity of species, and the sex-determining locus is often among the first to be mapped. Sex determination is an important area of study in developmental and evolutionary biology, as well as ecology. Its importance for organisms might suggest that sex determination is highly conserved. However, genetic studies have shown that sex determination mechanisms, and the genes involved, are surprisingly labile. We review studies using genetic mapping and phylogenetic inferences, which can help reveal evolutionary pattern within this lability and potentially identify the changes that have occurred among different sex determination systems. We define some of the terminology, particularly where confusion arises in writing about such a diverse range of organisms, and highlight some major differences between plants and animals, and some important similarities. We stress the importance of studying taxa suitable for testing hypotheses, and the need for phylogenetic studies directed to taxa where the patterns of changes can be most reliably inferred, if the ultimate goal of testing hypotheses regarding the selective forces that have led to changes in such an essential trait is to become feasible.

Environmental sex determination mechanisms in reptiles.

PubMed

Merchant-Larios, H; Díaz-Hernández, V

2013-01-01

Temperature-dependent sex determination (TSD) was first discovered in reptiles. Since then, a great diversity of sex-determining responses to temperature has been reported. Higher temperatures can produce either males or females, and the temperature ranges and lengths of exposure that influence TSD are remarkably variable among species. In addition, transitory gene regulatory networks leading to gonadal TSD have evolved. Although most genes involved in gonadal development are conserved in vertebrates, including TSD species, temporal and spatial gene expression patterns vary among species. Despite variation in TSD pattern and gene expression heterochrony, the structural framework, the medullary cords, and cortex of the bipotential gonad have been strongly conserved. Aromatase (CYP19), which regulates gonadal estrogen levels, is proposed to be the main target of a putative thermosensitive factor for TSD. However, manipulation of estrogen levels rarely mimics the precise timing of temperature effects on expression of gonadal genes, as occurs with TSD. Estrogen levels may influence sex determination or gonad differentiation depending on the species. Furthermore, the process leading to sex determination under the influence of temperature poses problems that are not encountered by species with genetic sex determination. Yolk steroids of maternal origin and steroids produced by the embryonic nervous system should also be considered as sources of hormones that may play a role in TSD. Copyright © 2012 S. Karger AG, Basel.

Genetic and epigenetic effects in sex determination.

PubMed

Gunes, Sezgin Ozgur; Metin Mahmutoglu, Asli; Agarwal, Ashok

2016-12-01

Sex determination is a complex and dynamic process with multiple genetic and environmental causes, in which germ and somatic cells receive various sex-specific features. During the fifth week of fetal life, the bipotential embryonic gonad starts to develop in humans. In the bipotential gonadal tissue, certain cell groups start to differentiate to form the ovaries or testes. Despite considerable efforts and advances in identifying the mechanisms playing a role in sex determination and differentiation, the underlying mechanisms of the exact functions of many genes, gene-gene interactions, and epigenetic modifications that are involved in different stages of this cascade are not completely understood. This review aims at discussing current data on the genetic effects via genes and epigenetic mechanisms that affect the regulation of sex determination. Birth Defects Research (Part C) 108:321-336, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Sequential Turnovers of Sex Chromosomes in African Clawed Frogs (Xenopus) Suggest Some Genomic Regions Are Good at Sex Determination

PubMed Central

Furman, Benjamin L. S.; Evans, Ben J.

2016-01-01

Sexual differentiation is fundamentally important for reproduction, yet the genetic triggers of this developmental process can vary, even between closely related species. Recent studies have uncovered, for example, variation in the genetic triggers for sexual differentiation within and between species of African clawed frogs (genus Xenopus). Here, we extend these discoveries by demonstrating that yet another sex determination system exists in Xenopus, specifically in the species Xenopus borealis. This system evolved recently in an ancestor of X. borealis that had the same sex determination system as X. laevis, a system which itself is newly evolved. Strikingly, the genomic region carrying the sex determination factor in X. borealis is homologous to that of therian mammals, including humans. Our results offer insights into how the genetic underpinnings of conserved phenotypes evolve, and suggest an important role for cooption of genetic building blocks with conserved developmental roles. PMID:27605520

Implications of monotreme and marsupial chromosome evolution on sex determination and differentiation.

PubMed

Deakin, Janine E

2017-04-01

Studies of chromosomes from monotremes and marsupials endemic to Australasia have provided important insight into the evolution of their genomes as well as uncovering fundamental differences in their sex determination/differentiation pathways. Great advances have been made this century into solving the mystery of the complicated sex chromosome system in monotremes. Monotremes possess multiple different X and Y chromosomes and a candidate sex determining gene has been identified. Even greater advancements have been made for marsupials, with reconstruction of the ancestral karyotype enabling the evolutionary history of marsupial chromosomes to be determined. Furthermore, the study of sex chromosomes in intersex marsupials has afforded insight into differences in the sexual differentiation pathway between marsupials and eutherians, together with experiments showing the insensitivity of the mammary glands, pouch and scrotum to exogenous hormones, led to the hypothesis that there is a gene (or genes) on the X chromosome responsible for the development of either pouch or scrotum. This review highlights the major advancements made towards understanding chromosome evolution and how this has impacted on our understanding of sex determination and differentiation in these interesting mammals. Copyright © 2015 Elsevier Inc. All rights reserved.

Non-invasive fetal sex determination by maternal plasma sequencing and application in X-linked disorder counseling.

PubMed

Pan, Xiaoyu; Zhang, Chunlei; Li, Xuchao; Chen, Shengpei; Ge, Huijuan; Zhang, Yanyan; Chen, Fang; Jiang, Hui; Jiang, Fuman; Zhang, Hongyun; Wang, Wei; Zhang, Xiuqing

2014-12-01

To develop a fetal sex determination method based on maternal plasma sequencing (MPS), assess its performance and potential use in X-linked disorder counseling. 900 cases of MPS data from a previous study were reviewed, in which 100 and 800 cases were used as training and validation set, respectively. The percentage of uniquely mapped sequencing reads on Y chromosome was calculated and used to classify male and female cases. Eight pregnant women who are carriers of Duchenne muscular dystrophy (DMD) mutations were recruited, whose plasma were subjected to multiplex sequencing and fetal sex determination analysis. In the training set, a sensitivity of 96% and false positive rate of 0% for male cases detection were reached in our method. The blinded validation results showed 421 in 423 male cases and 374 in 377 female cases were successfully identified, revealing sensitivity and specificity of 99.53% and 99.20% for fetal sex determination, at as early as 12 gestational weeks. Fetal sex for all eight DMD genetic counseling cases were correctly identified, which were confirmed by amniocentesis. Based on MPS, high accuracy of non-invasive fetal sex determination can be achieved. This method can potentially be used for prenatal genetic counseling.

Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

PubMed

Pandey, Ravi S; Azad, Rajeev K

2016-03-01

Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non-recombining region of both the chromosomes.

Co-option of the bZIP transcription factor Vrille as the activator of Doublesex1 in environmental sex determination of the crustacean Daphnia magna.

PubMed

Mohamad Ishak, Nur Syafiqah; Nong, Quang Dang; Matsuura, Tomoaki; Kato, Yasuhiko; Watanabe, Hajime

2017-11-01

Divergence of upstream regulatory pathways of the transcription factor Doublesex (Dsx) serves as a basis for evolution of sex-determining mechanisms in animals. However, little is known about the regulation of Dsx in environmental sex determination. In the crustacean Daphnia magna, environmental sex determination is implemented by male-specific expression of the Dsx ortholog, Dsx1. Transcriptional regulation of Dsx1 comprises at least three phases during embryogenesis: non-sex-specific initiation, male-specific up-regulation, and its maintenance. Herein, we demonstrate that the male-specific up-regulation is controlled by the bZIP transcription factor, Vrille (Vri), an ortholog of the circadian clock genes-Drosophila Vri and mammalian E4BP4/NFIL3. Sequence analysis of the Dsx1 promoter/enhancer revealed a conserved element among two Daphnia species (D. magna and D. pulex), which contains a potential enhancer harboring a consensus Vri binding site overlapped with a consensus Dsx binding site. Besides non-sex-specific expression of Vri in late embryos, we found male-specific expression in early gastrula before the Dsx1 up-regulation phase begins. Knockdown of Vri in male embryos showed reduction of Dsx1 expression. In addition, transient overexpression of Vri in early female embryos up-regulated the expression of Dsx1 and induced male-specific trait. Targeted mutagenesis using CRISPR/Cas9 disrupted the enhancer on genome in males, which led to the reduction of Dsx1 expression. These results indicate that Vri was co-opted as a transcriptional activator of Dsx1 in environmental sex determination of D. magna. The data suggests the remarkably plastic nature of gene regulatory network in sex determination.

Co-option of the bZIP transcription factor Vrille as the activator of Doublesex1 in environmental sex determination of the crustacean Daphnia magna

PubMed Central

Nong, Quang Dang; Matsuura, Tomoaki; Watanabe, Hajime

2017-01-01

Divergence of upstream regulatory pathways of the transcription factor Doublesex (Dsx) serves as a basis for evolution of sex-determining mechanisms in animals. However, little is known about the regulation of Dsx in environmental sex determination. In the crustacean Daphnia magna, environmental sex determination is implemented by male-specific expression of the Dsx ortholog, Dsx1. Transcriptional regulation of Dsx1 comprises at least three phases during embryogenesis: non-sex-specific initiation, male-specific up-regulation, and its maintenance. Herein, we demonstrate that the male-specific up-regulation is controlled by the bZIP transcription factor, Vrille (Vri), an ortholog of the circadian clock genes—Drosophila Vri and mammalian E4BP4/NFIL3. Sequence analysis of the Dsx1 promoter/enhancer revealed a conserved element among two Daphnia species (D. magna and D. pulex), which contains a potential enhancer harboring a consensus Vri binding site overlapped with a consensus Dsx binding site. Besides non-sex-specific expression of Vri in late embryos, we found male-specific expression in early gastrula before the Dsx1 up-regulation phase begins. Knockdown of Vri in male embryos showed reduction of Dsx1 expression. In addition, transient overexpression of Vri in early female embryos up-regulated the expression of Dsx1 and induced male-specific trait. Targeted mutagenesis using CRISPR/Cas9 disrupted the enhancer on genome in males, which led to the reduction of Dsx1 expression. These results indicate that Vri was co-opted as a transcriptional activator of Dsx1 in environmental sex determination of D. magna. The data suggests the remarkably plastic nature of gene regulatory network in sex determination. PMID:29095827

Estimating the use of morphometric measurements from museum specimens for sex determination in Mountain Plovers (Charadrius montanus)

USGS Publications Warehouse

Iko, W.M.; Dinsmore, S.J.; Knopf, F.L.

2004-01-01

The Mountain Plover (Charadrius montanus) is a shorebird species endemic to the dry, terrestrial ecosystems of the Great Plains and southwestern United States. Breeding Bird Survey data suggest that Mountain Plover populations have declined by >60% in the last 30 years. A better understanding of the population dynamics of the Mountain Plover is important in determining future management goals for this species. However, this effort is hampered by the inability to determine the sex of Mountain Plovers accurately under field conditions. In an effort to develop a simple method for sexing plovers in the hand, we measured external morphometric characteristics from 190 museum specimens of adult Mountain Plovers in alternate (breeding) plumage. Logistic regression and discriminant function analyses were performed on 10 external morphometric measurements (lengths of unflattened wing chord, 10th primary, central rectrix, outer rectrix, total head length, exposed culmen, culmen, bill depth, bill width, and tarsus). The results of these analyses indicated that Mountain Plover sexes were similar for all measures except culmen length. However, further analysis determined that culmen length accurately predicted sex in less than two-thirds of the specimens, suggesting that this measure is a poor predictor of sex in Mountain Plovers. Structurally, Mountain Plovers appear to be nearly identical between the sexes, and other methods of sexing birds (e.g., plumage characteristics, behavioral observations, or molecular markers) should be further assessed for devising a simple method for sexing Mountain Plovers under field conditions.

Sex determination of a Tunisian population by CT scan analysis of the skull.

PubMed

Zaafrane, Malek; Ben Khelil, Mehdi; Naccache, Ines; Ezzedine, Ekbel; Savall, Frédéric; Telmon, Norbert; Mnif, Najla; Hamdoun, Moncef

2018-05-01

It is widely accepted that the estimation of biological attributes in the human skeleton is more accurate when population-specific standards are applied. With the shortage of such data for contemporary North African populations, it is duly required to establish population-specific standards. We present here the first craniometric standards for sex determination of a contemporary Tunisian population. The aim of this study was to analyze the correlation between sex and metric parameters of the skull in this population using CT scan analysis and to generate proper reliable standards for sex determination of a complete or fragmented skull. The study sample comprised cranial multislice computed tomography scans of 510 individuals equally distributed by sex. ASIR TM software in a General Electric TM workstation was used to position 37 landmarks along the volume-rendered images and the multiplanar slices, defining 27 inter-landmark distances. Frontal and parietal bone thickness was also measured for each case. The data were analyzed using basic descriptive statistics and logistic regression with cross-validation of classification results. All of the measurements were sexually dimorphic with male values being higher than female values. A nine-variable model achieved the maximum classification accuracy of 90% with -2.9% sex bias and a six-variable model yielded 85.9% sexing accuracy with -0.97% sex bias. We conclude that the skull is highly dimorphic and represents a reliable bone for sex determination in contemporary Tunisian individuals.

Unexpected resilience of species with temperature-dependent sex determination at the Cretaceous–Palaeogene boundary

PubMed Central

Silber, Sherman; Geisler, Jonathan H.; Bolortsetseg, Minjin

2011-01-01

It has been suggested that climate change at the Cretaceous–Palaeogene (K–Pg) boundary, initiated by a bolide impact or volcanic eruptions, caused species with temperature-dependent sex determination (TSD), including dinosaurs, to go extinct because of a skewed sex ratio towards all males. To test this hypothesis, the sex-determining mechanisms (SDMs) of Cretaceous tetrapods of the Hell Creek Formation (Montana, USA) were inferred using parsimony optimizations of SDMs on a tree, including Hell Creek species and their extant relatives. Although the SDMs of non-avian dinosaurs could not be inferred, we were able to determine the SDMs of 62 species; 46 had genotypic sex determination (GSD) and 16 had TSD. The TSD hypothesis for extinctions performed poorly, predicting between 32 and 34 per cent of survivals and extinctions. Most surprisingly, of the 16 species with TSD, 14 of them survived into the Early Palaeocene. In contrast, 61 per cent of species with GSD went extinct. Possible explanations include minimal climate change at the K–Pg, or if climate change did occur, TSD species that survived had egg-laying behaviour that prevented the skewing of sex ratios, or had a sex ratio skewed towards female rather than male preponderance. Application of molecular clocks may allow the SDMs of non-avian dinosaurs to be inferred, which would be an important test of the pattern discovered here. PMID:20980293

Sex determination from the calcaneus in a 20th century Greek population using discriminant function analysis.

PubMed

Peckmann, Tanya R; Orr, Kayla; Meek, Susan; Manolis, Sotiris K

2015-12-01

The skull and post-cranium have been used for the determination of sex for unknown human remains. However, in forensic cases where skeletal remains often exhibit postmortem damage and taphonomic changes the calcaneus may be used for the determination of sex as it is a preservationally favored bone. The goal of the present research was to derive discriminant function equations from the calcaneus for estimation of sex from a contemporary Greek population. Nine parameters were measured on 198 individuals (103 males and 95 females), ranging in age from 20 to 99 years old, from the University of Athens Human Skeletal Reference Collection. The statistical analyses showed that all variables were sexually dimorphic. Discriminant function score equations were generated for use in sex determination. The average accuracy of sex classification ranged from 70% to 90% for the univariate analysis, 82.9% to 87.5% for the direct method, and 86.2% for the stepwise method. Comparisons to other populations were made. Overall, the cross-validated accuracies ranged from 48.6% to 56.1% with males most often identified correctly and females most often misidentified. The calcaneus was shown to be useful for sex determination in the twentieth century Greek population. Copyright © 2015 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

An Unusual Role for doublesex in Sex Determination in the Dipteran Sciara.

PubMed

Ruiz, María Fernanda; Alvarez, Mercedes; Eirín-López, José M; Sarno, Francesca; Kremer, Leonor; Barbero, José L; Sánchez, Lucas

2015-08-01

The gene doublesex, which is placed at the bottom of the sex-determination gene cascade, plays the ultimate discriminatory role for sex determination in insects. In all insects where this gene has been characterized, the dsx premessenger RNA (pre-mRNA) follows a sex-specific splicing pattern, producing male- and female-specific mRNAs encoding the male-DSXM and female-DSXF proteins, which determine male and female development, respectively. This article reports the isolation and characterization of the gene doublesex of dipteran Sciara insects. The Sciara doublesex gene is constitutively transcribed during development and adult life of males and females. Sciara had no sex-specific doublesex mRNAs but the same transcripts, produced by alternative splicing of its primary transcript, were present in both sexes, although their relative abundance is sex specific. However, only the female DSXF protein, but not the male DSXM protein, was produced at similar amounts in both sexes. An analysis of the expression of female and male Sciara DSX proteins in Drosophila showed that these proteins conserved female and male function, respectively, on the control of Drosophila yolk-protein genes. The molecular evolution of gene doublesex of all insects where this gene has been characterized revealed that Sciara doublesex displays a considerable degree of divergence in its molecular organization and its splicing pattern with respect to the rest of dipterans as suggested by its basal position within the doublesex phylogeny. It is suggested that the doublesex gene is involved in Sciara sex determination although it appears not to play the discriminatory role performed in other insects. Copyright © 2015 by the Genetics Society of America.

[Macula study in Stargardt's disease].

