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1

Seamless Correction of the Sickle Cell Disease Mutation of the HBB Gene in Human Induced  

E-print Network

Seamless Correction of the Sickle Cell Disease Mutation of the HBB Gene in Human Induced ABSTRACT: Sickle cell disease (SCD) is the most common human genetic disease which is caused by a single effector nucleases; induced pluripotent stem cells; piggyBac transposon; sickle cell disease; gene therapy

Zhao, Huimin

2

Seamless correction of the sickle cell disease mutation of the HBB gene in human induced pluripotent stem cells using TALENs.  

PubMed

Sickle cell disease (SCD) is the most common human genetic disease which is caused by a single mutation of human ?-globin (HBB) gene. The lack of long-term treatment makes the development of reliable cell and gene therapies highly desirable. Disease-specific patient-derived human induced pluripotent stem cells (hiPSCs) have great potential for developing novel cell and gene therapies. With the disease-causing mutations corrected in situ, patient-derived hiPSCs can restore normal cell functions and serve as a renewable autologous cell source for the treatment of genetic disorders. Here we successfully utilized transcription activator-like effector nucleases (TALENs), a recently emerged novel genome editing tool, to correct the SCD mutation in patient-derived hiPSCs. The TALENs we have engineered are highly specific and generate minimal off-target effects. In combination with piggyBac transposon, TALEN-mediated gene targeting leaves no residual ectopic sequences at the site of correction and the corrected hiPSCs retain full pluripotency and a normal karyotype. Our study demonstrates an important first step of using TALENs for the treatment of genetic diseases such as SCD, which represents a significant advance toward hiPSC-based cell and gene therapies. PMID:23928856

Sun, Ning; Zhao, Huimin

2014-05-01

3

Lateral flow dipstick test for genotyping of 15 beta-globin gene (HBB) mutations with naked-eye detection.  

PubMed

For definitive diagnosis of thalassemia carriers and patients, as well as for prenatal diagnosis, genotype analysis is of fundamental importance. We report a dry-reagent, lateral flow dipstick test that enables visual genotyping (detection by naked eye) of 15 mutations common in Mediterranean populations in the beta-globin gene (HBB). The method comprises 3 simple steps: (i) PCR amplification of a single 1896 bp segment of the beta globin gene flanking all 15 mutations; (ii) a multiplex (10-plex and/or 30-plex) primer extension reaction of the unpurified amplification product using allele-specific primers. Biotin is incorporated in the extended product; (iii) a dry-reagent multi-allele (10-plex) dipstick assay for visual detection of the primer extension reaction products within minutes. The total time required for PCR, primer extension reaction and the dipstick assay is ~2 h. The method was evaluated by genotyping 45 DNA samples of known genotypes and 54 blind samples. The results were fully concordant with reference methods. The method is simple, rapid, and cost-effective. Detection by the dipstick assay does not require specialized instrumentation or highly qualified personnel. The proposed method could be a particularly useful tool in laboratories with limited resources and a basis for point-of-care diagnostics especially in combination with PCR amplification from whole blood. PMID:22541824

Papanikos, Frantzeskos; Iliadi, Alexandra; Petropoulou, Margarita; Ioannou, Penelope C; Christopoulos, Theodore K; Kanavakis, Emmanuel; Traeger-Synodinos, Jan

2012-05-21

4

NO ASSOCIATION BETWEEN tHbmass AND POLYMORPHISMS IN THE HBB GENE IN ENDURANCE ATHLETES  

PubMed Central

The aim of this study was to examine the association between tHbmass and HBB gene polymorphisms in athletes of endurance disciplines. Eighty-two well-trained athletes (female n=36, male n=46), aged 19.3 ± 2.7 years, representing cross country skiing (n=37) and middle- and long-distance running (n=45), participated in the study. Genotyping for 2 polymorphisms in the HBB gene (- 551C/T and intron 2, +16 C/G) was performed using restriction fragment length polymorphism analysis. Total haemoglobin mass (tHbmass) was determined by the optimized carbon monoxide rebreathing method. Blood morphology, indices of iron status (ferritin, transferrin receptor and total iron binding capacity) and C reactive protein were also determined. No differences were found in the HBB genotype and allele frequencies between male and female athletes. Regardless of the polymorphisms, no relationships were found between HBB genotypes as well as alleles and relative values of tHbmass, expressed per body mass (g · kg-1 BM), both in female and male athletes. Our results demonstrated that -551 C/T and intron 2, +16 C/G polymorphisms of the HBB gene have no association with total haemoglobin mass in endurance athletes. It cannot be ruled out that several polymorphisms, each with a small but significant contribution, may be responsible for the amount of haemoglobin. PMID:24899775

Malczewska-Lenczowska, J.; Orysiak, J.; Majorczyk, E.; Pokrywka, A.; Kaczmarski, J.; Szygula, Z.

2014-01-01

5

NO ASSOCIATION BETWEEN tHbmass AND POLYMORPHISMS IN THE HBB GENE IN ENDURANCE ATHLETES.  