PubMed

Maia, Otacílio de Oliveira; Takahashi, Walter Yukihiko; Arantes, Tiago Eugênio Faria e; Barreto, Raquel Barbosa Paes; Andrade Neto, João Lins de

2008-01-01

To evaluate de macular structural damage in Stargardt's disease by optical coherence tomography, correlating with visual acuity and disease duration. Patients with Stargardt's disease were included and submitted to visual acuity (logMAR) measurement and complementary examinations performed were color fundus photographs, fluorescein angiography and optical coherence tomography. All cases were reexamined for diagnostic confirmation and the duration of symptoms was determined. The control group was composed of the same number of subjects, matched by sex and age, without any ophthalmologic alteration. The sample was composed of 22 patients (44 eyes) with Stargardt's disease, 11 (50%) males and 11 (50%) females. The duration of the disease varied from 3 to 21 years (mean of 11.4 +/- 5.3 years). The groups did not show significant differences in age (p= 0.98) and sex. Concerning the macular thickness in optical coherence tomography, the variation in the study group differed significantly from the control group, presenting smaller values of thickness (p<0.001). There was negative and significant correlation between the duration of disease and the macular thickness assessed by optical coherence tomography (r=-0.57 and p=0.005). There was positive correlation between the duration of the disease and the visual acuity (r=0.50 and p=0.0167) and negative correlation between the visual acuity and the macular thickness in optical coherence tomography (r=-0.83 and p=0.0001). It was evidenced that patients with Stargardt's disease have a thinner macular thickness when compared to normal subjects, and this reduction is related to the duration of symptoms of the disease. Additionally, the thickness and also the duration of the disease influence the visual prognosis of the patients.

Dietary Patterns Derived Using Exploratory and Confirmatory Factor Analysis are Stable and Generalizable Across Race, Region, and Gender Subgroups in the REGARDS Study

PubMed Central

Judd, Suzanne E.; Letter, Abraham J.; Shikany, James M.; Roth, David L.; Newby, P. K.

2015-01-01

Background: Examining diet as a whole using dietary patterns as exposures is a complementary method to using single food or nutrients in studies of diet and disease, but the generalizability of intake patterns across race, region, and gender in the United States has not been established. Objective: To employ rigorous statistical analysis to empirically derive dietary patterns in a large bi-racial, geographically diverse population and examine whether results are stable across population subgroups. Design: The present analysis utilized data from 21,636 participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study who completed the Block 98 food frequency questionnaire. We employed exploratory factor analysis and confirmatory factor analyses on 56 different food groups iteratively and examined differences by race, region, and sex to determine the optimal factor solution in our sample. Results: Five dietary patterns emerged: the “Convenience” pattern was characterized by mixed dishes; the “Plant-based” pattern by fruits, vegetables, and fish; the “Sweets/Fats” pattern by sweet snacks, desserts, and fats and oils; the “Southern” pattern by fried foods, organ meat, and sweetened beverages; and the “Alcohol/Salads” pattern by beer, wine, liquor, and salads. Differences were most pronounced in the Southern pattern with black participants, those residing in the Southeast, and participants not completing high school having the highest scores. Conclusion: Five meaningful dietary patterns emerged in the REGARDS study and showed strong congruence across race, sex, and region. Future research will examine associations between these patterns and health outcomes to better understand racial disparities in disease and inform prevention efforts. PMID:25988129

Sexed-semen usage for Holstein AI in the United States

USDA-ARS?s Scientific Manuscript database

The dairy industry has used sexed-semen to reduce the birth of undesirable bull calves for over a decade. While the efficacy of sexed-semen has been determined experimentally, we sought to tabulate statistics on the generalized use of the technology in the US dairy herd and determine its effectivene...

Hand-rearing and sex determination tool for the Taveta golden weaver (Ploceus castaneiceps).

PubMed

Breeding, Shawnlei; Ferrie, Gina M; Schutz, Paul; Leighty, Katherine A; Plassé, Chelle

2012-01-01

Improvements in the ability to hand-rear birds in captivity have aided zoological institutions in the sustainable management of these species, and have provided opportunities to examine their physical growth in varying conditions. Monitoring the weight gain and development of chicks is an important aspect of developing a hand-rearing protocol. In this paper we provide the institutional history for a colonial species of passerine, the Taveta golden weaver, at Disney's Animal Kingdom®, in order to demonstrate the methods of establishing a successful breeding program which largely incorporates hand-rearing in management of the population. We also tested if we could accurately predict sex of chicks using weights collected on Day 14 during the hand-rearing process. Using this tool, we were able to correctly determine sex before fledging in more than 83% of chicks. Early sex determination is important in captive species for genetic management and husbandry purposes. While genetic sexing can be expensive, we found that using growth curves to determine sex can be a reliable and cost-effective tool for population management of a colonial passerine. © 2012 Wiley Periodicals, Inc.

Sex determination of Pohnpei Micronesian kingfishers using morphological and molecular genetic techniques

USGS Publications Warehouse

Kesler, Dylan C.; Lopes, I.F.; Haig, Susan M.

2006-01-01

Conservation-oriented studies of Micronesian Kingfishers (Todiramphus cinnamominus) have been hindered by a lack of basic natural history information, despite the status of the Guam subspecies (T. c. cinnamominus) as one of the most endangered species in the world. We used tissue samples and morphometric measures from museum specimens and wild-captured Pohnpei Micronesian Kingfishers (T. c. reichenbachii) to develop methods for sex determination. We present a modified molecular protocol and a discriminant function that yields the probability that a particular individual is male or female. Our results revealed that females were significantly larger than males, and the discriminant function correctly predicted sex in 73% (30/41) of the individuals. The sex of 86% (18/21) of individuals was correctly assigned when a moderate reliability threshold was set. Sex determination using molecular genetic techniques was more reliable than methods based on morphology. Our results will facilitate recovery efforts for the critically endangered Guam Micronesian Kingfisher and provide a basis for sex determination in the 11 other endangered congeners in the Pacific Basin.

Gender perceptions predict sex differences in growth patterns of indigenous Guatemalan infants and young children.

PubMed

Tumilowicz, Alison; Habicht, Jean-Pierre; Pelto, Gretel; Pelletier, David L

2015-11-01

Nearly one-half of Guatemalan children experience growth faltering, more so in indigenous than in nonindigenous children. On the basis of ethnographic interviews in Totonicapán, Guatemala, which revealed differences in maternal perceptions about food needs in infant girls and boys, we predicted a cumulative sex difference in favor of girls that occurred at ∼6 mo of age and diminished markedly thereafter. We examined whether the predicted differences in age-sex patterns were observed in the village, replicated the examination nationally for indigenous children, and examined whether the pattern in nonindigenous children was different. Ethnographic interviews (n = 24) in an indigenous village were conducted. Anthropometric measurements of the village children aged 0-35 mo (n = 119) were obtained. National-level growth patterns were analyzed for indigenous (n = 969) and nonindigenous (n = 1374) children aged 0-35 mo with the use of Demographic and Health Survey (DHS) data. Mothers reported that, compared with female infants, male infants were hungrier, were not as satisfied with breastfeeding alone, and required earlier complementary feeding. An anthropometric analysis confirmed the prediction of healthier growth in indigenous girls than in indigenous boys throughout the first year of life, which resulted in a 2.98-cm height-for-age difference (HAD) between sexes in the village and a 1.61-cm HAD (P < 0.001) in the DHS data between 6 and 17 mo of age in favor of girls. In both data sets, the growth sex differences diminished in the second year of life (P < 0.05). No such pattern was seen in nonindigenous children. We propose that the differences in the HAD that first favor girls and then favor boys in the indigenous growth patterns are due to feeding patterns on the basis of gendered cultural perceptions. Circumstances that result in differential sex growth patterns need to be elucidated, in particular the favorable growth in girls in the first year of life. © 2015 American Society for Nutrition.

The ZW sex microchromosomes of an Australian dragon lizard share no homology with those of other reptiles or birds.

PubMed

Ezaz, Tariq; Moritz, Benjamin; Waters, Paul; Marshall Graves, Jennifer A; Georges, Arthur; Sarre, Stephen D

2009-01-01

Reptiles show a diverse array of sex chromosomal systems but, remarkably, the Z sex chromosomes of chicken are homologous to the ZW sex chromosomes of a species of gecko, Gekko hokouensis, suggesting an ancient but common origin. This is in contrast to the ZW sex chromosomes of snakes and a species of soft-shelled turtle, Pelodiscus sinensis, which are nonhomologous to those of chicken or each other and appear to have been independently derived. In this paper, we determine what homology, if any, the sex chromosomes of the Australian dragon lizard Pogona vitticeps shares with those of snake and chicken by mapping the dragon homologs of five snake Z chromosome genes (WAC, KLF6, TAX1BP1, RAB5A, and CTNNB1) and five chicken Z chromosome genes (ATP5A1, GHR, DMRT1, CHD1, and APTX) to chromosomes in the dragon. The dragon homologs of snake and chicken sex chromosome genes map to chromosomes 6 and chromosome 2, respectively, in the dragon and that DMRT1, the bird sex-determining gene, is not located on the sex chromosomes of P. vitticeps. Indeed, our data show that the dragon homolog to the chicken Z chromosome is likely to be wholly contained within chromosome 2 in P. vitticeps, which suggests that the sex-determining factor in P. vitticeps is not the sex-determining gene of chicken. Homology between chicken Z chromosome and G. hokouensis ZW chromosome pairs has been interpreted as retention of ancient ZW sex chromosomes in which case the nonhomologous sex chromosomes of snake and dragons would be independently derived. Our data add another case of independently derived sex chromosomes in a squamate reptile, which makes retention of ancient sex chromosome homology in the squamates less plausible. Alternatively, the conservation between the bird Z chromosome and the G. hokouensis ZW chromosomes pairs is coincidental, may be an example of convergent evolution, its status as the Z chromosome having been independently derived in birds and G. hokouensis.

Korean medicine in Kazakhstan: Ideas, practices and patients.

PubMed

Penkala-Gawecka, Danuta

2002-01-01

Since the 1990s, after gaining independence by the Republic of Kazakhstan, various complementary therapies have grown rapidly there. Korean medicine in its several forms belongs among them. There is an important population of Korean deportees from Stalinist times, but this paper will show that the various forms of Korean medicine practised in Almaty, Kazakhstan's former capital, do not primarily cater for ethnic Koreans. Rather, as the paper demonstrates, it is important to see that there are different forms of Korean medicine attractive to clientele from different strata of society. Thus, there are, apart from the most traditional treatment practised at the Korean-Kazakhstani clinic in Almaty, two other newly invented modifications of Korean medicine: soo-jok and soo-ji . The paper embeds Korean medicine into the context of the drastic deterioration of the state health care system and general dissatisfaction with its services, on the one hand, and a generally supportive attitude of government authorities to complementary medicine, on the other. My empirical data suggest that in Kazakhstan people of different ethnic background, sex, age and education choose complementary therapies. The growing popularity of these therapies is not only attributed to public confidence in the methods that are perceived as 'traditional' but more importantly to the extremely difficult economic conditions which have made people search for cheaper treatment. The paper presents data that are critical of a purely culturalist interpretation of explaining the arrival of Korean medicine in Kazakhstan and suggests that it is the political economy of Korean medicine as a non-costly therapy which has made it attractive to a wide range of clients.

Sex-specific differences in the synaptonemal complex in the genus Oreochromis (Cichlidae).

PubMed

Campos-Ramos, Rafael; Harvey, Simon C; Penman, David J

2009-04-01

Total synaptonemal complex (SC) lengths were estimated from Oreochromis aureus Steindachner (which has a WZ/ZZ sex determination system), O. mossambicus Peters and O. niloticus L. (both of which have XX/XY sex determination systems). The total SC length in oocytes was greater than that in spermatocytes in all three species (194 +/- 30 microm and 134 +/- 13 microm, 187 +/- 22 microm and 127 +/- 17 microm, 193 +/- 37 microm and 144 +/- 19 microm, respectively). These sex-specific differences did not appear to be influenced by the type of sex determination system (the female/male total SC length ratio was 1.45 in O. aureus, 1.47 in O. mossambicus and 1.34 in O. niloticus) and do not correlate with the lack of any overall sex-specific length differences in the current Oreochromis linkage map. Although based on data from relatively few species, there appears to be no consistent relationship between sex-specific SC lengths and linkage map lengths in fish. Neomale (hormonally masculinized genetic female) O. aureus and O. mossambicus had total SC lengths of 138 +/- 13 microm and 146 +/- 13 microm respectively, more similar to normal males than to normal females. These findings agree with data from other vertebrate species that suggest that phenotypic sex, rather than genotype, determines traits such as total SC length, chiasmata position and recombination pattern, at least for the autosomes.

nr0b1 (DAX1) mutation in zebrafish causes female-to-male sex reversal through abnormal gonadal proliferation and differentiation.

PubMed

Chen, Sijie; Zhang, Hefei; Wang, Fenghua; Zhang, Wei; Peng, Gang

2016-09-15

Sex determinations are diverse in vertebrates. Although many sex-determining genes and pathways are conserved, the mechanistic roles of these genes and pathways in the genetic sex determination are not well understood. DAX1 (encoded by the NR0B1 gene) is a vertebrate specific orphan nuclear receptor that regulates gonadal development and sexual determination. In human, duplication of the NR0B1 gene leads to male-to-female sex reversal. In mice, Nr0b1 shows both pro-testis and anti-testis functions. We generated inheritable nr0b1 mutation in the zebrafish and found the nr0b1 mutation caused homozygous mutants to develop as fertile males due to female-to-male sex reversal. The nr0b1 mutation did not increase Caspase-3 labeling nor tp53 expression in the developing gonads. Introduction of a tp53 mutation into the nr0b1 mutant did not rescue the sex-reversal phenotype. Further examination revealed reduction in cell proliferation and abnormal somatic cell differentiation in the nr0b1 mutant gonads at the undifferentiated and bi-potential ovary stages. Together, our results suggest nr0b1 regulates somatic cell differentiation and cell proliferation to ensure normal sex development in the zebrafish. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Predicted sex ratio of juvenile Hawksbill Seaturtles inhabiting Buck Island Reef national monument, U.S. Virgin Islands

USGS Publications Warehouse

Geis, A.; Wibbels, T.; Phillips, B.; Hillis-Starr, Z.; Meylan, A.; Meylan, P.; Diez, C.; Van Dam, R.

2003-01-01

Hawksbill Seaturtles have temperature-dependent sex determination. As such, the resulting sex ratios are of conservational and ecological significance. Buck Island Reef is an interesting location for sex ratio studies since it represents a natural and unexploited foraging ground for hawksbills in the Caribbean. To examine sex ratios, blood samples were obtained from juvenile Hawksbill Seaturtles captured on Buck Island Reef over a four-year period. We used a radioimmunoassay to determine testosterone levels in those samples and compared those values to testosterone levels of juvenile hawksbills from the Caribbean whose sex has been verified by laparoscopy. The results of this study reveal a significantly female-biased sex ratio (approximately 80% female) occurs in this juvenile aggregation inhabiting Buck Island Reef.

Sex Chromosome Evolution, Heterochiasmy, and Physiological QTL in the Salmonid Brook Charr Salvelinus fontinalis

PubMed Central

Sutherland, Ben J.G.; Rico, Ciro; Audet, Céline; Bernatchez, Louis

2017-01-01

Whole-genome duplication (WGD) can have large impacts on genome evolution, and much remains unknown about these impacts. This includes the mechanisms of coping with a duplicated sex determination system and whether this has an impact on increasing the diversity of sex determination mechanisms. Other impacts include sexual conflict, where alleles having different optimums in each sex can result in sequestration of genes into nonrecombining sex chromosomes. Sex chromosome development itself may involve sex-specific recombination rate (i.e., heterochiasmy), which is also poorly understood. The family Salmonidae is a model system for these phenomena, having undergone autotetraploidization and subsequent rediploidization in most of the genome at the base of the lineage. The salmonid master sex determining gene is known, and many species have nonhomologous sex chromosomes, putatively due to transposition of this gene. In this study, we identify the sex chromosome of Brook Charr Salvelinus fontinalis and compare sex chromosome identities across the lineage (eight species and four genera). Although nonhomology is frequent, homologous sex chromosomes and other consistencies are present in distantly related species, indicating probable convergence on specific sex and neo-sex chromosomes. We also characterize strong heterochiasmy with 2.7-fold more crossovers in maternal than paternal haplotypes with paternal crossovers biased to chromosome ends. When considering only rediploidized chromosomes, the overall heterochiasmy trend remains, although with only 1.9-fold more recombination in the female than the male. Y chromosome crossovers are restricted to a single end of the chromosome, and this chromosome contains a large interspecific inversion, although its status between males and females remains unknown. Finally, we identify quantitative trait loci (QTL) for 21 unique growth, reproductive, and stress-related phenotypes to improve knowledge of the genetic architecture of these traits important to aquaculture and evolution. PMID:28626004

Interpreting contact angle results under air, water and oil for the same surfaces

NASA Astrophysics Data System (ADS)

Ozkan, Orkun; Yildirim Erbil, H.

2017-06-01

Under-water and under-oil superhydropobicity and superhydrophilicity have gained significant attention over the last few years. In this study, contact angles on five flat surfaces (polypropylene, poly(methyl methacrylate), polycarbonate, TEFLON-FEP and glass slide) were measured in water drop-in-air, air bubble-under-water, oil drop-in-air, air bubble-under-oil, oil drop-under-water and water drop-under-oil conditions. Heptane, octane, nonane, decane, dodecane, and hexadecane hydrocarbons were used as oils. Immiscible water/oil pairs were previously mutually saturated to provide thermodynamical equilibrium conditions and their surface and interfacial tensions were determined experimentally. These pairs were used in the two-liquid contact angle measurements. Surface free energies of the solid surfaces in air were determined independently by using the van Oss-Good method, using the contact angle results of pure water, ethylene glycol, formamide, methylene iodide and α-bromonaphalene. In addition, Zisman’s ‘critical surface tension’ values were also determined for comparison. In theory, the summation of contact angle results in a complementary case would give a total of 180° for ideal surfaces. However, it was determined that there are large deviations from this rule in practical cases and these deviations depend on surface free energies of solids. Three complementary cases of (water-in-air with air bubble-under-water); (oil-in-air with air bubble-under-oil); and (oil-under-water with water-under-oil) were investigated in particular to determine the deviations from ideality. A novel approach, named ‘complementary hysteresis’ [γ WA(cosθ 1  -  cosθ 2) and γ OW(cosθ 6  -  cosθ 5)] was developed where γ WA and γ OW represent the interfacial tensions of water/air and oil/water, and θ 1, θ 2, θ 5, and θ 6 were the contact angles of water/air, air bubble/water, oil/water and water/oil respectively. It was experimentally determined that complementary hysteresis varies almost linearly with the surface free energy of the flat solid samples. This is the first report showing the relation of the surface free energy of a solid which is determined under-air with the contact angles obtained on the same solid in different three-phase systems.

Identification of the sex genes in an early diverged fungus.

PubMed

Idnurm, Alexander; Walton, Felicia J; Floyd, Anna; Heitman, Joseph

2008-01-10

Sex determination in fungi is controlled by a small, specialized region of the genome in contrast to the large sex-specific chromosomes of animals and some plants. Different gene combinations reside at these mating-type (MAT) loci and confer sexual identity; invariably they encode homeodomain, alpha-box, or high mobility group (HMG)-domain transcription factors. So far, MAT loci have been characterized from a single monophyletic clade of fungi, the Dikarya (the ascomycetes and basidiomycetes), and the ancestral state and evolutionary history of these loci have remained a mystery. Mating in the basal members of the kingdom has been less well studied, and even their precise taxonomic inter-relationships are still obscure. Here we apply bioinformatic and genetic mapping to identify the sex-determining (sex) region in Phycomyces blakesleeanus (Zygomycota), which represents an early branch within the fungi. Each sex allele contains a single gene that encodes an HMG-domain protein, implicating the HMG-domain proteins as an earlier form of fungal MAT loci. Additionally, one allele also contains a copy of a unique, chromosome-specific repetitive element, suggesting a generalized mechanism for the earliest steps in the evolution of sex determination and sex chromosome structure in eukaryotes.

Genetic Diversity on the Sex Chromosomes

PubMed Central

Wilson Sayres, Melissa A

2018-01-01

Abstract Levels and patterns of genetic diversity can provide insights into a population’s history. In species with sex chromosomes, differences between genomic regions with unique inheritance patterns can be used to distinguish between different sets of possible demographic and selective events. This review introduces the differences in population history for sex chromosomes and autosomes, provides the expectations for genetic diversity across the genome under different evolutionary scenarios, and gives an introductory description for how deviations in these expectations are calculated and can be interpreted. Predominantly, diversity on the sex chromosomes has been used to explore and address three research areas: 1) Mating patterns and sex-biased variance in reproductive success, 2) signatures of selection, and 3) evidence for modes of speciation and introgression. After introducing the theory, this review catalogs recent studies of genetic diversity on the sex chromosomes across species within the major research areas that sex chromosomes are typically applied to, arguing that there are broad similarities not only between male-heterogametic (XX/XY) and female-heterogametic (ZZ/ZW) sex determination systems but also any mating system with reduced recombination in a sex-determining region. Further, general patterns of reduced diversity in nonrecombining regions are shared across plants and animals. There are unique patterns across populations with vastly different patterns of mating and speciation, but these do not tend to cluster by taxa or sex determination system. PMID:29635328

The ecology and evolution of temperature-dependent reaction norms for sex determination in reptiles: a mechanistic conceptual model.

PubMed

Pezaro, Nadav; Doody, J Sean; Thompson, Michael B

2017-08-01

Sex-determining mechanisms are broadly categorised as being based on either genetic or environmental factors. Vertebrate sex determination exhibits remarkable diversity but displays distinct phylogenetic patterns. While all eutherian mammals possess XY male heterogamety and female heterogamety (ZW) is ubiquitous in birds, poikilothermic vertebrates (fish, amphibians and reptiles) exhibit multiple genetic sex-determination (GSD) systems as well as environmental sex determination (ESD). Temperature is the factor controlling ESD in reptiles and temperature-dependent sex determination (TSD) in reptiles has become a focal point in the study of this phenomenon. Current patterns of climate change may cause detrimental skews in the population sex ratios of reptiles exhibiting TSD. Understanding the patterns of variation, both within and among populations and linking such patterns with the selection processes they are associated with, is the central challenge of research aimed at predicting the capacity of populations to adapt to novel conditions. Here we present a conceptual model that innovates by defining an individual reaction norm for sex determination as a range of incubation temperatures. By deconstructing individual reaction norms for TSD and revealing their underlying interacting elements, we offer a conceptual solution that explains how variation among individual reaction norms can be inferred from the pattern of population reaction norms. The model also links environmental variation with the different patterns of TSD and describes the processes from which they may arise. Specific climate scenarios are singled out as eco-evolutionary traps that may lead to demographic extinction or a transition to either male or female heterogametic GSD. We describe how the conceptual principles can be applied to interpret TSD data and to explain the adaptive capacity of TSD to climate change as well as its limits and the potential applications for conservation and management programs. © 2016 Cambridge Philosophical Society.

A Study on Gender Preference and Awareness Regarding Prenatal Sex Determination among Antenatal Women in a Rural Area of Darjeeling District, West Bengal, India

PubMed Central

Roy, Archak

2017-01-01

Introduction Sex ratio is one of the major indicators to find the gender preferences in the community. Change in sex ratio reflects underlying socioeconomic, cultural patterns of a society. Aim The present study was conducted with the aim to find out the knowledge of antenatal women regarding the prenatal sex determination and the Pre Natal Diagnostic Techniques (PNDT) Act in a rural area along with assessing the gender preference in family among the study population. Materials and Methods A community based, descriptive, cross-sectional study was undertaken in the villages of Matigara Block of Darjeeling district of West Bengal, which serves as a field practice area of North Bengal Medical College & Hospital for two months. A total of 116 pregnant women were included and a pre designed pre tested questionnaire was used to collect the socio demographic details. The data were analysed by SPSS 20.0 software for proportions with chi-square tests. Results Knowledge of sex determination and the PNDT Act were found to be 44.82% and 18.10% among antenatal women. Knowledge regarding assessment of gender preference showed 52.58% expect a boy in this pregnancy. It was found that the determinants for gender preference were caste, sex of the last pregnancy and current gender composition. It was found that the determinants for knowledge of sex determination are age of the mother and the gravida of the mother. It was also found that the factor for the knowledge regarding the PNDT Act is age of the mother. These associations are statistically significant. Conclusion This situation calls for a strategy which includes community based awareness campaigns, women employment, education, and empowerment and by ensuring effective implementation of PNDT Act by the government so that families find it difficult to undertake sex determination. PMID:28384893

Absolute determination of single-stranded and self-complementary adeno-associated viral vector genome titers by droplet digital PCR.

PubMed

Lock, Martin; Alvira, Mauricio R; Chen, Shu-Jen; Wilson, James M

2014-04-01

Accurate titration of adeno-associated viral (AAV) vector genome copies is critical for ensuring correct and reproducible dosing in both preclinical and clinical settings. Quantitative PCR (qPCR) is the current method of choice for titrating AAV genomes because of the simplicity, accuracy, and robustness of the assay. However, issues with qPCR-based determination of self-complementary AAV vector genome titers, due to primer-probe exclusion through genome self-annealing or through packaging of prematurely terminated defective interfering (DI) genomes, have been reported. Alternative qPCR, gel-based, or Southern blotting titering methods have been designed to overcome these issues but may represent a backward step from standard qPCR methods in terms of simplicity, robustness, and precision. Droplet digital PCR (ddPCR) is a new PCR technique that directly quantifies DNA copies with an unparalleled degree of precision and without the need for a standard curve or for a high degree of amplification efficiency; all properties that lend themselves to the accurate quantification of both single-stranded and self-complementary AAV genomes. Here we compare a ddPCR-based AAV genome titer assay with a standard and an optimized qPCR assay for the titration of both single-stranded and self-complementary AAV genomes. We demonstrate absolute quantification of single-stranded AAV vector genomes by ddPCR with up to 4-fold increases in titer over a standard qPCR titration but with equivalent readout to an optimized qPCR assay. In the case of self-complementary vectors, ddPCR titers were on average 5-, 1.9-, and 2.3-fold higher than those determined by standard qPCR, optimized qPCR, and agarose gel assays, respectively. Droplet digital PCR-based genome titering was superior to qPCR in terms of both intra- and interassay precision and is more resistant to PCR inhibitors, a desirable feature for in-process monitoring of early-stage vector production and for vector genome biodistribution analysis in inhibitory tissues.

Sex-determining mechanisms in insects based on imprinting and elimination of chromosomes.

PubMed

Sánchez, L

2014-01-01

As a rule, the sex of an individual is fixed at fertilization, and the chromosomal constitution of the zygote is a direct consequence of the chromosomal constitution of the gametes. However, there are cases in which the chromosomal differences determining sex are brought about by elimination or inactivation of chromosomes in the embryo. In Sciaridae insects, all zygotes start with the XXX constitution; the loss of either 1 or 2 X chromosomes determines whether the zygote becomes XX (female) or X0 (male). In Cecydomyiidae and Collembola insects, all zygotes start with the XXXX constitution. If the embryo does not eliminate any X chromosome, this remains XXXX and develops as female, whereas if 2 X chromosomes are eliminated, the embryo becomes XX0 and develops as a male. In the coccids (scale insects), the chromosomal differences between the sexes result from either the elimination or the heterochromatinization (inactivation) of half of the chromosomes giving rise to haploid males and diploid females. The chromosomes that are eliminated or inactivated are those inherited from the father. Therefore, in the formation of the sex-determining chromosomal signal in those insects, a marking ('imprinting') process must occur in one of the parents, which determines that the chromosomes to be eliminated or inactivated are of paternal origin. In this article, the sex determination mechanism of these insects and the associated imprinting process are reviewed. © 2013 S. Karger AG, Basel.

Longevity enhances selection of environmental sex determination.

PubMed

Bull, J J; Bulmer, M G

1989-12-01

Environmental sex determination (ESD) is a mechanism in which an individual develops as male or female largely in response to some environmental effect experienced early in life. Its forms range from sex determination by egg incubation temperature in reptiles to sex determination of photoperiod in amphipods. Previous theoretical work as suggested that ESD is favored by natural selection if the fitness consequences of the early environmental experience differ for males and females, so that an individual benefits by being male under some conditions and female under others. A drawback of ESD is that it enables climatic changes to influence the population sex ratio, and such fluctuations select against ESD. This study employed numerical analyses to investigate the balance between these two opposing forces. The negative impact of climatic fluctuations appears to depend greatly on species longevity: substantial between-year fluctuations are of little consequence in selecting against ESD in long-lived species because annual sex ratio fluctuations tend to cancel and thus alter the total population sex ratio only slightly. Thus, if a species is sufficiently long-lived, extreme ESD can be maintained despite only a weak advantage. This result offers one explanation for the failure to demonstrate an advantage for the extreme forms of ESD observed in reptiles.

Insect Sex Determination Manipulated by Their Endosymbionts: Incidences, Mechanisms and Implications

PubMed Central

Kageyama, Daisuke; Narita, Satoko; Watanabe, Masaya

2012-01-01

The sex-determining systems of arthropods are surprisingly diverse. Some species have male or female heterogametic sex chromosomes while other species do not have sex chromosomes. Most species are diploids but some species, including wasps, ants, thrips and mites, are haplodiploids (n in males; 2n in females). Many of the sexual aberrations, such as sexual mosaics, sex-specific lethality and conversion of sexuality, can be explained by developmental defects including double fertilization of a binucleate egg, loss of a sex chromosome or perturbation of sex-determining gene expression, which occur accidentally or are induced by certain environmental conditions. However, recent studies have revealed that such sexual aberrations can be caused by various groups of vertically-transmitted endosymbiotic microbes such as bacteria of the genera Wolbachia, Rickettsia, Arsenophonus, Spiroplasma and Cardinium, as well as microsporidian protists. In this review, we first summarize the accumulated data on endosymbiont-induced sexual aberrations, and then discuss how such endosymbionts affect the developmental system of their hosts and what kinds of ecological and evolutionary effects these endosymbionts have on their host populations. PMID:26467955

Insect Sex Determination Manipulated by Their Endosymbionts: Incidences, Mechanisms and Implications.

PubMed

Kageyama, Daisuke; Narita, Satoko; Watanabe, Masaya

2012-02-10

The sex-determining systems of arthropods are surprisingly diverse. Some species have male or female heterogametic sex chromosomes while other species do not have sex chromosomes. Most species are diploids but some species, including wasps, ants, thrips and mites, are haplodiploids (n in males; 2n in females). Many of the sexual aberrations, such as sexual mosaics, sex-specific lethality and conversion of sexuality, can be explained by developmental defects including double fertilization of a binucleate egg, loss of a sex chromosome or perturbation of sex-determining gene expression, which occur accidentally or are induced by certain environmental conditions. However, recent studies have revealed that such sexual aberrations can be caused by various groups of vertically-transmitted endosymbiotic microbes such as bacteria of the genera Wolbachia, Rickettsia, Arsenophonus, Spiroplasma and Cardinium, as well as microsporidian protists. In this review, we first summarize the accumulated data on endosymbiont-induced sexual aberrations, and then discuss how such endosymbionts affect the developmental system of their hosts and what kinds of ecological and evolutionary effects these endosymbionts have on their host populations.

Expression of putative sex-determining genes during the thermosensitive period of gonad development in the snapping turtle, Chelydra serpentina.

PubMed

Rhen, T; Metzger, K; Schroeder, A; Woodward, R

2007-01-01

Modes of sex determination are quite variable in vertebrates. The developmental decision to form a testis or an ovary can be influenced by one gene, several genes, environmental variables, or a combination of these factors. Nevertheless, certain morphogenetic aspects of sex determination appear to be conserved in amniotes. Here we clone fragments of nine candidate sex-determining genes from the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination (TSD). We then analyze expression of these genes during the thermosensitive period of gonad development. In particular, we compare gene expression profiles in gonads from embryos incubated at a male-producing temperature to those from embryos at a female-producing temperature. Expression of Dmrt1 and Sox9 mRNA increased gradually at the male-producing temperature, but was suppressed at the female-producing temperature. This finding suggests that Dmrt1 and Sox9 play a role in testis development. In contrast, expression of aromatase, androgen receptor (Ar), and Foxl2 mRNA was constant at the male-producing temperature, but increased several-fold in embryos at the female-producing temperature. Aromatase, Ar, and Foxl2 may therefore play a role in ovary development. In addition, there was a small temperature effect on ER alpha expression with lower mRNA levels found in embryos at the female-producing temperature. Finally, Dax1, Fgf9, and SF-1 were not differentially expressed during the sex-determining period, suggesting these genes are not involved in sex determination in the snapping turtle. Comparison of gene expression profiles among amniotes indicates that Dmrt1 and Sox9 are part of a core testis-determining pathway and that Ar, aromatase, ER alpha, and Foxl2 are part of a core ovary-determining pathway. 2007 S. Karger AG, Basel

Fatty Acids Regulate Germline Sex Determination through ACS-4-Dependent Myristoylation.

PubMed

Tang, Hongyun; Han, Min

2017-04-20

Fat metabolism has been linked to fertility and reproductive adaptation in animals and humans, and environmental sex determination potentially plays a role in the process. To investigate the impact of fatty acids (FA) on sex determination and reproductive development, we examined and observed an impact of FA synthesis and mobilization by lipolysis in somatic tissues on oocyte fate in Caenorhabditis elegans. The subsequent genetic analysis identified ACS-4, an acyl-CoA synthetase and its FA-CoA product, as key germline factors that mediate the role of FA in promoting oocyte fate through protein myristoylation. Further tests indicated that ACS-4-dependent protein myristoylation perceives and translates the FA level into regulatory cues that modulate the activities of MPK-1/MAPK and key factors in the germline sex-determination pathway. These findings, including a similar role of ACS-4 in a male/female species, uncover a likely conserved mechanism by which FA, an environmental factor, regulates sex determination and reproductive development. Copyright © 2017 Elsevier Inc. All rights reserved.

Brassinosteroid control of sex determination in maize.

PubMed

Hartwig, Thomas; Chuck, George S; Fujioka, Shozo; Klempien, Antje; Weizbauer, Renate; Potluri, Devi Prasad V; Choe, Sunghwa; Johal, Gurmukh S; Schulz, Burkhard

2011-12-06

Brassinosteroids (BRs) are plant hormones that regulate growth and development. They share structural similarities with animal steroids, which are decisive factors of sex determination. BRs are known to regulate morphogenesis and environmental stress responses, but their involvement in sex determination in plants has been only speculative. We show that BRs control sex determination in maize revealed through characterization of the classical dwarf mutant nana plant1 (na1), which also feminizes male flowers. na1 plants carry a loss-of-function mutation in a DET2 homolog--a gene in the BR biosynthetic pathway. The mutant accumulates the DET2-specific substrate (24R)-24-methylcholest-4-en-3-one with a concomitant decrease of downstream BR metabolites. Treatment of wild-type maize plants with BR biosynthesis inhibitors completely mimicked both dwarf and tasselseed phenotypes of na1 mutants. Tissue-specific na1 expression in anthers throughout their development supports the hypothesis that BRs promote masculinity of the male inflorescence. These findings suggest that, in the monoecious plant maize, BRs have been coopted to perform a sex determination function not found in plants with bisexual flowers.

Improving the complementary methods to estimate evapotranspiration under diverse climatic and physical conditions

NASA Astrophysics Data System (ADS)

Anayah, F. M.; Kaluarachchi, J. J.

2014-06-01

Reliable estimation of evapotranspiration (ET) is important for the purpose of water resources planning and management. Complementary methods, including complementary relationship areal evapotranspiration (CRAE), advection aridity (AA) and Granger and Gray (GG), have been used to estimate ET because these methods are simple and practical in estimating regional ET using meteorological data only. However, prior studies have found limitations in these methods especially in contrasting climates. This study aims to develop a calibration-free universal method using the complementary relationships to compute regional ET in contrasting climatic and physical conditions with meteorological data only. The proposed methodology consists of a systematic sensitivity analysis using the existing complementary methods. This work used 34 global FLUXNET sites where eddy covariance (EC) fluxes of ET are available for validation. A total of 33 alternative model variations from the original complementary methods were proposed. Further analysis using statistical methods and simplified climatic class definitions produced one distinctly improved GG-model-based alternative. The proposed model produced a single-step ET formulation with results equal to or better than the recent studies using data-intensive, classical methods. Average root mean square error (RMSE), mean absolute bias (BIAS) and R2 (coefficient of determination) across 34 global sites were 20.57 mm month-1, 10.55 mm month-1 and 0.64, respectively. The proposed model showed a step forward toward predicting ET in large river basins with limited data and requiring no calibration.