PubMed

The aim of this study was to examine the association between tHbmass and HBB gene polymorphisms in athletes of endurance disciplines. Eighty-two well-trained athletes (female n=36, male n=46), aged 19.3 ± 2.7 years, representing cross country skiing (n=37) and middle- and long-distance running (n=45), participated in the study. Genotyping for 2 polymorphisms in the HBB gene (- 551C/T and intron 2, +16 C/G) was performed using restriction fragment length polymorphism analysis. Total haemoglobin mass (tHbmass) was determined by the optimized carbon monoxide rebreathing method. Blood morphology, indices of iron status (ferritin, transferrin receptor and total iron binding capacity) and C reactive protein were also determined. No differences were found in the HBB genotype and allele frequencies between male and female athletes. Regardless of the polymorphisms, no relationships were found between HBB genotypes as well as alleles and relative values of tHbmass, expressed per body mass (g · kg(-1) BM), both in female and male athletes. Our results demonstrated that -551 C/T and intron 2, +16 C/G polymorphisms of the HBB gene have no association with total haemoglobin mass in endurance athletes. It cannot be ruled out that several polymorphisms, each with a small but significant contribution, may be responsible for the amount of haemoglobin. PMID:24899775

Malczewska-Lenczowska, J; Orysiak, J; Majorczyk, E; Pokrywka, A; Kaczmarski, J; Szygula, Z; Sitkowski, D

2014-06-01

6

Hereditary gene mutations in Korean patients with isolated erythrocytosis.  

PubMed

Most cases of erythrocytosis occur secondary to chronic tissue hypoxia or as a clonal disease such as polycythemia vera with somatic mutations in the Janus kinase 2 (JAK2) gene. Rarely, erythrocytosis is caused by hereditary gene mutations. This study investigated hereditary gene mutations in 38 unrelated Korean patients with isolated erythrocytosis without (1) JAK2 mutation and (2) secondary causes of erythrocytosis other than smoking history. Direct sequencing analyses were performed on six genes associated with hereditary erythrocytosis [HBB, exon 2 and exon 3 of HBA2, VHL, EGLN1 (previously PHD2), exon 12 of EPAS1 (previously HIF2A), and exons 5-8 of EPOR]. As a result, mutations were detected in five patients (three never smokers and two current smokers) out of 38 patients (13.2 %). The mutations detected in those five patients were EPOR:p.W439*, EPOR:p.G212C, HBB:p.H98Q (or conventionally H97Q, Hb Malmö [? 97(FG4) His > Gln]), HBB:p.V138M (V137M), and EGLN1:p.L279Tfs43*, all in heterozygous state. No patient had mutations in HBA2, VHL, or in EPAS1. This study indicates that workup for hereditary gene mutations is needed for isolated erythrocytosis with or without smoking history. PMID:24482100

Jang, Ja-Hyun; Seo, Ja Young; Jang, Junho; Jung, Chul Won; Lee, Ki-O; Kim, Sun-Hee; Kim, Hee-Jin

2014-06-01

7

A New Hemoglobin Variant: Hb Meylan [?73(E17)Asp???Phe; HBB: c.220G>T; c.221A>T] with a Double Base Mutation at the Same Codon.  

PubMed

Abstract We report a new ?-globin chain variant: Hb Meylan [?73(E17)Asp???Phe; HBB: c.220G>T; c.221A>T]. The new variant results from a double nucleotide mutation at the same codon. The possible molecular mechanisms are discussed. PMID:25476778

Renoux, Céline; Feray, Cécile; Joly, Philippe; Zanella-Cleon, Isabelle; Garcia, Caroline; Lacan, Philippe; Couprie, Nicole; Francina, Alain

2015-01-01

8

Seamless gene correction of ?-thalassemia mutations in patient-specific iPSCs using CRISPR/Cas9 and piggyBac  

PubMed Central

?-thalassemia, one of the most common genetic diseases worldwide, is caused by mutations in the human hemoglobin beta (HBB) gene. Creation of human induced pluripotent stem cells (iPSCs) from ?-thalassemia patients could offer an approach to cure this disease. Correction of the disease-causing mutations in iPSCs could restore normal function and provide a rich source of cells for transplantation. In this study, we used the latest gene-editing tool, CRISPR/Cas9 technology, combined with the piggyBac transposon to efficiently correct the HBB mutations in patient-derived iPSCs without leaving any residual footprint. No off-target effects were detected in the corrected iPSCs, and the cells retain full pluripotency and exhibit normal karyotypes. When differentiated into erythroblasts using a monolayer culture, gene-corrected iPSCs restored expression of HBB compared to the parental iPSCs line. Our study provides an effective approach to correct HBB mutations without leaving any genetic footprint in patient-derived iPSCs, thereby demonstrating a critical step toward the future application of stem cell-based gene therapy to monogenic diseases. PMID:25096406

Xie, Fei; Ye, Lin; Chang, Judy C.; Beyer, Ashley I.; Wang, Jiaming; Muench, Marcus O.

2014-01-01

9

Production of Gene-Corrected Adult Beta Globin Protein in Human Erythrocytes Differentiated from Patient iPSCs After Genome Editing of the Sickle Point Mutation.  