Adaptive Sex Determination and Population Dynamics in a Brackish-water Amphipod

NASA Astrophysics Data System (ADS)

Watt, Penelope J.; Adams, Jonathan

1993-09-01

Gammarus duebeni is a sexually dimorphic amphipod with an unusual and environmentally mediated sex determining system. In seasonal populations, environmental sex determination (ESD) is selectively advantageous and males and females are produced at different times of the year, but it has been predicted that where generations overlap or the breeding season is long, ESD should no longer have a selective advantage over genetic mechanisms of sex determination and males and females should be produced simultaneously. The dynamics of a supposedly bivoltine population at Totton Marsh on the south coast of England were investigated. The field study showed that the breeding season at Totton was not in fact bivoltine but long, extending through most of the year with a short break in early summer. Population sex ratio fluctuated seasonally: this pattern appears to be the product of differences in production of males and females rather than growth or mortality. Thus, contrary to expectations, ESD does occur in this population. Photoperiod is the cue for sex determination in the laboratory, but in the field this alone could not account for the observed pattern of male and female production at Totton Marsh. Another major variable must be involved and it is proposed that it also has an influence on other G. duebeni populations.

Complementary alternative medicine use in children with type 1 diabetes mellitus in Erzurum, Turkey.

PubMed

Arýkan, Duygu; Sívríkaya, Sibel Karaca; Olgun, Nermin

2009-08-01

The aims of this study were: (i) to determine the types of complementary and alternative medicine use among children with type I diabetes mellitus as reported by parents and (ii) to describe sociodemographic and medical factors associated with the use of such treatments in families residing in Eastern Turkey. Type 1 diabetes mellitus is a tremendously challenging and complex disease for children and families to manage. Therefore, the use of complementary and alternative medicines among children with type 1 diabetes is becoming increasingly popular. Survey. Parents of 100 paediatric patients (who were diagnosed with type 1 diabetes at least 6 months prior to the study) who visited the participating paediatric endocrinology multidisciplinary centres and clinics for diabetes management were included in the study. Data were collected by using a semi-structured questionnaire. Results. Fifty-two per cent of the parents reported the use of one or more complementary alternative medicine therapies. Most such users (59.6%) were using oral herbal preparations; including morus alba (leaves) aloe vera and stinging nettle. Since we found that 78.6% of those using herbals were satisfied with their results and 69.2% were planning to continue use, it is important for healthcare providers to have relevant knowledge about complementary alternative medicine use and learn about its efficacy and effects (positive and adverse) of these treatments. Relevance to clinical practice. Botanical substitute for insulin seems unlikely, but complementary alternative treatments may provide valuable clues for the development of new oral hypoglycaemic agents and simple dietary agents. It is important for healthcare providers to have up-to-date knowledge about the use and effects of complementary alternative medicines in the outpatient clinical care setting.

Complementary feeding: clinically relevant factors affecting timing and composition.

PubMed

Krebs, Nancy F; Hambidge, K Michael

2007-02-01

Exclusive breastfeeding for the first 6 mo of life followed by optimal complementary feeding are critical public health measures for reducing and preventing morbidity and mortality in young children. Clinical factors, such as birth weight, prematurity, and illness, that affect the iron and zinc requirements of younger infants are discussed. Maternal diet and nutritional status do not have a strong effect on the mineral content of human milk, but physiologic changes in milk and the infants' status determine the dependence of the infant on complementary foods in addition to human milk to meet iron and zinc requirements after 6 mo. The nature of zinc absorption, which is suitably characterized by saturation response modeling, dictates that plant-based diets, which are low in zinc, are associated with low absolute daily absorbed zinc, which is inadequate to meet requirements. Foods with a higher zinc content, such as meats, are much more likely to be sufficient to meet dietary requirements. Current plant-based complementary feeding patterns for older fully breastfed infants in both developed and developing countries pose a risk of zinc deficiency. The strong rationale for the potential benefits of providing meat as an early complementary food, and the examples of successful intervention programs, provide potent incentives to pursue broader implementation programs, with concurrent rigorous evaluation of both efficacy and effectiveness.

[Complementary and alternative medicine: use in Montes Claros, Minas Gerais].

PubMed

Neto, Joao Felício Rodrigues; Faria, Anderson Antônio de; Figueiredo, Maria Fernanda Santos

2009-01-01

To determine prevalence of utilization and social and economic profile of those using complementary and alternative medicine in the medium sized Brazilian city of Montes Claros, MG. A transversal descriptive study was conducted. The sample of 3090 people was probabilistic, by clusters using the household as the sample unit for interview of both genders, older than 18 years. Data were collected by semi-structured questionnaires. Utilization of complementary and alternative medicine was of 8.9% when only those involving costs such as homeopathy, acupuncture, chiropractics, techniques of relaxation/ meditation and massage are considered and of 70.0%, when all therapies found were included. Prevalent were prayers to God (52.0%), popular medicines (30.9%), physical exercises (25.5%), faith healers (15.0%), popular diets (7.1%), massage (4.9%), relaxation/meditation (2.8%), homeopathy (2.4%), and groups of self-help (1.9%), chiropractics (1.7%), acupuncture (1.5%) and orthomolecular medicine (0.2%). Women, Catholic, married of higher income and education were positively associated with utilization of therapies involving expenses. Complementary and alternative medicine is used by a significant number of those interviewed. Gender, religion, marital status, income and education were positively associated with utilization of complementary and alternative medicine. Access of those with less income and education could increase the utilization of the options that involve expenses.

Accuracy of metric sex analysis of skeletal remains using Fordisc based on a recent skull collection.

PubMed

Ramsthaler, F; Kreutz, K; Verhoff, M A

2007-11-01

It has been generally accepted in skeletal sex determination that the use of metric methods is limited due to the population dependence of the multivariate algorithms. The aim of the study was to verify the applicability of software-based sex estimations outside the reference population group for which discriminant equations have been developed. We examined 98 skulls from recent forensic cases of known age, sex, and Caucasian ancestry from cranium collections in Frankfurt and Mainz (Germany) to determine the accuracy of sex determination using the statistical software solution Fordisc which derives its database and functions from the US American Forensic Database. In a comparison between metric analysis using Fordisc and morphological determination of sex, average accuracy for both sexes was 86 vs 94%, respectively, and males were identified more accurately than females. The ratio of the true test result rate to the false test result rate was not statistically different for the two methodological approaches at a significance level of 0.05 but was statistically different at a level of 0.10 (p=0.06). Possible explanations for this difference comprise different ancestry, age distribution, and socio-economic status compared to the Fordisc reference sample. It is likely that a discriminant function analysis on the basis of more similar European reference samples will lead to more valid and reliable sexing results. The use of Fordisc as a single method for the estimation of sex of recent skeletal remains in Europe cannot be recommended without additional morphological assessment and without a built-in software update based on modern European reference samples.

Sex Chromosomes and Karyotype of the (Nearly) Mythical Creature, the Gila Monster, Heloderma suspectum (Squamata: Helodermatidae)

PubMed Central

Pokorná, Martina Johnson; Rovatsos, Michail; Kratochvíl, Lukáš

2014-01-01

A wide variety of sex determination systems exist among squamate reptiles. They can therefore serve as an important model for studies of evolutionary transitions among particular sex determination systems. However, we still have only a limited knowledge of sex determination in certain important lineages of squamates. In this respect, one of the most understudied groups is the family Helodermatidae (Anguimorpha) encompassing the only two venomous species of lizards which are potentially lethal to human beings. We uncovered homomorphic ZZ/ZW sex chromosomes in the Gila monster (Heloderma suspectum) with a highly heterochromatic W chromosome. The sex chromosomes are morphologically similar to the ZZ/ZW sex chromosomes of monitor lizards (Varanidae). If the sex chromosomes of helodermatids and varanids are homologous, female heterogamety may be ancestral for the whole Anguimorpha group. Moreover, we found that the karyotype of the Gila monster consists of 2n = 36 chromosomes (14 larger metacentric chromosomes and 22 acrocentric microchromosomes). 2n = 36 is the widely distributed chromosomal number among squamates. In his pioneering works representing the only previous cytogenetic examination of the family Helodermatidae, Matthey reported the karyotype as 2n = 38 and suggested a different chromosomal morphology for this species. We believe that this was probably erroneously. We also discovered a strong accumulation of telomeric sequences on several pairs of microchromosomes in the Gila monster, which is a trait documented relatively rarely in vertebrates. These new data fill an important gap in our understanding of the sex determination and karyotype evolution of squamates. PMID:25119263

Sex determination using the Probabilistic Sex Diagnosis (DSP: Diagnose Sexuelle Probabiliste) tool in a virtual environment.

PubMed

Chapman, Tara; Lefevre, Philippe; Semal, Patrick; Moiseev, Fedor; Sholukha, Victor; Louryan, Stéphane; Rooze, Marcel; Van Sint Jan, Serge

2014-01-01

The hip bone is one of the most reliable indicators of sex in the human body due to the fact it is the most dimorphic bone. Probabilistic Sex Diagnosis (DSP: Diagnose Sexuelle Probabiliste) developed by Murail et al., in 2005, is a sex determination method based on a worldwide hip bone metrical database. Sex is determined by comparing specific measurements taken from each specimen using sliding callipers and computing the probability of specimens being female or male. In forensic science it is sometimes not possible to sex a body due to corpse decay or injury. Skeletalization and dissection of a body is a laborious process and desecrates the body. There were two aims to this study. The first aim was to examine the accuracy of the DSP method in comparison with a current visual sexing method on sex determination. A further aim was to see if it was possible to virtually utilise the DSP method on both the hip bone and the pelvic girdle in order to utilise this method for forensic sciences. For the first part of the study, forty-nine dry hip bones of unknown sex were obtained from the Body Donation Programme of the Université Libre de Bruxelles (ULB). A comparison was made between DSP analysis and visual sexing on dry bone by two researchers. CT scans of bones were then analysed to obtain three-dimensional (3D) virtual models and the method of DSP was analysed virtually by importing the models into a customised software programme called lhpFusionBox which was developed at ULB. The software enables DSP distances to be measured via virtually-palpated bony landmarks. There was found to be 100% agreement of sex between the manual and virtual DSP method. The second part of the study aimed to further validate the method by analysing thirty-nine supplementary pelvic girdles of known sex blind. There was found to be a 100% accuracy rate further demonstrating that the virtual DSP method is robust. Statistically significant differences were found in the identification of sex between researchers in the visual sexing method although both researchers identified the same sex in all cases in the manual and virtual DSP methods for both the hip bones and pelvic girdles. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Sex Differences in Concomitant Trajectories of Self-Reported Disability and Measured Physical Capacity in Older Adults

PubMed Central

Allore, Heather G.; Mendes de Leon, Carlos F.; Gahbauer, Evelyne A.; Gill, Thomas M.

2016-01-01

Background: Despite documented age-related declines in self-reported functional status and measured physical capacity, it is unclear whether these functional indicators follow similar trajectories over time or whether the patterns of change differ by sex. Methods: We used longitudinal data from 687 initially nondisabled adults, aged 70 or older, from the Precipitating Events Project, who were evaluated every 18 months for nearly 14 years. Self-reported disability was assessed with a 12-item disability scale. Physical capacity was measured using grip strength and a modified version of Short Physical Performance Battery. Hierarchical linear models estimated the intra-individual trajectory of each functional indicator and differences in trajectories’ intercept and slope by sex. Results: Self-reported disability, grip strength, and Short Physical Performance Battery score declined over 13.5 years following nonlinear trajectories. Women experienced faster accumulation of self-reported disability, but slower declines in measured physical capacity, compared with men. Trajectory intercepts revealed that women had significantly weaker grip strength and reported higher levels of disability compared with men, with no differences in starting Short Physical Performance Battery scores. These findings were robust to adjustments for differences in sociodemographic characteristics, length-of-survival, health risk factors, and chronic-disease status. Conclusions: Despite the female disadvantage in self-reported disability, older women preserve measured physical capacity better than men over time. Self-reported and measured indicators should be viewed as complementary rather than interchangeable assessments of functional status for both clinical and research purposes, especially for sex-specific comparisons. PMID:27071781

Stigma to Sage: Learning and Teaching Safer Sex Practices Among Canadian Sex Trade Workers. NALL Working Paper.

ERIC Educational Resources Information Center

Meaghan, Diane

A study interviewed 37 Canadian sex workers in 4 cities to determine how they acquire a working knowledge of safer sex practices and what that knowledge constituted. Findings indicated the vast majority exhibited high levels of knowledge and efficacy regarding safer sex practices; sex workers took the initiative to obtain information and engage in…

Cretaceous park of sex determination: sex chromosomes are conserved across iguanas

PubMed Central

Rovatsos, Michail; Pokorná, Martina; Altmanová, Marie; Kratochvíl, Lukáš

2014-01-01

Many poikilothermic vertebrate lineages, especially among amphibians and fishes, possess a rapid turnover of sex chromosomes, while in endotherms there is a notable stability of sex chromosomes. Reptiles in general exhibit variability in sex-determining systems; as typical poikilotherms, they might be expected to have a rapid turnover of sex chromosomes. However, molecular data which would enable the testing of the stability of sex chromosomes are lacking in most lineages. Here, we provide molecular evidence that sex chromosomes are highly conserved across iguanas, one of the most species-rich clade of reptiles. We demonstrate that members of the New World families Iguanidae, Tropiduridae, Leiocephalidae, Phrynosomatidae, Dactyloidae and Crotaphytidae, as well as of the family Opluridae which is restricted to Madagascar, all share homologous sex chromosomes. As our sampling represents the majority of the phylogenetic diversity of iguanas, the origin of iguana sex chromosomes can be traced back in history to the basal splitting of this group which occurred during the Cretaceous period. Iguanas thus show a stability of sex chromosomes comparable to mammals and birds and represent the group with the oldest sex chromosomes currently known among amniotic poikilothermic vertebrates. PMID:24598109

Molecular marker suggests rapid changes of sex-determining mechanisms in Australian dragon lizards.

PubMed

Ezaz, Tariq; Quinn, Alexander E; Sarre, Stephen D; O'Meally, Denis; Georges, Arthur; Graves, Jennifer A Marshall

2009-01-01

Distribution of sex-determining mechanisms across Australian agamids shows no clear phylogenetic segregation, suggesting multiple transitions between temperature-dependent (TSD) and genotypic sex determination (GSD). These taxa thus present an excellent opportunity for studying the evolution of sex chromosomes, and evolutionary transitions between TSD and GSD. Here we report the hybridization of a 3 kb genomic sequence (PvZW3) that marks the Z and W microchromosomes of the Australian central bearded dragon (Pogona vitticeps) to chromosomes of 12 species of Australian agamids from eight genera using fluorescence in-situ hybridization (FISH). The probe hybridized to a single microchromosome pair in 11 of these species, but to the tip of the long arm of chromosome pair 2 in the twelfth (Physignathus lesueurii), indicating a micro-macro chromosome rearrangement. Three TSD species shared the marked microchromosome, implying that it is a conserved autosome in related species that determine sex by temperature. C-banding identified the marked microchromosome as the heterochromatic W chromosome in two of the three GSD species. However, in Ctenophorus fordi, the probe hybridized to a different microchromosome from that shown by C-banding to be the heterochromatic W, suggesting an independent origin for the ZW chromosome pair in that species. Given the haphazard distribution of GSD and TSD in this group and the existence of at least two sets of sex microchromosomes in GSD species, we conclude that sex-determining mechanisms in this family have evolved independently, multiple times in a short evolutionary period.

Sequence and gene content of a large fragment of a lizard sex chromosome and evaluation of candidate sex differentiating gene R-spondin 1

PubMed Central

2013-01-01

Background Scant genomic information from non-avian reptile sex chromosomes is available, and for only a few lizards, several snakes and one turtle species, and it represents only a small fraction of the total sex chromosome sequences in these species. Results We report a 352 kb of contiguous sequence from the sex chromosome of a squamate reptile, Pogona vitticeps, with a ZZ/ZW sex microchromosome system. This contig contains five protein coding genes (oprd1, rcc1, znf91, znf131, znf180), and major families of repetitive sequences with a high number of copies of LTR and non-LTR retrotransposons, including the CR1 and Bov-B LINEs. The two genes, oprd1 and rcc1 are part of a homologous syntenic block, which is conserved among amniotes. While oprd1 and rcc1 have no known function in sex determination or differentiation in amniotes, this homologous syntenic block in mammals and chicken also contains R-spondin 1 (rspo1), the ovarian differentiating gene in mammals. In order to explore the probability that rspo1 is sex determining in dragon lizards, genomic BAC and cDNA clones were mapped using fluorescence in situ hybridisation. Their location on an autosomal microchromosome pair, not on the ZW sex microchromosomes, eliminates rspo1 as a candidate sex determining gene in P. vitticeps. Conclusion Our study has characterized the largest contiguous stretch of physically mapped sex chromosome sequence (352 kb) from a ZZ/ZW lizard species. Although this region represents only a small fraction of the sex chromosomes of P. vitticeps, it has revealed several features typically associated with sex chromosomes including the accumulation of large blocks of repetitive sequences. PMID:24344927

Chromosome chains and platypus sex: kinky connections.

PubMed

Ashley, Terry

2005-07-01

Mammal sex determination depends on an XY chromosome system, a gene for testis development and a means of activating the X chromosome. The duckbill platypus challenges these dogmas.(1,2) Gutzner et al.(1) find no recognizable SRY sequence and question whether the mammalian X was even the original sex chromosome in the platypus. Instead they suggest that the original platypus sex chromosomes were derived from the ZW chromosome system of birds and reptiles. Unraveling the puzzles of sex determination and dosage compensation in the platypus has been complicated by the fact that it has a surplus of sex chromosomes. Rather than a single X and Y chromosome, the male platypus has five Xs and five Ys. Copyright (c) 2005 Wiley Periodicals, Inc.

Multilocus Sex Determination Revealed in Two Populations of Gynodioecious Wild Strawberry, Fragaria vesca subsp. bracteata

PubMed Central

Ashman, Tia-Lynn; Tennessen, Jacob A.; Dalton, Rebecca M.; Govindarajulu, Rajanikanth; Koski, Matthew H.; Liston, Aaron

2015-01-01

Gynodioecy, the coexistence of females and hermaphrodites, occurs in 20% of angiosperm families and often enables transitions between hermaphroditism and dioecy. Clarifying mechanisms of sex determination in gynodioecious species can thus illuminate sexual system evolution. Genetic determination of gynodioecy, however, can be complex and is not fully characterized in any wild species. We used targeted sequence capture to genetically map a novel nuclear contributor to male sterility in a self-pollinated hermaphrodite of Fragaria vesca subsp. bracteata from the southern portion of its range. To understand its interaction with another identified locus and possibly additional loci, we performed crosses within and between two populations separated by 2000 km, phenotyped the progeny and sequenced candidate markers at both sex-determining loci. The newly mapped locus contains a high density of pentatricopeptide repeat genes, a class commonly involved in restoration of fertility caused by cytoplasmic male sterility. Examination of all crosses revealed three unlinked epistatically interacting loci that determine sexual phenotype and vary in frequency between populations. Fragaria vesca subsp. bracteata represents the first wild gynodioecious species with genomic evidence of both cytoplasmic and nuclear genes in sex determination. We propose a model for the interactions between these loci and new hypotheses for the evolution of sex determining chromosomes in the subdioecious and dioecious Fragaria. PMID:26483011

The lesser known challenge of climate change: thermal variance and sex-reversal in vertebrates with temperature-dependent sex determination.

PubMed

Neuwald, Jennifer L; Valenzuela, Nicole

2011-03-23

Climate change is expected to disrupt biological systems. Particularly susceptible are species with temperature-dependent sex determination (TSD), as in many reptiles. While the potentially devastating effect of rising mean temperatures on sex ratios in TSD species is appreciated, the consequences of increased thermal variance predicted to accompany climate change remain obscure. Surprisingly, no study has tested if the effect of thermal variance around high-temperatures (which are particularly relevant given climate change predictions) has the same or opposite effects as around lower temperatures. Here we show that sex ratios of the painted turtle (Chrysemys picta) were reversed as fluctuations increased around low and high unisexual mean-temperatures. Unexpectedly, the developmental and sexual responses around female-producing temperatures were decoupled in a more complex manner than around male-producing values. Our novel observations are not fully explained by existing ecological models of development and sex determination, and provide strong evidence that thermal fluctuations are critical for shaping the biological outcomes of climate change.

Epigenetic-induced alterations in sex-ratios in response to climate change: An epigenetic trap?

PubMed

Consuegra, Sofia; Rodríguez López, Carlos M

2016-10-01

We hypothesize that under the predicted scenario of climate change epigenetically mediated environmental sex determination could become an epigenetic trap. Epigenetically regulated environmental sex determination is a mechanism by which species can modulate their breeding strategies to accommodate environmental change. Growing evidence suggests that epigenetic mechanisms may play a key role in phenotypic plasticity and in the rapid adaptation of species to environmental change, through the capacity of organisms to maintain a non-genetic plastic memory of the environmental and ecological conditions experienced by their parents. However, inherited epigenetic variation could also be maladaptive, becoming an epigenetic trap. This is because environmental sex determination can alter sex ratios by increasing the survival of one of the sexes at the expense of negative fitness consequences for the other, which could lead not only to the collapse of natural populations, but also have an impact in farmed animal and plant species. © 2016 WILEY Periodicals, Inc.

An Ecological Approach Toward Prevention and Care of Victims of Domestic Minor Sex Trafficking.

PubMed

Sanchez, Rosario V; Pacquiao, Dula F

Sex trafficking is a widespread form of human trafficking that exists globally. The forced sexual exploitation of young women for profit at the hands of traffickers is a human rights violation. Sex trafficking is a form of modern-day slavery where youths are sold as a commodity. It is difficult to determine the wide range of negative health outcomes associated with domestic minor sex trafficking due to the hidden nature of the crime and its lack of statistical data to determine prevalence. Viewing domestic minor sex trafficking through an ecological lens assists in the understanding of the multiple complex interactions between victims, their relationships, and environments that influence their health. Forensic nurses are poised as experts in the healthcare of vulnerable populations and possess the knowledge to understand that social determinants of vulnerability depend on the distinct setting or environment where victims of sex trafficking reside and how different factors affect their victimology, resilience, and well-being.

A Test of the DSP Sexing Method on CT Images from a Modern French Sample.

PubMed

Mestekova, Sarka; Bruzek, Jaroslav; Veleminska, Jana; Chaumoitre, Kathia

2015-09-01

The hip bone is considered to be one of the most reliable indicators in sex determination. The aim of this study was to test the reliability of the DSP method for the hip bone proposed by Murail et al. (Bull Mem Soc Anthropol Paris, 17, 2005, 167) on a sample from a present-day population in France (52 males and 54 females). Ten linear measurements were collected from three-dimensional models derived from computed tomography images (CTI). To quantify the proportions of correct sex determinations, a more rigorous posterior probability threshold of 0.95 was applied. Using all 10 measurements, 92.3% of males and 97.2% of females were sexed correctly. The percentage of undetermined specimens varied depending on the used combination of measurements; however, all sexes were assigned with a 100% accuracy. This study proves that DSP is an appropriate and reliable tool for sex determination, based on dimensions obtained from CTI. © 2015 American Academy of Forensic Sciences.

Sexual dimorphism in mammalian autosomal gene regulation is determined not only by Sry but by sex chromosome complement as well.

PubMed

Wijchers, Patrick J; Yandim, Cihangir; Panousopoulou, Eleni; Ahmad, Mushfika; Harker, Nicky; Saveliev, Alexander; Burgoyne, Paul S; Festenstein, Richard

2010-09-14

Differences between males and females are normally attributed to developmental and hormonal differences between the sexes. Here, we demonstrate differences between males and females in gene silencing using a heterochromatin-sensitive reporter gene. Using "sex-reversal" mouse models with varying sex chromosome complements, we found that this differential gene silencing was determined by X chromosome complement, rather than sex. Genome-wide transcription profiling showed that the expression of hundreds of autosomal genes was also sensitive to sex chromosome complement. These genome-wide analyses also uncovered a role for Sry in modulating autosomal gene expression in a sex chromosome complement-specific manner. The identification of this additional layer in the establishment of sexual dimorphisms has implications for understanding sexual dimorphisms in physiology and disease. Copyright © 2010 Elsevier Inc. All rights reserved.

Determination of age, sex, and blood group from a single tooth.

PubMed

Nayar, Amit K; Parhar, Swati; Thind, Gagandeep; Sharma, Aman; Sharma, Divya

2017-01-01

Human identification is one of the most challenging subjects that human has been confronted with. Through the ages, odontological examinations have been a critical determinant in the search of human identity. Data in the form of age, gender, and blood group might provide vital clues in such investigations. In the recent times, it has been often desirable to preserve tissues for further investigations following the unfolding of certain events or discovery of new data. Hence, it is important to gather as much data as possible using less tissue. The purpose of this study was to determine age, sex, and ABO blood group of individual from a single tooth, to determine the effect of different environmental conditions, and to extract maximum information also at the same time preserving some tissue for the further investigation whenever needed. The study sample consisted of sixty teeth divided into four groups under different environmental conditions and time. The teeth were sectioned longitudinally in the buccolingual plane along the midline. Longitudinal ground sections of each tooth were prepared for age determination from cemental lines. Pulp removed was divided into two halves thereafter sex and blood group was determined. For correlation of age between estimated age and actual age, using cemental lines Pearson's correlation coefficient was applied. Further for determination of both sex and blood group between groups, Chi-square test was applied. A strong positive correlation was found between the estimated age and actual age of the study groups. Moreover, there was no significant difference between the actual and determined sex and blood group of the study groups. Although age, sex, and blood group are more reliably determined in freshly extracted teeth, these variables may be of significant help in identification even after a period of 6 weeks postextraction.

Timely initiation of complementary feeding and associated factors among children aged 6 to 12 months in Northern Ethiopia: an institution-based cross-sectional study

PubMed Central

2013-01-01

Background Exclusive breastfeeding (EBF) for the first six months of life is critical for the wellbeing of the child. In the mean while, timely initiation and starting nutritionally-adequate, safe, age-appropriate complementary feeding at six months is recommended for the better health and development of infants. According to the Ethiopian Demographic and Health Survey 2011, timely initiation of complementary feeding in Ethiopia at the 6th month was only 51%. The purpose of this study is to determine the magnitude of timely initiation of complementary feeding and associated factors in Mekelle town, Northern Ethiopia. Methods An institutional based cross-sectional study design was conducted among 422 mothers of infants aged from six months to one year selected from six public health facilities. Sample size proportional to the patient flow rate of each institution was allocated and systematic random sampling method was used to get the study participant. An exit interview using structured questionnaire was conducted about their experience on complementary feeding and related experience. The questionnaire was pretested among 21 mothers. Data were entered with EPI info version 3.5.1 and cleaning and analysis was done by using SPSS version 16. Frequencies distribution, binary and multiple logistic regressions were done. OR and 95% confidence interval was computed. Result The prevalence of timely initiation of complementary feeding at sixth month was 62.8% (265/422, 95% C.I: 58.1, 67.31%). Educational level, occupation of mother, parity, having ANC follow up, and birth preparedness were found to be independent predictor of timely initiation of complementary feeding. Conclusions Almost two-third of mothers initiated complementary feeding at six month of child’ age as recommended. This was relatively higher prevalence than most developing countries. However, significant proportion of mothers still did not initiate complementary feeding timely. Mothers who are illiterate and completed only primary school need more attention. All mothers must be encouraged to make antenatal care follow up. PMID:24195592

Sex determination in the wild: a field application of loop-mediated isothermal amplification successfully determines sex across three raptor species.

PubMed

Centeno-Cuadros, A; Abbasi, I; Nathan, R

2017-03-01

PCR-based methods are the most common technique for sex determination of birds. Although these methods are fast, easy and accurate, they still require special facilities that preclude their application outdoors. Consequently, there is a time lag between sampling and obtaining results that impedes researchers to take decisions in situ and in real time considering individuals' sex. We present an outdoor technique for sex determination of birds based on the amplification of the duplicated sex-chromosome-specific gene Chromo-Helicase-DNA binding protein using a loop-mediated isothermal amplification (LAMP). We tested our method on Griffon Vulture (Gyps fulvus), Egyptian Vulture (Neophron percnopterus) and Black Kite (Milvus migrans) (family Accipitridae). We introduce the first fieldwork procedure for sex determination of animals in the wild, successfully applied to raptor species of three different subfamilies using the same specific LAMP primers. This molecular technique can be deployed directly in sampling areas because it only needs a voltage inverter to adapt a thermo-block to a car lighter and results can be obtained by the unaided eye based on colour change within the reaction tubes. Primers and reagents are prepared in advance to facilitate their storage at room temperature. We provide detailed guidelines how to implement this procedure, which is simpler (no electrophoresis required), cheaper and faster (results in c. 90 min) than PCR-based laboratory methods. Our successful cross-species application across three different raptor subfamilies posits our set of markers as a promising tool for molecular sexing of other raptor families and our field protocol extensible to all bird species. © 2016 John Wiley & Sons Ltd.

Steroid signaling system responds differently to temperature and hormone manipulation in the red-eared slider turtle (Trachemys scripta elegans), a reptile with temperature-dependent sex determination.

PubMed

Ramsey, M; Crews, D

2007-01-01

Many reptiles, including the red-eared slider turtle (Trachemys scripta elegans), exhibit temperature-dependent sex determination (TSD). Temperature determines gonadal sex during the middle of embryogenesis, or the temperature-sensitive period (TSP), when gonadal sex is labile to both temperature and hormones--particularly estrogen. The biological actions of steroid hormones are mediated by their receptors as defined here as the classic transcriptional regulation of target genes. To elucidate estrogen action during sex determination, we examined estrogen receptor alpha (Esr1, hereafter referred to as ERalpha), estrogen receptor beta (Esr2, hereafter referred to as ERbeta), and androgen receptor (Ar, hereafter referred to as AR) expression in slider turtle gonads before, during and after the TSP, as well as following sex reversal via temperature or steroid hormone manipulation. ERalpha and AR levels spike at the female-producing temperature while ovarian sex is determined, but none of the receptors exhibited sexually dimorphic localization within the gonad prior to morphological differentiation. All three receptors respond differentially to sex-reversing treatments. When shifted to female-producing temperatures, embryos maintain ERalpha and AR expression while ERbeta is reduced. When shifted to male-producing temperatures, medullary expression of all three receptors is reduced. Feminization via estradiol (E(2)) treatment at a male-producing temperature profoundly changed the expression patterns for all three receptors. ERalpha and ERbeta redirected to the cortex in E(2)-created ovaries, while AR medullary expression was transiently reduced. Although warmer incubation temperature and estrogen result in the same endpoint (ovarian development), our results indicate different steroid signaling patterns between temperature- and estrogen-induced feminization. 2007 S. Karger AG, Basel

Transcriptome Profile Analysis from Different Sex Types of Ginkgo biloba L.

PubMed

Du, Shuhui; Sang, Yalin; Liu, Xiaojing; Xing, Shiyan; Li, Jihong; Tang, Haixia; Sun, Limin

2016-01-01

In plants, sex determination is a comprehensive process of correlated events, which involves genes that are differentially and/or specifically expressed in distinct developmental phases. Exploring gene expression profiles from different sex types will contribute to fully understanding sex determination in plants. In this study, we conducted RNA-sequencing of female and male buds (FB and MB) as well as ovulate strobilus and staminate strobilus (OS and SS) of Ginkgo biloba to gain insights into the genes potentially related to sex determination in this species. Approximately 60 Gb of clean reads were obtained from eight cDNA libraries. De novo assembly of the clean reads generated 108,307 unigenes with an average length of 796 bp. Among these unigenes, 51,953 (47.97%) had at least one significant match with a gene sequence in the public databases searched. A total of 4709 and 9802 differentially expressed genes (DEGs) were identified in MB vs. FB and SS vs. OS, respectively. Genes involved in plant hormone signal and transduction as well as those encoding DNA methyltransferase were found to be differentially expressed between different sex types. Their potential roles in sex determination of G. biloba were discussed. Pistil-related genes were expressed in male buds while anther-specific genes were identified in female buds, suggesting that dioecism in G. biloba was resulted from the selective arrest of reproductive primordia. High correlation of expression level was found between the RNA-Seq and quantitative real-time PCR results. The transcriptome resources that we generated allowed us to characterize gene expression profiles and examine differential expression profiles, which provided foundations for identifying functional genes associated with sex determination in G. biloba.

Expression analysis of Drosophila doublesex, transformer-2, intersex, fruitless-like, and vitellogenin homologs in the parahaploid predator Metaseiulus occidentalis (Chelicerata: Acari: Phytoseiidae).

PubMed

Pomerantz, Aaron F; Hoy, Marjorie A

2015-01-01

Characterization and expression analyses are essential to gain insight into sex-determination pathways in members of the Acari. Little is known about sex determination at the molecular level in the western orchard predatory mite Metaseiulus occidentalis (Arthropoda: Chelicerata: Arachnida: Acari: Phytoseiidae), a parahaploid species. In this study, eight genes previously identified as putative homologs to genes involved in the sex-determination pathway in Drosophila melanogaster were evaluated for sex-specific alternative splicing and sex-biased expression using reverse-transcriptase PCR and quantitative real-time PCR techniques, respectively. The homologs evaluated in M. occidentalis included two doublesex-like genes (Moccdsx1 and Moccdsx2), transformer-2 (Mocctra-2), intersex (Moccix), two fruitless-like genes (MoccBTB1 and MoccBTB2), as well as two vitellogenin-like genes (Moccvg1 and Moccvg2). Single transcripts of equal size were detected in males and females for Moccdsx1, Moccdsx2, Mocctra-2, Moccix, and MoccBTB2, suggesting that their pre-mRNAs do not undergo alternative splicing in a sex-specific manner. Three genes, Moccdsx1, Moccdsx2 and MoccBTB2, displayed male-biased expression relative to females. One gene, Moccix, displayed female-biased expression relative to males. Two genes, Mocctra-2 and MoccBTB1, did not display detectable differences in transcript abundance in males and females. Expression of Moccvg1 and Moccvg2 were detected in females only, and transcript levels were up-regulated in mated females relative to unmated females. To our knowledge, this represents the first attempt to elucidate expression patterns of putative sex-determination genes in an acarine. This study is an initial step towards understanding the sex-determination pathway in the parahaploid M. occidentalis.

Transcriptome Profile Analysis from Different Sex Types of Ginkgo biloba L.

PubMed Central

Du, Shuhui; Sang, Yalin; Liu, Xiaojing; Xing, Shiyan; Li, Jihong; Tang, Haixia; Sun, Limin

2016-01-01

In plants, sex determination is a comprehensive process of correlated events, which involves genes that are differentially and/or specifically expressed in distinct developmental phases. Exploring gene expression profiles from different sex types will contribute to fully understanding sex determination in plants. In this study, we conducted RNA-sequencing of female and male buds (FB and MB) as well as ovulate strobilus and staminate strobilus (OS and SS) of Ginkgo biloba to gain insights into the genes potentially related to sex determination in this species. Approximately 60 Gb of clean reads were obtained from eight cDNA libraries. De novo assembly of the clean reads generated 108,307 unigenes with an average length of 796 bp. Among these unigenes, 51,953 (47.97%) had at least one significant match with a gene sequence in the public databases searched. A total of 4709 and 9802 differentially expressed genes (DEGs) were identified in MB vs. FB and SS vs. OS, respectively. Genes involved in plant hormone signal and transduction as well as those encoding DNA methyltransferase were found to be differentially expressed between different sex types. Their potential roles in sex determination of G. biloba were discussed. Pistil-related genes were expressed in male buds while anther-specific genes were identified in female buds, suggesting that dioecism in G. biloba was resulted from the selective arrest of reproductive primordia. High correlation of expression level was found between the RNA-Seq and quantitative real-time PCR results. The transcriptome resources that we generated allowed us to characterize gene expression profiles and examine differential expression profiles, which provided foundations for identifying functional genes associated with sex determination in G. biloba. PMID:27379148

Evolutionary origins of leadership and followership.

PubMed

Van Vugt, Mark

2006-01-01

Drawing upon evolutionary logic, leadership is reconceptualized in terms of the outcome of strategic interactions among individuals who are following different, yet complementary, decision rules to solve recurrent coordination problems. This article uses the vast psychological literature on leadership as a database to test several evolutionary hypotheses about the origins of leadership and followership in humans. As expected, leadership correlates with initiative taking, trait measures of intelligence, specific task competencies, and several indicators of generosity. The review finds no link between leadership and dominance. The evolutionary analysis accounts for reliable age, health, and sex differences in leadership emergence. In general, evolutionary theory provides a useful, integrative framework for studying leader-follower relationships and generates various novel research hypotheses.