PubMed

Human induced pluripotent stem cells (iPSCs) and genome editing provide a precise way to generate gene-corrected cells for disease modeling and cell therapies. Human iPSCs generated from sickle cell disease (SCD) patients have a homozygous missense point mutation in the HBB gene encoding adult ?-globin proteins, and are used as a model system to improve strategies of human gene therapy. We demonstrate that the CRISPR/Cas9 system designer nuclease is much more efficient in stimulating gene targeting of the endogenous HBB locus near the SCD point mutation in human iPSCs than zinc finger nucleases and TALENs. Using a specific guide RNA and Cas9, we readily corrected one allele of the SCD HBB gene in human iPSCs by homologous recombination with a donor DNA template containing the wild-type HBB DNA and a selection cassette that was subsequently removed to avoid possible interference of HBB transcription and translation. We chose targeted iPSC clones that have one corrected and one disrupted SCD allele for erythroid differentiation assays, using an improved xeno-free and feeder-free culture condition we recently established. Erythrocytes from either the corrected or its parental (uncorrected) iPSC line were generated with similar efficiencies. Currently ?6%-10% of these differentiated erythrocytes indeed lacked nuclei, characteristic of further matured erythrocytes called reticulocytes. We also detected the 16-kDa ?-globin protein expressed from the corrected HBB allele in the erythrocytes differentiated from genome-edited iPSCs. Our results represent a significant step toward the clinical applications of genome editing using patient-derived iPSCs to generate disease-free cells for cell and gene therapies. Stem Cells 2015;33:1470-1479. PMID:25702619

Huang, Xiaosong; Wang, Ying; Yan, Wei; Smith, Cory; Ye, Zhaohui; Wang, Jing; Gao, Yongxing; Mendelsohn, Laurel; Cheng, Linzhao

2015-05-01

10

Beta-globin gene haplotypes among cameroonians and review of the global distribution: is there a case for a single sickle mutation origin in Africa?  

PubMed

Studies of hemoglobin S haplotypes in African subpopulations have potential implications for patient care and our understanding of genetic factors that have shaped the prevalence of sickle cell disease (SCD). We evaluated HBB gene cluster haplotypes in SCD patients from Cameroon, and reviewed the literature for a global distribution. We reviewed medical records to obtain pertinent socio-demographic and clinical features for 610 Cameroonian SCD patients, including hemoglobin electrophoresis and full blood counts. RFLP-PCR was used to determine the HBB gene haplotype on 1082 chromosomes. A systematic review of the current literature was undertaken to catalogue HBB haplotype frequencies in SCD populations around the world. Benin (74%; n=799) and Cameroon (19%; n=207) were the most prevalent haplotypes observed among Cameroonian patients. There was no significant association between HBB haplotypes and clinical life events, anthropometric measures, hematological parameters, or fetal hemoglobin (HbF) levels. The literature review of the global haplotype distributions was consistent with known historical migrations of the people of Africa. Previously reported data from Sudan showed a distinctly unusual pattern; all four classical haplotypes were reported, with an exceptionally high proportion of the Senegal, Cameroon, and atypical haplotypes. We did not observe any significant associations between HBB haplotype and SCD disease course in this cohort. Taken together, the data from Cameroon and from the wider literature suggest that a careful reassessment of African HBB haplotypes may shed further light on the evolutionary dynamics of the sickle allele, which could suggest a single origin of the sickle mutation. PMID:25748438

Bitoungui, Valentina J Ngo; Pule, Gift D; Hanchard, Neil; Ngogang, Jeanne; Wonkam, Ambroise

2015-03-01

11

The Human Gene Mutation Database  

NSDL National Science Digital Library

The Human Gene Mutation Database from the Institute of Medical Genetics at Cardiff provides practical information for researchers, physicians, and genetic counselors. The database is currently undergoing some reorganization, but information can be searched by "disease, gene name, or gene symbol." Search results are well organized and easy to navigate, linking directly to results from external Web databases without requiring that the user perform additional searches. Frequent users may also appreciate the listing of genes recently added to the database.

12

Hb Feilding [?12(A9)Thr???Pro; HBB: c.37A>C]: A Novel Unstable ?-Globin Chain Variant.  

PubMed

Abstract We report here a patient heterozygous for a previously unreported ? chain variant. A 72-year-old Caucasian female was found to have an abnormal hemoglobin (Hb) as an incidental finding following Hb A1C analysis. There was no family history of anemia or hemoglobinopathy. Her full blood count revealed a mild normochromic anemia with Hb 11.1 g/dL (range 11.5-15.0), mean corpuscular volume (MCV) 93.0 fL (range 80.0-100.0) and mean corpuscular Hb (MCH) 30.0 pg (range 27.0-32.0). Isopropanol stability tests and a variant Hb on high performance liquid chromatography (HPLC) comprizing 37.0% of the total Hb suggested an unstable Hb variant. Sanger sequencing of the ?-globin gene revealed a single base substitution, HBB: c.37A>C, causing the missense mutation ?12(A9)Thr???Pro in exon 1 of the HBB gene. This mutation changes the threonine residue at position 12(A9) to a proline in the ?-globin chain. We propose that this variant be called Hb Feilding after the town where the proband lived. Three dimensional modeling suggested that the disruption of the Hb structure was due to the introduction of a proline at helix A9 which caused distortion of the helical structure and resulted in reduced solubility. PMID:25572184

Ghallyan, Nikhil; Donald, Tarn; Broad, David; Johnson, Steve; Browett, Peter; Van de Water, Neil

2015-01-01

13

Localised Sex, Contingency and Mutator Genes  

E-print Network

;Consequences of Asexual Reproduction Mutation Clonal Population: highly structured with low diversity, bottlenecking, back mutations #12;Mutation and mutator genes · In asexual reproduction, novelty introduced) § Reproduction § Architecture-Alteration (deletion/duplication) #12;Adaptation and Optimization · Natural

Atkinson, Katie

14

Rare hemoglobin variants: Hb G-Szuhu (HBB: c.243C>G), Hb G-Coushatta (HBB: c.68A>C) and Hb Mizuho (HBB: c.206T>C) in Sri Lankan families.  

PubMed

In this short communication, we describe the clinical presentation of unusual hemoglobin (Hb), variants in three Sri Lankan cases under study for ?-thalassemia intermedia (?-TI). We believe this is the first report on their occurrence in Sri Lanka as well as from the Indian subcontinent. During a molecular study performed on ?-TI patients, we identified three unusual Hb variants as Hb G-Szuhu (HBB: c.243C>G), Hb G-Coushatta (HBB: c.68A>C) and Hb Mizuho (HBB: c.206T>C) in three unrelated families. Hb G-Szuhu and Hb G-Coushatta were found in combination with the common ?-thalassemia (?-thal) mutation, IVS-I-5 (G>C). Both probands had mild anemia with greatly reduced red cell indices and had non palpable livers and spleens, however, by ultrasound, both were observed to be enlarged. The final Hb variant, Hb Mizuho, was identified as a heterozygous mutation found in both proband and his mother. Both family members had severe anemia and were regularly transfused and had increased red cell parameters. PMID:25572187

Perera, P Shiromi; Silva, Ishari; Hapugoda, Menaka; Wickramarathne, Merita N; Wijesiriwardena, Indira; Efremov, Dimitar G; Fisher, Christopher A; Weatherall, David J; Premawardhena, Anuja

2015-01-01

15

The Androgen Receptor Gene Mutations Database  

Microsoft Academic Search

The current version of the androgen receptor (AR) gene mutations database is described. The total number of reported mutations has risen from 272 to 309 in the past year. We have expanded the database: (i) by giving each entry an accession number; (ii) by adding information on the length of polymorphic polyglutamine (polyGln) and polyglycine (polyGly) tracts in exon 1;

Bruce Gottlieb; Heikki Lehväslaiho; Lenore K. Beitel; Rose Lumbroso; Leonard Pinsky; Mark Trifiro

1998-01-01

16

From Gene Mutation to Protein Characterization  

ERIC Educational Resources Information Center

A seven-week "gene to protein" laboratory sequence is described for an undergraduate biochemistry laboratory course. Student pairs were given the task of introducing a point mutation of their choosing into the well studied protein, enhanced green fluorescent protein (EGFP). After conducting literature searches, each student group chose the…

Moffet, David A.

2009-01-01

17

The Wilson disease gene: Haplotypes and mutations  

SciTech Connect

Wilson disease (WND) is an autosomal recessive defect of copper transport. The gene involved in WND, located on chromosome 13, has recently been shown to be a putative copper transporting P-type ATPase, designated ATP7B. The gene is highly similar to ATP7A, located on the X chromosome, which is defective in Menkes disease, another disorder of copper transport. We have available for study WND families from Canada (34 families), the United Kingdom (32 families), Japan (4 families), Iceland (3 families) and Hong Kong (2 families). We have utilized four highly polymorphic CA repeat markers (D13S296, D13S301, D13S314 and D13S316) surrounding the ATP7B locus to construct haplotypes in these families. Analysis indicates that there are many unique WND haplotypes not present on normal chromosomes and that there may be a large number of different WND mutations. We have screened the WND patients for mutations in the ATP7B gene. Fifty six patients, representing all of the identified haplotypes, have been screened using single strand conformational polymorphism (SSCP), followed by selective sequencing. To date, 19 mutations and 12 polymorphisms have been identified. All of the changes are nucleotide substitutions or small insertions/deletions and there is no evidence for larger deletions as seen in the similar gene on the X chromosome, ATP7A. Haplotypes of close markers and the ability to detect some of the mutations present in the gene allow for more reliable molecular diagnosis of presymptomatic sibs of WND patients. A reassessment of individuals previously diagnosed in the presymptomatic phase is now required, as we have have identified some heterozygotes who are biochemically indistinguishable from affected homozygotes. The identification of specific mutations will soon allow direct diagnosis of WND patients with a high level of certainty.

Thomas, G.R.; Roberts, E.A.; Cox, D.W. [Hospital for Sick Children, Toronto (Canada); Walshe, J.M. [Middlesex Hospital, London (United Kingdom)

1994-09-01

18

p53 gene mutation: software and database.  

PubMed Central

A large number of different mutations in the p53 tumor suppressor gene have been identified in all types of cancer. As of October, 1997, this database (http:// perso.curie.fr/tsoussi ) contained >7500 mutations. Such a substantial increase since our previous reports should enable epidemiological analyses which were not previously possible. In order to analyse these new data, the UMD software has been improved. A new Web version of the UMD software enables online analysis of the database. The present report describes various improvements since the last release of the database. PMID:9399836

Béroud, C; Soussi, T

1998-01-01

19

The Human Gene Mutation Database: 2008 update.  