Homeostatic signature of anabolic steroids in cattle using 1H-13C HMBC NMR metabonomics.

PubMed

Dumas, Marc-Emmanuel; Canlet, Cécile; Vercauteren, Joseph; André, François; Paris, Alain

2005-01-01

We used metabonomics to discriminate the urinary signature of different anabolic steroid treatments in cattle having different physiological backgrounds (age, sex, and race). (1)H-(13)C heteronuclear multiple bonding connectivity NMR spectroscopy and multivariate statistical methods reveal that metabolites such as trimethylamine-N-oxide, dimethylamine, hippurate, creatine, creatinine, and citrate characterize the biological fingerprint of anabolic treatment. These urinary biomarkers suggest an overall homeostatic adaptation in nitrogen and energy metabolism. From results obtained in this study, it is now possible to consider metabonomics as a complementary method usable to improve doping control strategies to detect fraudulent anabolic treatment in cattle since the oriented global metabolic response provides helpful discrimination.

Interactive effects of culture and sex hormones on the sex role self-concept

PubMed Central

Pletzer, Belinda; Petasis, Ourania; Ortner, Tuulia M.; Cahill, Larry

2015-01-01

Sex role orientation, i.e., a person's masculinity or femininity, influences cognitive and emotional performance, like biological sex. While it is now widely accepted that sex differences are modulated by the hormonal status of female participants (menstrual cycle, hormonal contraceptive use), the question, whether hormonal status and sex hormones also modulate participants sex role orientation has hardly been addressed previously. The present study assessed sex role orientation and hormonal status as well as sex hormone levels in three samples of participants from two different cultures (Northern American, Middle European). Menstrual cycle phase did not affect participant's masculinity or femininity, but had a significant impact on reference group. While women in their follicular phase (low levels of female sex hormones) determined their masculinity and femininity in reference to men, women in their luteal phase (high levels of female sex hormones) determined their masculinity and femininity in reference to women. Hormonal contraceptive users rated themselves as significantly more feminine and less masculine than naturally cycling women. Furthermore, the impact of biological sex on the factorial structure of sex role orientation as well as the relationship of estrogen to masculinity/femininity was modulated by culture. We conclude that culture and sex hormones interactively affect sex role orientation and hormonal status of participants should be controlled for when assessing masculinity and/or femininity. PMID:26236181

Sex-specific markers developed by next-generation sequencing confirmed an XX/XY sex determination system in bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix).

PubMed

Liu, Haiyang; Pang, Meixia; Yu, Xiaomu; Zhou, Ying; Tong, Jingou; Fu, Beide

2018-01-05

Sex-specific markers are powerful tools for identifying sex-determination system in various animals. Bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix) are two of the most important edible fish in Asia, which have a long juvenility period that can lasts for 4-5 years. In this study, we found one sex-specific marker by next-generation sequencing together with bioinformatics analysis in bighead carp. The male-specific markers were used to perform molecular sexing in the progenies of artificial gynogenetic diploids and found all progenies (n = 160) were females. Meanwhile, around 1 : 1 sex ratio was observed in a total of 579 juvenile offspring from three other families. To further extend the male-specific region, we performed genome walking and got a male-specific sequence of 8,661 bp. Five pairs of primers were designed and could be used to efficiently distinguish males from females in bighead carp and silver carp. The development of these male-specific markers and results of their molecular sexing in different populations provide strong evidence for a sex determination system of female homogametry or male heterogametry (XX/XY) in bighead carp and silver carp. To the best of our knowledge, this is the first report of effective sex-specific markers in these two large carp species. © The Author(s) 2018. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Odontometric sex discrimination in the Herculaneum sample (79 AD, Naples, Italy), with application to juveniles.

PubMed

Viciano, Joan; Alemán, Inmaculada; D'Anastasio, Ruggero; Capasso, Luigi; Botella, Miguel C

2011-05-01

Sex determination of subadult skeletal remains with satisfactory accuracy represents one of the most important limitations of archaeological research and forensic practice. Teeth are one of the most durable physical elements of an individual that remain after death, and constitute a potential source of information about the biological sex of that individual. This study was based on the skeletal remains of 117 individuals from the ancient city of Herculaneum (Naples, Italy), victims of the eruption of the nearby volcano Vesuvius on 24/25 August, 79 AD. It has been possible to develop discriminant function formulae based on dental dimensions of adult individuals whose sex had previously been determined based on descriptive osteologic criteria. These formulae were subsequently applied to the permanent dentitions of immature individuals of the same population in order to estimate their sex. The results show that the canine is the tooth with the greatest sex dimorphism in adults, providing percentages of correct assignment of sex between 76.5% and 100% depending on the dimension used. Of the 30 subadult individuals in the target sample, estimation of sex was possible for 22 individuals. Sex assignments matched those determined from descriptive characteristics of the ilia and mandible in 73.33% of the cases. The results provide some optimism that this method may be applicable to juvenile archaeological samples. Copyright © 2011 Wiley-Liss, Inc.

Molecular cloning and functional characterization of the sex-determination gene doublesex in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Coleoptera, Tenebrionidae)

PubMed Central

Gotoh, Hiroki; Ishiguro, Mai; Nishikawa, Hideto; Morita, Shinichi; Okada, Kensuke; Miyatake, Takahisa; Yaginuma, Toshinobu; Niimi, Teruyuki

2016-01-01

Various types of weapon traits found in insect order Coleoptera are known as outstanding examples of sexually selected exaggerated characters. It is known that the sex determination gene doublesex (dsx) plays a significant role in sex-specific expression of weapon traits in various beetles belonging to the superfamily Scarabaeoidea. Although sex-specific weapon traits have evolved independently in various Coleopteran groups, developmental mechanisms of sex-specific expression have not been studied outside of the Scarabaeoidea. In order to test the hypothesis that dsx-dependent sex-specific expression of weapon traits is a general mechanism among the Coleoptera, we have characterized the dsx in the sexually dimorphic broad-horned beetle Gnatocerus cornutus (Tenebrionidea, Tenebirionidae). By using molecular cloning, we identified five splicing variants of Gnatocerus cornutus dsx (Gcdsx), which are predicted to code four different isoforms. We found one male-specific variant (GcDsx-M), two female-specific variants (GcDsx-FL and GcDsx-FS) and two non-sex-specific variants (correspond to a single isoform, GcDsx-C). Knockdown of all Dsx isoforms resulted in intersex phenotype both in male and female. Also, knockdown of all female-specific isoforms transformed females to intersex phenotype, while did not affect male phenotype. Our results clearly illustrate the important function of Gcdsx in determining sex-specific trait expression in both sexes. PMID:27404087

Sex hormones in the cardiovascular system.

PubMed

dos Santos, Roger Lyrio; da Silva, Fabrício Bragança; Ribeiro, Rogério Faustino; Stefanon, Ivanita

2014-05-01

Gender-associated differences in the development of cardiovascular diseases have been described in humans and animals. These differences could explain the low incidence of cardiovascular disease in women in the reproductive period, such as stroke, hypertension, and atherosclerosis. The cardiovascular protection observed in females has been attributed to the beneficial effects of estrogen on endothelial function. Besides estrogen, sex hormones are able to modulate blood pressure by acting on important systems as cardiovascular, renal, and neural. They can have complementary or antagonistic actions. For example, testosterone can raise blood pressure by stimulating the renin-angiotensin-aldosterone system, whereas estrogen alone or combined with progesterone has been associated with decreased blood pressure. The effects of testosterone in the development of cardiovascular disease are contradictory. Although some researchers suggest a positive effect, others indicate negative actions of testosterone. Estrogens physiologically stimulate the release of endothelium-derived vasodilator factors and inhibit the renin-angiotensin system. Although the cardioprotective effects of estrogen are widely appreciated, little is known about the effects of progesterone, which is commonly used in hormone replacement therapy. Progesterone has both vasodilatory and vasoconstrictive effects in the vasculature, depending on the location of the vessel and the level of exposure. Nevertheless, the mechanisms through which sex hormones modulate blood pressure have not been fully elucidated. Therefore, the characterization of those could lead to a better understanding of hypertension in women and men and perhaps to improved forms of therapy.

Molecular cloning and expression of caspase-3 in the protandrous cinnamon clownfish, Amphiprion melanopus, during sex change.

PubMed

Kim, Na Na; Lee, Jehee; Habibi, Hamid R; Choi, Cheol Young

2013-06-01

The caspase-3 appears to be a key protease in the apoptotic pathway. We identified caspase-3 complementary DNAs from the ovaries of the protandrous cinnamon clownfish (Amphiprion melanopus), and investigated its mRNA and proteins, and activity levels during the sex change (I, mature male; II, male at 90 days after removing of the female; and III, mature female). The nucleotide sequence of the caspase-3 cDNA was 969 base pairs in length with open reading frames encoding peptides of 282 amino acids. The caspase-3 mRNA and protein, and activity levels in stages of the mature gonad are higher than those of the development gonad stage. To understand the effect of gonadotropin-releasing hormone (GnRH) on gonad apoptosis, we examined expression of genes caspase-3 mRNA and activity level in immature cinnamon clownfish gonads after GnRH analogue (GnRHa). The findings support the hypothesis that caspase-3 expression is associated with both testicular and ovarian development, and suggests that it may play a role in the control of ovarian development in cinnamon clownfish. Also, we demonstrate that GnRH agonists stimulate caspase-3 production which can in turn stimulate apoptosis. The present study provides a framework for better understanding of the role of caspase-3 during sex change processes in fish.

Path Complexity in Virtual Water Maze Navigation: Differential Associations with Age, Sex, and Regional Brain Volume.

PubMed

Daugherty, Ana M; Yuan, Peng; Dahle, Cheryl L; Bender, Andrew R; Yang, Yiqin; Raz, Naftali

2015-09-01

Studies of human navigation in virtual maze environments have consistently linked advanced age with greater distance traveled between the start and the goal and longer duration of the search. Observations of search path geometry suggest that routes taken by older adults may be unnecessarily complex and that excessive path complexity may be an indicator of cognitive difficulties experienced by older navigators. In a sample of healthy adults, we quantify search path complexity in a virtual Morris water maze with a novel method based on fractal dimensionality. In a two-level hierarchical linear model, we estimated improvement in navigation performance across trials by a decline in route length, shortening of search time, and reduction in fractal dimensionality of the path. While replicating commonly reported age and sex differences in time and distance indices, a reduction in fractal dimension of the path accounted for improvement across trials, independent of age or sex. The volumes of brain regions associated with the establishment of cognitive maps (parahippocampal gyrus and hippocampus) were related to path dimensionality, but not to the total distance and time. Thus, fractal dimensionality of a navigational path may present a useful complementary method of quantifying performance in navigation. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Acceptability of vaginal microbicides among female sex workers and their intimate male partners in two Mexico-U.S. border cities: a mixed methods analysis

PubMed Central

Robertson, Angela M.; Syvertsen, Jennifer L.; Martinez, Gustavo; Rangel, M. Gudelia; Palinkas, Lawrence A.; Stockman, Jamila K.; Ulibarri, Monica D.; Strathdee, Steffanie A.

2013-01-01

Background Female sex workers (FSWs) may benefit from pre-exposure prophylaxis (PrEP) including microbicides for HIV prevention. Since adherence is a key factor in PrEP efficacy, we explored microbicide acceptability and potential barriers to use within FSWs’ intimate relationships in Tijuana and Ciudad Juárez, Mexico, where HIV prevalence is increasing. Methods FSWs and their verified intimate (non-commercial) male partners completed quantitative and qualitative interviews from 2010–2012. Our complementary mixed methods design followed an iterative process to assess microbicide acceptability, explore related relationship dynamics, and identify factors associated with concern about male partners’ anger regarding microbicide use. Results Among 185 couples (n=370 individuals), interest in microbicides was high. In qualitative interviews with 28 couples, most participants were enthusiastic about microbicides for sex work contexts but some explained that microbicides could imply mistrust/infidelity within their intimate relationships. In the overall sample, nearly 1 in 6 participants (16%) worried that male partners would become angry about microbicides, which was associated with higher self-esteem among FSWs and lower self-esteem and past year conflict causing injury within relationships among men. Conclusions HIV prevention interventions should consider intimate relationship dynamics posing potential barriers to PrEP acceptability and adherence, involve male partners, and promote risk communication skills. PMID:23398385

A Duplicated, Truncated amh Gene Is Involved in Male Sex Determination in an Old World Silverside.

PubMed

Bej, Dilip Kumar; Miyoshi, Kaho; Hattori, Ricardo S; Strüssmann, Carlos A; Yamamoto, Yoji

2017-08-07

A master sex-determining gene, the Y chromosome-linked anti-Müllerian hormone ( amhy ) gene, has been described in two New World atheriniform species but little is known on the distribution, evolution, and function(s) of this gene in other Atheriniformes. Interestingly, amhy has been found to coexist with temperature-dependent sex determination (TSD), providing a unique opportunity to explore the interplay between genotypic and environmental sex determination. In this study, the search for an amhy homolog was extended to an Old World atheriniform, the cobaltcap silverside Hypoatherina tsurugae (Atherinidae). The full sequences, including the coding and noncoding regions, of the autosomal amh ( amha ) and a putative amhy were obtained. The deduced Amha and Amhy proteins comprised 511 and 340 amino acids (aa), respectively. PCR analysis with genomic DNA from wild adults and from laboratory-reared juveniles revealed a high, but not complete association of ∼95% between amhy and maleness. The spatiotemporal expression of amhy and amha during gonadal sex differentiation was analyzed by qRT-PCR and in situ hybridization (ISH). amhy transcription (in amhy -positive larvae) started before and peaked during histological differentiation of the gonads whereas amha was negligible during the same period in both genotypes. These results demonstrate that the amhy , although with some structural differences in relation to the amhy of some New World atheriniforms, is strongly associated with maleness and probably important for testicular development in this Old World atheriniform. Thus, amhy is a candidate sex determination gene in cobaltcap silverside and it will be key to scrutinize the mechanism of sex determination in this species. Copyright © 2017 Bej et al.

The evolution of environmental and genetic sex determination in fluctuating environments.

PubMed

Van Dooren, Tom J M; Leimar, Olof

2003-12-01

Twenty years ago, Bulmer and Bull suggested that disruptive selection, produced by environmental fluctuations, can result in an evolutionary transition from environmental sex determination (ESD) to genetic sex determination (GSD). We investigated the feasibility of such a process, using mutation-limited adaptive dynamics and individual-based computer simulations. Our model describes the evolution of a reaction norm for sex determination in a metapopulation setting with partial migration and variation in an environmental variable both within and between local patches. The reaction norm represents the probability of becoming a female as a function of environmental state and was modeled as a sigmoid function with two parameters, one giving the location (i.e., the value of the environmental variable for which an individual has equal chance of becoming either sex) and the other giving the slope of the reaction norm for that environment. The slope can be interpreted as being set by the level of developmental noise in morph determination, with less noise giving a steeper slope and a more switchlike reaction norm. We found convergence stable reaction norms with intermediate to large amounts of developmental noise for conditions characterized by low migration rates, small differential competitive advantages between the sexes over environments, and little variation between individual environments within patches compared to variation between patches. We also considered reaction norms with the slope parameter constrained to a high value, corresponding to little developmental noise. For these we found evolutionary branching in the location parameter and a transition from ESD toward GSD, analogous to the original analysis by Bulmer and Bull. Further evolutionary change, including dominance evolution, produced a polymorphism acting as a GSD system with heterogamety. Our results point to the role of developmental noise in the evolution of sex determination.

Mapping the sex determination locus in the hāpuku (Polyprion oxygeneios) using ddRAD sequencing.

PubMed

Brown, Jeremy K; Taggart, John B; Bekaert, Michaël; Wehner, Stefanie; Palaiokostas, Christos; Setiawan, Alvin N; Symonds, Jane E; Penman, David J

2016-06-10

Hāpuku (Polyprion oxygeneios) is a member of the wreckfish family (Polyprionidae) and is highly regarded as a food fish. Although adults grow relatively slowly, juveniles exhibit low feed conversion ratios and can reach market size in 1-2 years, making P. oxygeneios a strong candidate for aquaculture. However, they can take over 5 years to reach sexual maturity in captivity and are not externally sexually dimorphic, complicating many aspects of broodstock management. Understanding the sex determination system of P. oxygeneios and developing accurate assays to assign genetic sex will contribute significantly towards its full-scale commercialisation. DNA from parents and sexed offspring (n = 57) from a single family of captive bred P. oxygeneios was used as a template for double digestion Restriction-site Associated DNA (ddRAD) sequencing. Two libraries were constructed using SbfI - SphI and SbfI - NcoI restriction enzyme combinations, respectively. Two runs on an Illumina MiSeq platform generated 70,266,464 raw reads, identifying 19,669 RAD loci. A combined sex linkage map (1367 cM) was constructed based on 1575 Single Nucleotide Polymorphism (SNP) markers that resolved into 35 linkage groups. Sex-specific linkage maps were of similar size (1132 and 1168 cM for male and female maps respectively). A single major sex-determining locus, found to be heterogametic in males, was mapped to linkage group 14. Several markers were found to be in strong linkage disequilibrium with the sex-determining locus. Allele-specific PCR assays were developed for two of these markers, SphI6331 and SphI8298, and demonstrated to accurately differentiate sex in progeny within the same pedigree. Comparative genomic analyses indicated that many of the linkage groups within the P. oxygeneios map share a relatively high degree of homology with those published for the European seabass (Dicentrarchus labrax). P. oxygeneios has an XX/XY sex determination system. Evaluation of allele-specific PCR assays, based on the two SNP markers most closely associated with phenotypic sex, indicates that a simple molecular assay for sexing P. oxygeneios should be readily attainable. The high degree of synteny observed with D. labrax should aid further molecular genetic study and exploitation of hāpuku as a food fish.