PubMed

The Human Gene Mutation Database (HGMD((R))) is a comprehensive core collection of germline mutations in nuclear genes that underlie or are associated with human inherited disease. Here, we summarize the history of the database and its current resources. By December 2008, the database contained over 85,000 different lesions detected in 3,253 different genes, with new entries currently accumulating at a rate exceeding 9,000 per annum. Although originally established for the scientific study of mutational mechanisms in human genes, HGMD has since acquired a much broader utility for researchers, physicians, clinicians and genetic counselors as well as for companies specializing in biopharmaceuticals, bioinformatics and personalized genomics. HGMD was first made publicly available in April 1996, and a collaboration was initiated in 2006 between HGMD and BIOBASE GmbH. This cooperative agreement covers the exclusive worldwide marketing of the most up-to-date (subscription) version of HGMD, HGMD Professional, to academic, clinical and commercial users. PMID:19348700

Stenson, Peter D; Mort, Matthew; Ball, Edward V; Howells, Katy; Phillips, Andrew D; Thomas, Nick St; Cooper, David N

2009-01-01

20

Towards linked open gene mutations data  

PubMed Central

Background With the advent of high-throughput technologies, a great wealth of variation data is being produced. Such information may constitute the basis for correlation analyses between genotypes and phenotypes and, in the future, for personalized medicine. Several databases on gene variation exist, but this kind of information is still scarce in the Semantic Web framework. In this paper, we discuss issues related to the integration of mutation data in the Linked Open Data infrastructure, part of the Semantic Web framework. We present the development of a mapping from the IARC TP53 Mutation database to RDF and the implementation of servers publishing this data. Methods A version of the IARC TP53 Mutation database implemented in a relational database was used as first test set. Automatic mappings to RDF were first created by using D2RQ and later manually refined by introducing concepts and properties from domain vocabularies and ontologies, as well as links to Linked Open Data implementations of various systems of biomedical interest. Since D2RQ query performances are lower than those that can be achieved by using an RDF archive, generated data was also loaded into a dedicated system based on tools from the Jena software suite. Results We have implemented a D2RQ Server for TP53 mutation data, providing data on a subset of the IARC database, including gene variations, somatic mutations, and bibliographic references. The server allows to browse the RDF graph by using links both between classes and to external systems. An alternative interface offers improved performances for SPARQL queries. The resulting data can be explored by using any Semantic Web browser or application. Conclusions This has been the first case of a mutation database exposed as Linked Data. A revised version of our prototype, including further concepts and IARC TP53 Mutation database data sets, is under development. The publication of variation information as Linked Data opens new perspectives: the exploitation of SPARQL searches on mutation data and other biological databases may support data retrieval which is presently not possible. Moreover, reasoning on integrated variation data may support discoveries towards personalized medicine. PMID:22536974

2012-01-01

21

TERATOGENIC EVALUATION AND FETAL DEPOSITION OF HEXABROMOBENZENE (HBB) AND HEXAFLUOROBENZENE (HFB) IN CD-1 MICE  

EPA Science Inventory

HBB (hexabromobenzene) and HFB (hexafluorobenzene) were tested for their teratogenic potential in CD-1 mice. HBB and HFB were administered to pregnant mice from the 6th to the 16th day of gestation by gastric intubation. Neither HBB nor HFB were teratogenic or fetotoxic at doses ...

22

Novel recurrently mutated genes in African American colon cancers.  

PubMed

We used whole-exome and targeted sequencing to characterize somatic mutations in 103 colorectal cancers (CRC) from African Americans, identifying 20 new genes as significantly mutated in CRC. Resequencing 129 Caucasian derived CRCs confirmed a 15-gene set as a preferential target for mutations in African American CRCs. Two predominant genes, ephrin type A receptor 6 (EPHA6) and folliculin (FLCN), with mutations exclusive to African American CRCs, are by genetic and biological criteria highly likely African American CRC driver genes. These previously unsuspected differences in the mutational landscapes of CRCs arising among individuals of different ethnicities have potential to impact on broader disparities in cancer behaviors. PMID:25583493

Guda, Kishore; Veigl, Martina L; Varadan, Vinay; Nosrati, Arman; Ravi, Lakshmeswari; Lutterbaugh, James; Beard, Lydia; Willson, James K V; Sedwick, W David; Wang, Zhenghe John; Molyneaux, Neil; Miron, Alexander; Adams, Mark D; Elston, Robert C; Markowitz, Sanford D; Willis, Joseph E

2015-01-27

23

Gene Mutations Linked to Colon Cancer in Black Patients  

MedlinePLUS

... JavaScript. Gene Mutations Linked to Colon Cancer in Black Patients Finding might lead to better treatment of ... Preidt Tuesday, January 13, 2015 Related MedlinePlus Pages African American Health Colorectal Cancer Genes and Gene Therapy TUESDAY, ...

24

Polymorphisms in the bovine hemoglobin-beta gene provide evidence for gene-flow between wild species of Bos (Bibos) and domestic cattle in Southeast Asia.  

PubMed

The electrophoretic variation in bovine hemoglobin-beta (HBB) is one of the most investigated genetic markers. The presence of a unique HBB variant, HBB(X), in Southeast Asian cattle has been reputed as a sign of gene-flow from wild bovine species. In this study, we analyzed the DNA sequences of HBB genes in domestic and wild bovine species to verify this belief. Isoelectric focusing of HBB chain revealed that the HBB(X) in domestic cattle had dimorphism and was separated into HBB(X1) and HBB(X2). The HBB(X1) had the same DNA sequence of the common HBB variant in gayal (Bos gaurus frontalis), while some of the HBB(X2) were identical with that of Cambodian banteng (Bos javanicus birmanicus). As a result, we confirmed that the bovine HBB variants can be a good indicator of introgression between wild and domestic cattle. The HBB(X1) was always predominant to HBB(X2) in the continental populations, suggesting that the gaur had contributed to the gene pool of domestic cattle in this region much more than the banteng. On the other hand, the mitochondrial DNA analysis could not detect gene-flow from wild species. Autosomal markers that can trace the phylogeny between alleles are suitable for the assessment of bovine interspecific introgression. PMID:21269357

Tanaka, Kazuaki; Takizawa, Tatsuya; Dorji, Tashi; Amano, Takashi; Mannen, Hideyuki; Maeda, Yoshizane; Yamamoto, Yoshio; Namikawa, Takao

2011-02-01

25

Gene promoter hypermethylation in ductal lavage fluid from healthy BRCA gene mutation carriers and mutation-negative controls  

Microsoft Academic Search

INTRODUCTION: Female germline BRCA gene mutation carriers are at increased risk for developing breast cancer. The purpose of our study was to establish whether healthy BRCA mutation carriers demonstrate an increased frequency of aberrant gene promoter hypermethylation in ductal lavage (DL) fluid, compared with predictive genetic test negative controls, that might serve as a surrogate marker of BRCA1\\/2 mutation status

Imogen Locke; Zsofia Kote-Jarai; Mary Jo Fackler; Elizabeth Bancroft; Peter Osin; Ashutosh Nerurkar; Louise Izatt; Gabriella Pichert; Gerald PH Gui; Rosalind A Eeles

2007-01-01

26

Recurrent mutation in the human phenylalanine hydroxylase gene.  

PubMed Central

We report the identification of a missense mutation of Glu280 to Lys280 in the phenylalanine hydroxylase (PAH) gene of a phenylketonuria (PKU) patient in Denmark. The mutation is associated with haplotype 1 of the PAH gene in this population. This mutation has previously been found in North Africa, where it is in linkage disequilibrium with haplotype 38. While it is conceivable that this mutation could have been transferred from one haplotype background to another by a double crossover or gene conversion event, the fact that the mutation is exclusively associated with the two different haplotypes in the two distinct populations supports the hypothesis that these two PKU alleles are the result of recurrent mutations in the human PAH gene. Furthermore, since the site of mutation involves a CpG dinucleotide, they may represent hot spots for mutation in the human PAH locus. Images Figure 1 Figure 2 PMID:1971144

Okano, Y; Wang, T; Eisensmith, R C; Güttler, F; Woo, S L

1990-01-01

27

The FASEB Journal Review Combinatorial patterns of somatic gene mutations  

E-print Network

. For instance, mutations of genes in the Ras and Wnt pathways tend to co-occur in the large intestine but are mutually exclusive in cancers of the pancreas. The relationships between mutations in different samples

Yeang, Chen-Hsiang

28

[Somatic mutations of the P53 gene in stomach cancer].  

PubMed

The paper deals with a study of p53 gene somatic mutations in tumor cell genomes from patients with stomach cancers of different histological patterns. It used sequential and molecular cloning methods. The former involved amplicones characterized by abnormal volatility following SSCP analysis of plasmids from 9 tumors. Replacement nucleotides were identified in 4 tumors (intestinal--2, diffuse--2). Among 8 mutations were 1 single-nucleotide deletion in codon-249 with shifting sensing frame and one targeted mutation. Five of the former were missens-mutations which caused amino acid replacement while the other two silent mutations did not. Exon-assisted analysis of p53 ("wild") gene identified cells with stable structure in each tumor (1 mutation--2; 3 mutations--2 including genuinely-paired mutations in 1 exon). All mutations occurred in structurally and functionally important codons. Our evidence corroborated earlier data of SSCP analysis on tumor cell presence in populations with variable p53 genomes. PMID:20552890

Beliavskaia, V A; Vardosanidze, K V; Oreshkova, S F; Blinov, A G; Ternovo?, V A; Blinov, V M; Cherdyntseva, N V; Voevoda, M I

2010-01-01

29

Gene Mutations Tied to Leukemia Rise with Age, Study Finds  

MedlinePLUS

... sharing features on this page, please enable JavaScript. Gene Mutations Tied to Leukemia Rise With Age, Study ... than 90, have blood cells with the same gene changes seen in leukemia. Just carrying a particular ...

30

Overview of skin diseases linked to connexin gene mutations.  

PubMed

Mutations in skin-expressed connexin genes, such as connexins 26, 30, 30.3, 31, and 43, have been linked to several human hereditary diseases with multiple organ involvement. Mutations in connexin 26 are linked to diseases including Vohwinkel syndrome, keratitis-ichthyosis deafness, and hystrix-like ichthyosis deafness syndromes, palmoplantar keratoderma with deafness, deafness with Clouston-like phenotype, and Bart-Pumphrey syndrome. Mutations in connexin 30 are correlated with Clouston syndrome. Connexin 30.3 and 31 mutations lead to erythrokeratoderma variabilis, and mutations in connexin 43 are correlated with oculodentodigital dysplasia. Provided is a review of these mutations and related skin disorders. PMID:23675785

Avshalumova, Lyubov; Fabrikant, Jordan; Koriakos, Angie

2014-02-01

31

Clonal diversity of recurrently mutated genes in myelodysplastic syndromes  

PubMed Central

Recent studies suggest that most cases of myelodysplastic syndrome (MDS) are clonally heterogeneous, with a founding clone and multiple subclones. It is not known whether specific gene mutations typically occur in founding clones or subclones. We screened a panel of 94 candidate genes in a cohort of 157 patients with MDS or secondary acute myeloid leukemia (sAML). This included 150 cases with samples obtained at MDS diagnosis and 15 cases with samples obtained at sAML transformation (8 were also analyzed at the MDS stage). We performed whole-genome sequencing (WGS) to define the clonal architecture in eight sAML genomes and identified the range of variant allele frequencies (VAFs) for founding clone mutations. At least one mutation or cytogenetic abnormality was detected in 83% of the 150 MDS patients and 17 genes were significantly mutated (false discovery rate ?0.05). Individual genes and patient samples displayed a wide range of VAFs for recurrently mutated genes, indicating that no single gene is exclusively mutated in the founding clone. The VAFs of recurrently mutated genes did not fully recapitulate the clonal architecture defined by WGS, suggesting that comprehensive sequencing may be required to accurately assess the clonal status of recurrently mutated genes in MDS. PMID:23443460