A Large Pseudoautosomal Region on the Sex Chromosomes of the Frog Silurana tropicalis

PubMed Central

Bewick, Adam J.; Chain, Frédéric J.J.; Zimmerman, Lyle B.; Sesay, Abdul; Gilchrist, Michael J.; Owens, Nick D.L.; Seifertova, Eva; Krylov, Vladimir; Macha, Jaroslav; Tlapakova, Tereza; Kubickova, Svatava; Cernohorska, Halina; Zarsky, Vojtech; Evans, Ben J.

2013-01-01

Sex chromosome divergence has been documented across phylogenetically diverse species, with amphibians typically having cytologically nondiverged (“homomorphic”) sex chromosomes. With an aim of further characterizing sex chromosome divergence of an amphibian, we used “RAD-tags” and Sanger sequencing to examine sex specificity and heterozygosity in the Western clawed frog Silurana tropicalis (also known as Xenopus tropicalis). Our findings based on approximately 20 million genotype calls and approximately 200 polymerase chain reaction-amplified regions across multiple male and female genomes failed to identify a substantially sized genomic region with genotypic hallmarks of sex chromosome divergence, including in regions known to be tightly linked to the sex-determining region. We also found that expression and molecular evolution of genes linked to the sex-determining region did not differ substantially from genes in other parts of the genome. This suggests that the pseudoautosomal region, where recombination occurs, comprises a large portion of the sex chromosomes of S. tropicalis. These results may in part explain why African clawed frogs have such a high incidence of polyploidization, shed light on why amphibians have a high rate of sex chromosome turnover, and raise questions about why homomorphic sex chromosomes are so prevalent in amphibians. PMID:23666865

Different autosomes evolved into sex chromosomes in the sister genera of Salix and Populus

PubMed Central

Hou, Jing; Ye, Ning; Zhang, Defang; Chen, Yingnan; Fang, Lecheng; Dai, Xiaogang; Yin, Tongming

2015-01-01

Willows (Salix) and poplars (Populus) are dioecious plants in Salicaceae family. Sex chromosome in poplar genome was consistently reported to be associated with chromosome XIX. In contrast to poplar, this study revealed that chromosome XV was sex chromosome in willow. Previous studies revealed that both ZZ/ZW and XX/XY sex-determining systems could be present in some species of Populus. In this study, sex of S. suchowensis was found to be determined by the ZW system in which the female was the heterogametic gender. Gene syntenic and collinear comparisons revealed macrosynteny between sex chromosomes and the corresponding autosomes between these two lineages. By contrast, no syntenic segments were found to be shared between poplar's and willow's sex chromosomes. Syntenic analysis also revealed substantial chromosome rearrangements between willow's alternate sex chromatids. Since willow and poplar originate from a common ancestor, we proposed that evolution of autosomes into sex chromosomes in these two lineages occurred after their divergence. Results of this study indicate that sex chromosomes in Salicaceae are still at the early stage of evolutionary divergence. Additionally, this study provided valuable information for better understanding the genetics and evolution of sex chromosome in dioecious plants. PMID:25766834

Haploid, diploid, and triploid--discrimination ability against polyploid mating partner in the parasitic wasp, Bracon brevicornis (Hymenoptera: Braconidae).

PubMed

Thiel, Andra; Weeda, Anne C

2014-01-01

Because the quality of mating partners varies, females of several taxa have evolved the ability to discriminate against low-quality mates. Although males in the Hymenoptera are usually haploid, diploid males may occur in species with complementary sex determination. Diploid males are almost always sterile in most of the species studied so far. They are thus of very low quality as mating partners, especially when females mate only once in life. We hypothesize that hymenopteran females might have evolved the ability to discriminate against infertile diploid males and avoid mating with them. To test this hypothesis, we studied diploid male fitness in the parasitoid wasp Bracon brevicornis Wesmael (Hymenoptera: Braconidae) by measuring survival rate and fertility and then estimated their chances of actually mating with a female. Flow cytometry was used to determine the ploidy level of wasps. The fitness costs of mating a diploid male are indeed high in this species: only 15% were able to sire daughters, of which 97% were triploid and hardly able to produce viable offspring. In contrast to the hypothesis of unsuitable mate discrimination though, no evidence was found for increased rejection of diploid males by females. Male discrimination against an unsuitable partner did also not occur: triploid females elicited the same intensity of courtship behavior in males than did diploid ones. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

Thyroid hormone modulates offspring sex ratio in a turtle with temperature-dependent sex determination

PubMed Central

Li, Teng; Mu, Yi; McGlashan, Jessica K.; Georges, Arthur

2016-01-01

The adaptive significance of temperature-dependent sex determination (TSD) has attracted a great deal of research, but the underlying mechanisms by which temperature determines the sex of a developing embryo remain poorly understood. Here, we manipulated the level of a thyroid hormone (TH), triiodothyronine (T3), during embryonic development (by adding excess T3 to the eggs of the red-eared slider turtle Trachemys scripta, a reptile with TSD), to test two competing hypotheses on the proximate basis for TSD: the developmental rate hypothesis versus the hormone hypothesis. Exogenous TH accelerated embryonic heart rate (and hence metabolic rate), developmental rate, and rates of early post-hatching growth. More importantly, hyperthyroid conditions depressed expression of Cyp19a1 (the gene encoding for aromatase) and levels of oestradiol, and induced more male offspring. This result is contrary to the direction of sex-ratio shift predicted by the developmental rate hypothesis, but consistent with that predicted by the hormone hypothesis. Our results suggest an important role for THs in regulating sex steroid hormones, and therefore, in affecting gonadal sex differentiation in TSD reptiles. Our study has implications for the conservation of TSD reptiles in the context of global change because environmental contaminants may disrupt the activity of THs, and thereby affect offspring sex in TSD reptiles. PMID:27798296

Plant contributions to our understanding of sex chromosome evolution.

PubMed

Charlesworth, Deborah

2015-10-01

A minority of angiosperms have male and female flowers separated in distinct individuals (dioecy), and most dioecious plants do not have cytologically different (heteromorphic) sex chromosomes. Plants nevertheless have several advantages for the study of sex chromosome evolution, as genetic sex determination has evolved repeatedly and is often absent in close relatives. I review sex-determining regions in non-model plant species, which may help us to understand when and how (and, potentially, test hypotheses about why) recombination suppression evolves within young sex chromosomes. I emphasize high-throughput sequencing approaches that are increasingly being applied to plants to test for non-recombining regions. These data are particularly illuminating when combined with sequence data that allow phylogenetic analyses, and estimates of when these regions evolved. Together with comparative genetic mapping, this has revealed that sex-determining loci and sex-linked regions evolved independently in many plant lineages, sometimes in closely related dioecious species, and often within the past few million years. In reviewing recent progress, I suggest areas for future work, such as the use of phylogenies to allow the informed choice of outgroup species suitable for inferring the directions of changes, including testing whether Y chromosome-like regions are undergoing genetic degeneration, a predicted consequence of losing recombination. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Di (2-ethylhexyl) phthalate exposure during pregnancy disturbs temporal sex determination regulation in mice offspring.

PubMed

Wang, Yongan; Liu, Wei; Yang, Qing; Yu, Mingxi; Zhang, Zhou

2015-10-02

Animal researches and clinical studies have supported the relevance between phthalates exposure and testicular dysgenesis syndrome (TDS). These disorders may comprise common origin in fetal life, especially during sex determination and differentiation, where the mechanism remains unclear. The present study evaluated the disturbances in gene regulatory networks of sex determination in fetal mouse by in utero Di (2-ethylhexyl) phthalate (DEHP) exposure. Temporal expression of key sex determination genes were examined during the critical narrow time window, using whole-mount in situ hybridization and quantitative-PCR. DEHP exposure resulted in significant reduction in mRNA of Sry during sex determination from gestation day (GD) 11.0 to 11.5 in male fetal mice, and the increasing of Sry expression to threshold level on GD 11.5 was delayed. Meanwhile, Gadd45g and Gata4, the upstream genes of Sry, and downstream gene Sox9 were also significantly downregulated in expression. In fetal females, the expression of Wnt4 and beta-catenin were up-regulated by DEHP exposure. Taken together, the results suggest that the potential mechanism of gonadal development disorder by DEHP may origin from repression of important male sex determination signaling pathway, involving Gadd45g → Gata4 → Sry → Sox9. The results would promote a better understanding of the association between phthalate esters (PAEs) exposure and the reductive disorder. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Ethylene responsive factor ERF110 mediates ethylene-regulated transcription of a sex determination-related orthologous gene in two Cucumis species.

PubMed

Tao, Qianyi; Niu, Huanhuan; Wang, Zhongyuan; Zhang, Wenhui; Wang, Hu; Wang, Shenhao; Zhang, Xian; Li, Zheng

2018-05-25

In plants, unisexual flowers derived from developmental sex determination form separate stamens and pistils that facilitate cross pollination. In cucumber and melon, ethylene plays a key role in sex determination. Six sex determination-related genes have been identified in ethylene biosynthesis in these Cucumis species. The interactions among these genes are thought to involve ethylene signaling; however, the underlying mechanism of regulation remains unknown. In this study, hormone treatment and qPCR assays were used to confirm expression of these sex determination-related genes in cucumber and melon is ethylene sensitive. RNA-Seq analysis subsequently helped identify the ethylene responsive factor (ERF) gene, CsERF110, related to ethylene signaling and sex determination. CsERF110 and its melon ortholog, CmERF110, shared a conserved AP2/ERF domain and showed ethylene-sensitive expression. Yeast one-hybrid and ChIP-PCR assays further indicated that CsERF110 bound to at least two sites in the promoter fragment of CsACS11, while transient transformation analysis showed that CsERF110 and CmERF110 enhance CsACS11 and CmACS11 promoter activity, respectively. Taken together, these findings suggest that CsERF110 and CmERF110 respond to ethylene signaling, mediating ethylene-regulated transcription of CsACS11 and CmACS11 in cucumber and melon, respectively. Furthermore, the mechanism involved in its regulation is thought to be conserved in these two Cucumis species.

Plasticity of gene-regulatory networks controlling sex determination: of masters, slaves, usual suspects, newcomers, and usurpators.

PubMed

Herpin, Amaury; Schartl, Manfred

2015-10-01

Sexual dimorphism is one of the most pervasive and diverse features of animal morphology, physiology, and behavior. Despite the generality of the phenomenon itself, the mechanisms controlling how sex is determined differ considerably among various organismic groups, have evolved repeatedly and independently, and the underlying molecular pathways can change quickly during evolution. Even within closely related groups of organisms for which the development of gonads on the morphological, histological, and cell biological level is undistinguishable, the molecular control and the regulation of the factors involved in sex determination and gonad differentiation can be substantially different. The biological meaning of the high molecular plasticity of an otherwise common developmental program is unknown. While comparative studies suggest that the downstream effectors of sex-determining pathways tend to be more stable than the triggering mechanisms at the top, it is still unclear how conserved the downstream networks are and how all components work together. After many years of stasis, when the molecular basis of sex determination was amenable only in the few classical model organisms (fly, worm, mouse), recently, sex-determining genes from several animal species have been identified and new studies have elucidated some novel regulatory interactions and biological functions of the downstream network, particularly in vertebrates. These data have considerably changed our classical perception of a simple linear developmental cascade that makes the decision for the embryo to develop as male or female, and how it evolves. © 2015 The Authors.

Systematic, genome-wide, sex-specific linkage of cardiovascular traits in French Canadians.

PubMed

Seda, Ondrej; Tremblay, Johanne; Gaudet, Daniel; Brunelle, Pierre-Luc; Gurau, Alexandru; Merlo, Ettore; Pilote, Louise; Orlov, Sergei N; Boulva, Francis; Petrovich, Milan; Kotchen, Theodore A; Cowley, Allen W; Hamet, Pavel

2008-04-01

The sexual dimorphism of cardiovascular traits, as well as susceptibility to a variety of related diseases, has long been recognized, yet their sex-specific genomic determinants are largely unknown. We systematically assessed the sex-specific heritability and linkage of 539 hemodynamic, metabolic, anthropometric, and humoral traits in 120 French-Canadian families from the Saguenay-Lac-St-Jean region of Quebec, Canada. We performed multipoint linkage analysis using microsatellite markers followed by peak-wide linkage scan based on Affymetrix Human Mapping 50K Array Xba240 single nucleotide polymorphism genotypes in 3 settings, including the entire sample and then separately in men and women. Nearly one half of the traits were age and sex independent, one quarter were both age and sex dependent, and one eighth were exclusively age or sex dependent. Sex-specific phenotypes are most frequent in heart rate and blood pressure categories, whereas sex- and age-independent determinants are predominant among humoral and biochemical parameters. Twenty sex-specific loci passing multiple testing criteria were corroborated by 2-point single nucleotide polymorphism linkage. Several resting systolic blood pressure measurements showed significant genotype-by-sex interaction, eg, male-specific locus at chromosome 12 (male-female logarithm of odds difference: 4.16; interaction P=0.0002), which was undetectable in the entire population, even after adjustment for sex. Detailed interrogation of this locus revealed a 220-kb block overlapping parts of TAO-kinase 3 and SUDS3 genes. In summary, a large number of complex cardiovascular traits display significant sexual dimorphism, for which we have demonstrated genomic determinants at the haplotype level. Many of these would have been missed in a traditional, sex-adjusted setting.

Flower development and sex specification in wild grapevine.

PubMed

Ramos, Miguel Jesus Nunes; Coito, João Lucas; Silva, Helena Gomes; Cunha, Jorge; Costa, Maria Manuela Ribeiro; Rocheta, Margarida

2014-12-12

Wild plants of Vitis closely related to the cultivated grapevine (V. v. vinifera) are believed to have been first domesticated 10,000 years BC around the Caspian Sea. V. v. vinifera is hermaphrodite whereas V. v. sylvestris is a dioecious species. Male flowers show a reduced pistil without style or stigma and female flowers present reflexed stamens with infertile pollen. V. vinifera produce perfect flowers with all functional structures. The mechanism for flower sex determination and specification in grapevine is still unknown. To understand which genes are involved during the establishment of male, female and complete flowers, we analysed and compared the transcription profiles of four developmental stages of the three genders. We showed that sex determination is a late event during flower development and that the expression of genes from the ABCDE model is not directly correlated with the establishment of sexual dimorphism. We propose a temporal comprehensive model in which two mutations in two linked genes could be players in sex determination and indirectly establish the Vitis domestication process. Additionally, we also found clusters of genes differentially expressed between genders and between developmental stages that suggest a role involved in sex differentiation. Also, the detection of differentially transcribed regions that extended existing gene models (intergenic regions) between sexes suggests that they may account for some of the variation between the subspecies. There is no evidence of differences of expression levels in genes from the ABCDE model that could explain the shift from hermaphroditism to dioecy. We propose that sex specification occurs after floral organ identity has been established and therefore, sex determination genes might be having an effect downstream of the ABCDE model genes.For the first time a full transcriptomic analysis was performed in different flower developmental stages in the same individual. Our experimental approach enabled us to create a comprehensive catalogue of transcribed genes across developmental stages and genders that will contribute for future work in sex determination in seed plants.

A 11.7-kb deletion triggers intersexuality and polledness in goats.

PubMed

Pailhoux, E; Vigier, B; Chaffaux, S; Servel, N; Taourit, S; Furet, J P; Fellous, M; Grosclaude, F; Cribiu, E P; Cotinot, C; Vaiman, D

2001-12-01

Mammalian sex determination is governed by the presence of the sex determining region Y gene (SRY) on the Y chromosome. Familial cases of SRY-negative XX sex reversal are rare in humans, often hampering the discovery of new sex-determining genes. The mouse model is also insufficient to correctly apprehend the sex-determination cascade, as the human pathway is much more sensitive to gene dosage. Other species might therefore be considered in this respect. In goats, the polled intersex syndrome (PIS) mutation associates polledness and intersexuality. The sex reversal affects exclusively the XX individuals in a recessive manner, whereas the absence of horns is dominant in both sexes. The syndrome is caused by an autosomal gene located at chromosome band 1q43 (ref. 9), shown to be homologous to human chromosome band 3q23 (ref. 10). Through a positional cloning approach, we demonstrate that the mutation underlying PIS is the deletion of a critical 11.7-kb DNA element containing mainly repetitive sequences. This deletion affects the transcription of at least two genes: PISRT1, encoding a 1.5-kb mRNA devoid of open reading frame (ORF), and FOXL2, recently shown to be responsible for blepharophimosis ptosis epicanthus inversus syndrome (BPES) in humans. These two genes are located 20 and 200 kb telomeric from the deletion, respectively.

Assigning sex and reproductive stage to adult Lake Sturgeon using ultrasonography and common morphological measurements

USGS Publications Warehouse

Chiotti, Justin A.; Boase, James C.; Hondorp, Darryl W.; Briggs, Andrew S.

2016-01-01

Sex determination of fish species is difficult to assess when sexual dimorphism and gametes are not apparent. For threatened and endangered fish species, noninvasive techniques are needed when determining sex to minimize stress and the potential for mortality. We evaluated the use of a portable ultrasound unit to determine sex of Lake Sturgeon Acipenser fulvescens in the field. Ultrasound images were collected from 9 yellow-egg (F2, F3), 32 black-egg (F4, F5), and 107 fully developed male (M2) Lake Sturgeon. Two readers accurately assigned sex to 88–96% of fish, but accuracy varied in relation to maturity stage. Black-egg females and fully developed males were correctly identified for 89–100% of the fish sampled, while these two readers identified yellow-egg females only 33% and 67% of the time. Time spent collecting images ranged between 2 and 3 min once the user was comfortable with operating procedures. Discriminant analysis revealed the total length : girth ratio was a strong predictor of sex and maturity, correctly classifying 81% of black-egg females and 97% of the fully developed males. However, yellow-egg females were incorrectly classified on all occasions. This study shows the utility of using ultrasonography and a total length : girth ratio for sex determination of Lake Sturgeon in later reproductive stages around the spawning season.