Walter, MJ; Shen, D; Shao, J; Ding, L; White, BS; Kandoth, C; Miller, CA; Niu, B; McLellan, MD; Dees, ND; Fulton, R; Elliot, K; Heath, S; Grillot, M; Westervelt, P; Link, DC; DiPersio, JF; Mardis, E; Ley, TJ; Wilson, RK; Graubert, TA

2013-01-01

32

Absence of ras gene mutations in early gastric carcinomas  

Microsoft Academic Search

The aims of this study were to assess the prevalence and type of activating point mutations at codons 12, 13, and 61 of the Ki-, Ha-, and N-ras genes in a series of early gastric carcinomas in white patients and to correlate these ras gene mutations, if any, with the histological type (Lauren classification), the type of growth pattern, and

M E Craanen; P Blok; B Top; L Boerrigter; W Dekker; G J Offerhaus; G N Tytgat; S Rodenhuis

1995-01-01

33

ras Gene mutations in oral cancer in eastern India  

Microsoft Academic Search

Oral tumor specimens (n=50) from eastern Indian population were studied for the presence of mutations in the H-, K- and N-ras genes using selective oligodeoxynucleotide hybridization and restriction fragment length polymorphism analysis of polymerase chain reaction-amplified products. Mutations in H- and K-ras genes were observed at a frequency of 28 and 33%, respectively, whereas no N-ras mutation was noticed.

N Das; J Majumder; U. B DasGupta

2000-01-01

34

Gene Expression in the Star Mutation of Petunia x Hybrida  

Technology Transfer Automated Retrieval System (TEKTRAN)

Differences in structural gene expression are responsible for a wide range of responses from human cancer to patterned flowers. Gene silencing is one of the ways in which gene expression is controlled. We have developed a model system to study anthocyanin gene silencing using a mutation in Petunia ...

35

Novel recurrently mutated genes and a prognostic mutation signature in colorectal cancer  

PubMed Central

Background Characterisation of colorectal cancer (CRC) genomes by next-generation sequencing has led to the discovery of novel recurrently mutated genes. Nevertheless, genomic data has not yet been used for CRC prognostication. Objective To identify recurrent somatic mutations with prognostic significance in patients with CRC. Method Exome sequencing was performed to identify somatic mutations in tumour tissues of 22 patients with CRC, followed by validation of 187 recurrent and pathway-related genes using targeted capture sequencing in additional 160 cases. Results Seven significantly mutated genes, including four reported (APC, TP53, KRAS and SMAD4) and three novel recurrently mutated genes (CDH10, FAT4 and DOCK2), exhibited high mutation prevalence (6–14% for novel cancer genes) and higher-than-expected number of non-silent mutations in our CRC cohort. For prognostication, a five-gene-signature (CDH10, COL6A3, SMAD4, TMEM132D, VCAN) was devised, in which mutation(s) in one or more of these genes was significantly associated with better overall survival independent of tumor-node-metastasis (TNM) staging. The median survival time was 80.4?months in the mutant group versus 42.4?months in the wild type group (p=0.0051). The prognostic significance of this signature was successfully verified using the data set from the Cancer Genome Atlas study. Conclusions The application of next-generation sequencing has led to the identification of three novel significantly mutated genes in CRC and a mutation signature that predicts survival outcomes for stratifying patients with CRC independent of TNM staging. PMID:24951259

Yu, Jun; Wu, William K K; Li, Xiangchun; He, Jun; Li, Xiao-Xing; Ng, Simon S M; Yu, Chang; Gao, Zhibo; Yang, Jie; Li, Miao; Wang, Qiaoxiu; Liang, Qiaoyi; Pan, Yi; Tong, Joanna H; To, Ka F; Wong, Nathalie; Zhang, Ning; Chen, Jie; Lu, Youyong; Lai, Paul B S; Chan, Francis K L; Li, Yingrui; Kung, Hsiang-Fu; Yang, Huanming; Wang, Jun; Sung, Joseph J Y

2015-01-01

36

Methods for detecting mutations in the human JAK2 gene.  