Gonadal Transcriptome Analysis of Male and Female Olive Flounder (Paralichthys olivaceus)

PubMed Central

Fan, Zhaofei; You, Feng; Wang, Lijuan; Weng, Shenda; Wu, Zhihao; Hu, Jinwei; Zou, Yuxia; Tan, Xungang; Zhang, Peijun

2014-01-01

Olive flounder (Paralichthys olivaceus) is an important commercially cultured marine flatfish in China, Korea, and Japan, of which female grows faster than male. In order to explore the molecular mechanism of flounder sex determination and development, we used RNA-seq technology to investigate transcriptomes of flounder gonads. This produced 22,253,217 and 19,777,841 qualified reads from ovary and testes, which were jointly assembled into 97,233 contigs. Among them, 23,223 contigs were mapped to known genes, of which 2,193 were predicted to be differentially expressed in ovary and 887 in testes. According to annotation information, several sex-related biological pathways including ovarian steroidogenesis and estrogen signaling pathways were firstly found in flounder. The dimorphic expression of overall sex-related genes provides further insights into sex determination and gonadal development. Our study also provides an archive for further studies of molecular mechanism of fish sex determination. PMID:25121093

Genetic basis and biotechnological manipulation of sexual dimorphism and sex determination in fish.

PubMed

Mei, Jie; Gui, Jian-Fang

2015-02-01

Aquaculture has made an enormous contribution to the world food production, especially to the sustainable supply of animal proteins. The utility of diverse reproduction strategies in fish, such as the exploiting use of unisexual gynogenesis, has created a typical case of fish genetic breeding. A number of fish species show substantial sexual dimorphism that is closely linked to multiple economic traits including growth rate and body size, and the efficient development of sex-linked genetic markers and sex control biotechnologies has provided significant approaches to increase the production and value for commercial purposes. Along with the rapid development of genomics and molecular genetic techniques, the genetic basis of sexual dimorphism has been gradually deciphered, and great progress has been made in the mechanisms of fish sex determination and identification of sex-determining genes. This review summarizes the progress to provide some directive and objective thinking for further research in this field.

Molecular method for determining sex of walruses

USGS Publications Warehouse

Fischbach, Anthony S.; Jay, C.V.; Jackson, J.V.; Andersen, L.W.; Sage, G.K.; Talbot, S.L.

2008-01-01

We evaluated the ability of a set of published trans-species molecular sexing primers and a set of walrus-specific primers, which we developed, to accurately identify sex of 235 Pacific walruses (Odobenus rosmarus divergens). The trans-species primers were developed for mammals and targeted the X- and Y-gametologs of the zinc finger protein genes (ZFX, ZFY). We extended this method by using these primers to obtain sequence from Pacific and Atlantic walrus (0. r. rosmarus) ZFX and ZFY genes to develop new walrus-specific primers, which yield polymerase chain reaction products of distinct lengths (327 and 288 base pairs from the X- and Y-chromosome, respectively), allowing them to be used for sex determination. Both methods yielded a determination of sex in all but 1-2% of samples with an accuracy of 99.6-100%. Our walrus-specific primers offer the advantage of small fragment size and facile application to automated electrophoresis and visualization.

Optical remote sensing of asteroid surfaces from spacecraft

NASA Technical Reports Server (NTRS)

Mccord, T. B.

1978-01-01

Reflectance spectroscopy and multispectral mapping are the techniques likely to be most useful for determining asteroid surfaces. Several other techniques should be considered for providing complementary information.

Determinants of unprotected casual heterosexual sex in Ghana.

PubMed

Kumi-Kyereme, Akwasi; Tuoyire, Derek A; Darteh, Eugene K M

2014-05-01

Casual heterosexual sex remains a significant contributor to HIV transmissions in Ghana. The study used data from the 2008 Ghana Demographic and Health Survey (GDHS) to assess the socio-demographic, economic and spatial factors influencing unprotected casual heterosexual sex among men and women. The results of the binary logistic regression models revealed that women aged 35-44 had significantly higher odds of engaging in unprotected casual heterosexual sex than those aged 15-24, unlike the men. There were significantly lower odds of unprotected casual heterosexual sex for women and men with exposure to print media compared with those without exposure. Compared with men residing in the Western Region, unprotected casual heterosexual sex was significantly less likely among those in the Upper East Region. There is the need for behavioural change campaigns in Ghana that take into consideration the multiplicity of factors that determine unprotected casual heterosexual sex.

Nucleotide Sequence Analysis of RNA Synthesized from Rabbit Globin Complementary DNA

PubMed Central

Poon, Raymond; Paddock, Gary V.; Heindell, Howard; Whitcome, Philip; Salser, Winston; Kacian, Dan; Bank, Arthur; Gambino, Roberto; Ramirez, Francesco

1974-01-01

Rabbit globin complementary DNA made with RNA-dependent DNA polymerase (reverse transcriptase) was used as template for in vitro synthesis of 32P-labeled RNA. The sequences of the nucleotides in most of the fragments resulting from combined ribonuclease T1 and alkaline phosphatase digestion have been determined. Several fragments were long enough to fit uniquely with the α or β globin amino-acid sequences. These data demonstrate that the cDNA was copied from globin mRNA and contained no detectable contaminants. Images PMID:4139714

Noninvasive Evaluation of Special Alloys for Prostheses Using Complementary Methods

NASA Astrophysics Data System (ADS)

Savin, A.; Vizureanu, P.; Prevorovsky, Z.; Chlada, M.; Krofta, J.; Baltatu, M. S.; Istrate, B.; Steigmann, R.

2018-06-01

Ti-Mo-Si alloys have gained the attention of biomedical industry due to specific strength and corrosion resistance and the best biocompatibility among metallic materials used in medical prostheses. In order to characterize the material, the experimental determination of elastic matrix, mechanical wear and the probability of appearance and propagation of thin cracks are imposed. Thus, resonant ultrasound spectroscopy and acoustic emission as non-invasive methods and complementary methods as SEM, EDX are involved, to choose the best concentration of elements with the aim of mechanical properties improvement.

Comparative transcriptome analysis reveals differentially expressed genes associated with sex expression in garden asparagus (Asparagus officinalis).

PubMed

Li, Shu-Fen; Zhang, Guo-Jun; Zhang, Xue-Jin; Yuan, Jin-Hong; Deng, Chuan-Liang; Gao, Wu-Jun

2017-08-22

Garden asparagus (Asparagus officinalis) is a highly valuable vegetable crop of commercial and nutritional interest. It is also commonly used to investigate the mechanisms of sex determination and differentiation in plants. However, the sex expression mechanisms in asparagus remain poorly understood. De novo transcriptome sequencing via Illumina paired-end sequencing revealed more than 26 billion bases of high-quality sequence data from male and female asparagus flower buds. A total of 72,626 unigenes with an average length of 979 bp were assembled. In comparative transcriptome analysis, 4876 differentially expressed genes (DEGs) were identified in the possible sex-determining stage of female and male/supermale flower buds. Of these DEGs, 433, including 285 male/supermale-biased and 149 female-biased genes, were annotated as flower related. Of the male/supermale-biased flower-related genes, 102 were probably involved in anther development. In addition, 43 DEGs implicated in hormone response and biosynthesis putatively associated with sex expression and reproduction were discovered. Moreover, 128 transcription factor (TF)-related genes belonging to various families were found to be differentially expressed, and this finding implied the essential roles of TF in sex determination or differentiation in asparagus. Correlation analysis indicated that miRNA-DEG pairs were also implicated in asparagus sexual development. Our study identified a large number of DEGs involved in the sex expression and reproduction of asparagus, including known genes participating in plant reproduction, plant hormone signaling, TF encoding, and genes with unclear functions. We also found that miRNAs might be involved in the sex differentiation process. Our study could provide a valuable basis for further investigations on the regulatory networks of sex determination and differentiation in asparagus and facilitate further genetic and genomic studies on this dioecious species.

Climate change and temperature-dependent sex determination: can individual plasticity in nesting phenology prevent extreme sex ratios?

PubMed

Schwanz, Lisa E; Janzen, Fredric J

2008-01-01

Under temperature-dependent sex determination (TSD), temperatures experienced by embryos during development determine the sex of the offspring. Consequently, populations of organisms with TSD have the potential to be strongly impacted by climatic warming that could bias offspring sex ratio, a fundamental demographic parameter involved in population dynamics. Moreover, many taxa with TSD are imperiled, so research on this phenomenon, particularly long-term field study, has assumed great urgency. Recently, turtles with TSD have joined the diverse list of taxa that have demonstrated population-level changes in breeding phenology in response to recent climate change. This raises the possibility that any adverse impacts of climate change on populations may be alleviated by individual plasticity in nesting phenology. Here, we examine data from a long-term study on a population of painted turtles (Chrysemys picta) to determine whether changes in phenology are due to individual plasticity and whether individual plasticity in the timing of nesting has the capacity to offset the sex ratio effects of a rise in climatic temperature. We find that individual females show plasticity in the date of first nesting each year, and that this plasticity depends on the climate from the previous winter. First nesting date is not repeatable within individuals, suggesting that it would not respond to selection. Sex ratios of hatchlings within a nest declined nonsignificantly over the nesting season. However, small increases in summer temperature had a much stronger effect on nest sex ratios than did laying nests earlier in the season. For this and other reasons, it seems unlikely that individual plasticity in the timing of nesting will offset the effects of climate change on sex ratios in this population, and we hypothesize that this conclusion applies to other populations with TSD.

Transitions in Sexuality: Recapitulation of an Ancestral Tri- and Tetrapolar Mating System in Cryptococcus neoformans▿ †

PubMed Central

Hsueh, Yen-Ping; Fraser, James A.; Heitman, Joseph

2008-01-01

Sex is orchestrated by the mating-type locus (MAT) in fungi and by sex chromosomes in plants and animals. In fungi, two patterns of sexuality occur: bipolar with a single, typically biallelic sex determinant that promotes inbreeding, and tetrapolar with two unlinked, often multiallelic sex determinants that restrict inbreeding. Multiallelism in either bipolar or tetrapolar mating systems promotes outcrossing. Cryptococcus neoformans is a pathogenic bipolar yeast with two unusually large MAT alleles (a/α) spanning >100 kb, ∼100-fold larger than many other fungal MAT loci. Based on comparative genomic analysis, this unusual MAT locus is hypothesized to have evolved from an ancestral tetrapolar system. In this model, the unlinked homeodomain (HD) transcription factor and pheromone/receptor tetrapolar loci acquired additional sex-related genes and then fused via chromosomal translocation, forming an intermediate transitional mating system (which we term tripolar), which then underwent recombination and gene conversion to fashion the extant bipolar MAT alleles. To experimentally validate this model, C. neoformans was engineered to have a tetrapolar mating system by relocating the MAT SXI1α and SXI2a HD genes to an unlinked genomic locale. Genetic and molecular analyses revealed that this modified organism could complete a tetrapolar sexual cycle. Analysis of progeny generated from bipolar, tripolar, and tetrapolar crosses provides direct experimental evidence that the tripolar state confers decreased fertility and therefore may represent an unstable evolutionary intermediate. These findings illustrate how transitions between outcrossing and inbreeding preference occur by involving sex determinant linkage and collapse from multiallelic to biallelic sex determination, providing insights into both fungal sex evolution and early steps in sex chromosome evolution. PMID:18723606

Validation of endoscopy for determination of maturity in small salmonids and sex of mature individuals

Treesearch

Erica A. Swenson; Amanda E. Rosenberger; Philip J. Howell

2007-01-01

Fish maturity status, sex ratio, and age and size at first maturity are important parameters in population assessments and life history studies. In most empirical studies of these variables, fish are sacrificed and dissected to obtain data. However, maturity status and the sex of mature individuals can be determined by inserting an endoscope through a small incision in...

A Tandem Duplicate of Anti-Müllerian Hormone with a Missense SNP on the Y Chromosome Is Essential for Male Sex Determination in Nile Tilapia, Oreochromis niloticus

PubMed Central

Li, Minghui; Sun, Yunlv; Zhao, Jiue; Shi, Hongjuan; Zeng, Sheng; Ye, Kai; Jiang, Dongneng; Zhou, Linyan; Sun, Lina; Tao, Wenjing; Nagahama, Yoshitaka; Kocher, Thomas D.; Wang, Deshou

2015-01-01

Variation in the TGF-β signaling pathway is emerging as an important mechanism by which gonadal sex determination is controlled in teleosts. Here we show that amhy, a Y-specific duplicate of the anti-Müllerian hormone (amh) gene, induces male sex determination in Nile tilapia. amhy is a tandem duplicate located immediately downstream of amhΔ-y on the Y chromosome. The coding sequence of amhy was identical to the X-linked amh (amh) except a missense SNP (C/T) which changes an amino acid (Ser/Leu92) in the N-terminal region. amhy lacks 5608 bp of promoter sequence that is found in the X-linked amh homolog. The amhΔ-y contains several insertions and deletions in the promoter region, and even a 5 bp insertion in exonVI that results in a premature stop codon and thus a truncated protein product lacking the TGF-β binding domain. Both amhy and amhΔ-y expression is restricted to XY gonads from 5 days after hatching (dah) onwards. CRISPR/Cas9 knockout of amhy in XY fish resulted in male to female sex reversal, while mutation of amhΔ-y alone could not. In contrast, overexpression of Amhy in XX fish, using a fosmid transgene that carries the amhy/amhΔ-y haplotype or a vector containing amhy ORF under the control of CMV promoter, resulted in female to male sex reversal, while overexpression of AmhΔ-y alone in XX fish could not. Knockout of the anti-Müllerian hormone receptor type II (amhrII) in XY fish also resulted in 100% complete male to female sex reversal. Taken together, these results strongly suggest that the duplicated amhy with a missense SNP is the candidate sex determining gene and amhy/amhrII signal is essential for male sex determination in Nile tilapia. These findings highlight the conserved roles of TGF-β signaling pathway in fish sex determination. PMID:26588702

A microRNA family exerts maternal control on sex determination in C. elegans

PubMed Central

McJunkin, Katherine; Ambros, Victor

2017-01-01

Gene expression in early animal embryogenesis is in large part controlled post-transcriptionally. Maternally contributed microRNAs may therefore play important roles in early development. We elucidated a major biological role of the nematode mir-35 family of maternally contributed essential microRNAs. We show that this microRNA family regulates the sex determination pathway at multiple levels, acting both upstream of and downstream from her-1 to prevent aberrantly activated male developmental programs in hermaphrodite embryos. Both of the predicted target genes that act downstream from the mir-35 family in this process, suppressor-26 (sup-26) and NHL (NCL-1, HT2A, and LIN-41 repeat) domain-containing-2 (nhl-2), encode RNA-binding proteins, thus delineating a previously unknown post-transcriptional regulatory subnetwork within the well-studied sex determination pathway of Caenorhabditis elegans. Repression of nhl-2 by the mir-35 family is required for not only proper sex determination but also viability, showing that a single microRNA target site can be essential. Since sex determination in C. elegans requires zygotic gene expression to read the sex chromosome karyotype, early embryos must remain gender-naïve; our findings show that the mir-35 family microRNAs act in the early embryo to function as a developmental timer that preserves naïveté and prevents premature deleterious developmental decisions. PMID:28279983

Incubation history prior to the canonical thermosensitive period determines sex in the American alligator.

PubMed

McCoy, Jessica A; Parrott, Benjamin B; Rainwater, Thomas R; Wilkinson, Phillip M; Guillette, Louis J

2015-10-01

Despite the widespread occurrence of environmental sex determination (ESD) among vertebrates, our knowledge of the temporal dynamics by which environmental factors act on this process remains limited. In many reptiles, incubation temperature determines sex during a discrete developmental window just prior to and coincident with the differentiation of the gonads. Yet, there is substantial variation in sex ratios among different clutches of eggs incubated at identical temperatures during this period. Here, we test the hypothesis that temperatures experienced prior to the reported thermosensitive period for alligators (Alligator mississippiensis) can impact how the sex determination system responds to thermal cues later in development. Temperature shift experiments on eggs collected from the field within 24  h of oviposition were employed to decouple various maternal influences from thermal effects, and results demonstrate a previously undefined window of thermosensitivity occurring by stage 15 of embryonic development, six stages earlier than previously reported. We also examine the intrasexual expression of several male- and female-biased genes and show that while male-biased genes display no intrasexual differences, ovarian CYP19A1 (aromatase) transcript abundance differs by approximately twofold depending on thermal exposures experienced at early stages of embryonic development. These findings expand our understanding of the ESD in the alligator and provide the rationale for reevaluation of the temporal dynamics of sex determination in other crocodilians. © 2015 Society for Reproduction and Fertility.

Multigenerational response to artificial selection for biased clutch sex ratios in Tigriopus californicus populations.

PubMed

Alexander, H J; Richardson, J M L; Anholt, B R

2014-09-01

Polygenic sex determination (PSD) is relatively rare and theoretically evolutionary unstable, yet has been reported across a range of taxa. Evidence for multilocus PSD is provided by (i) large between-family variance in sex ratio, (ii) paternal and maternal effects on family sex ratio and (iii) response to selection for family sex ratio. This study tests the polygenic hypothesis of sex determination in the harpacticoid copepod Tigriopus californicus using the criterion of response to selection. We report the first multigenerational quantitative evidence that clutch sex ratio responds to artificial selection in both directions (selection for male- and female-biased families) and in multiple populations of T. californicus. In the five of six lines that showed a response to selection, realized heritability estimated by multigenerational analysis ranged from 0.24 to 0.58. Divergence of clutch sex ratio between selection lines is rapid, with response to selection detectable within the first four generations of selection. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

The roles of Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes in sex determination and differentiation mechanisms: Ubiquity and diversity across the animal kingdom.

PubMed

Picard, Marion Anne-Lise; Cosseau, Céline; Mouahid, Gabriel; Duval, David; Grunau, Christoph; Toulza, Ève; Allienne, Jean-François; Boissier, Jérôme

2015-07-01

The Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes have been intensively studied because they represent major transcription factors in the pathways governing sex determination and differentiation. These genes have been identified in animal groups ranging from cnidarians to mammals, and some of the genes functionally studied. Here, we propose to analyze (i) the presence/absence of various Dmrt gene groups in the different taxa across the animal kingdom; (ii) the relative expression levels of the Dmrt genes in each sex; (iii) the specific spatial (by organ) and temporal (by developmental stage) variations in gene expression. This review considers non-mammalian animals at all levels of study (i.e. no particular importance is given to animal models), and using all types of sexual strategy (hermaphroditic or gonochoric) and means of sex determination (i.e. genetic or environmental). To conclude this global comparison, we offer an analysis of the DM domains conserved among the different DMRT proteins, and propose a general sex-specific pattern for each member of the Dmrt gene family. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.