PubMed

Mutations in the JAK2 gene are prevalent in the human myeloid malignancies, being present in virtually all cases of polycythemia vera, and a significant proportion of patients with other myeloproliferative disorders. Various methods for the detection of acquired mutations in this gene are available depending on the need for sensitivity, quantification, or the ability to detect many different mutations. We summarize the various methods published and discuss their relative merits for each application. Two commonly used methods, quantitative real-time PCR (QPCR) for the detection of the JAK2 V617F mutation and high resolution melt-curve analysis (HRM) for the detection of multiple mutations within JAK2 exon 12, demonstrate the utility of each method and their limitations. The choice of methodology is dependent on the application; therefore there is no gold standard for detecting mutations in this gene. PMID:23296725

Bench, Anthony J; Baxter, E Joanna; Green, Anthony R

2013-01-01

37

Mutations of the BRAF gene in human cancer  

Microsoft Academic Search

Cancers arise owing to the accumulation of mutations in critical genes that alter normal programmes of cell proliferation, differentiation and death. As the first stage of a systematic genome-wide screen for these genes, we have prioritized for analysis signalling pathways in which at least one gene is mutated in human cancer. The RAS-RAF-MEK-ERK-MAP kinase pathway mediates cellular responses to growth

Helen Davies; Graham R. Bignell; Charles Cox; Philip Stephens; Sarah Edkins; Sheila Clegg; Jon Teague; Hayley Woffendin; Mathew J. Garnett; William Bottomley; Neil Davis; Ed Dicks; Rebecca Ewing; Yvonne Floyd; Kristian Gray; Sarah Hall; Rachel Hawes; Jaime Hughes; Vivian Kosmidou; Andrew Menzies; Catherine Mould; Adrian Parker; Claire Stevens; Stephen Watt; Steven Hooper; Rebecca Wilson; Hiran Jayatilake; Barry A. Gusterson; Colin Cooper; Janet Shipley; Darren Hargrave; Katherine Pritchard-Jones; Norman Maitland; Georgia Chenevix-Trench; Gregory J. Riggins; Darell D. Bigner; Giuseppe Palmieri; Antonio Cossu; Adrienne Flanagan; Andrew Nicholson; Judy W. C. Ho; Suet Y. Leung; Siu T. Yuen; Barbara L. Weber; Hilliard F. Seigler; Timothy L. Darrow; Hugh Paterson; Richard Marais; Christopher J. Marshall; Richard Wooster; Michael R. Stratton; P. Andrew Futreal

2002-01-01

38

Modeling Autism by SHANK Gene Mutations in Mice  

PubMed Central

Summary Shank family proteins (Shank1, Shank2, and Shank3) are synaptic scaffolding proteins that organize an extensive protein complex at the postsynaptic density (PSD) of excitatory glutamatergic synapses. Recent human genetic studies indicate that SHANK family genes (SHANK1, SHANK2, and SHANK3) are causative genes for idiopathic autism spectrum disorders (ASD). Neurobiological studies of Shank mutations in mice support a general hypothesis of synaptic dysfunction in the pathophysiology of ASD. However, the molecular diversity of SHANK family gene products, as well as the heterogeneity in human and mouse phenotypes, pose challenges to modeling human SHANK mutations. Here, we review the molecular genetics of SHANK mutations in human ASD and discuss recent findings where such mutations have been modeled in mice. Conserved features of synaptic dysfunction and corresponding behaviors in Shank mouse mutants may help dissect the pathophysiology of ASD, but also highlight divergent phenotypes that arise from different mutations in the same gene. PMID:23583105

Jiang, Yong-hui; Ehlers, Michael D.

2013-01-01

39

Novel KRAS Gene Mutations in Sporadic Colorectal Cancer  

PubMed Central

Introduction In this article, we report 7 novel KRAS gene mutations discovered while retrospectively studying the prevalence and pattern of KRAS mutations in cancerous tissue obtained from 56 Saudi sporadic colorectal cancer patients from the Eastern Province. Methods Genomic DNA was extracted from formalin-fixed, paraffin-embedded cancerous and noncancerous colorectal tissues. Successful and specific PCR products were then bi-directionally sequenced to detect exon 4 mutations while Mutector II Detection Kits were used for identifying mutations in codons 12, 13 and 61. The functional impact of the novel mutations was assessed using bioinformatics tools and molecular modeling. Results KRAS gene mutations were detected in the cancer tissue of 24 cases (42.85%). Of these, 11 had exon 4 mutations (19.64%). They harbored 8 different mutations all of which except two altered the KRAS protein amino acid sequence and all except one were novel as revealed by COSMIC database. The detected novel mutations were found to be somatic. One mutation is predicted to be benign. The remaining mutations are predicted to cause substantial changes in the protein structure. Of these, the Q150X nonsense mutation is the second truncating mutation to be reported in colorectal cancer in the literature. Conclusions Our discovery of novel exon 4 KRAS mutations that are, so far, unique to Saudi colorectal cancer patients may be attributed to environmental factors and/or racial/ethnic variations due to genetic differences. Alternatively, it may be related to paucity of clinical studies on mutations other than those in codons 12, 13, 61 and 146. Further KRAS testing on a large number of patients of various ethnicities, particularly beyond the most common hotspot alleles in exons 2 and 3 is needed to assess the prevalence and explore the exact prognostic and predictive significance of the discovered novel mutations as well as their possible role in colorectal carcinogenesis. PMID:25412182

Naser, Walid M.; Shawarby, Mohamed A.; Al-Tamimi, Dalal M.; Seth, Arun; Al-Quorain, Abdulaziz; Nemer, Areej M. Al; Albagha, Omar M. E.

2014-01-01

40

CFTR gene mutations in isolated chronic obstructive pulmonary disease  

SciTech Connect

In order to identify a possible hereditary predisposition to the development of chronic obstructive pulmonary disease (COPD), we have looked for the presence of cystic fibrosis transmembrane regulator (CFTR) gene DNA sequence modifications in 28 unrelated patients with no signs of cystic fibrosis. The known mutations in Italian CF patients, as well as the most frequent worldwide CF mutations, were investigated. In addition, a denaturing gradient gel electrophoresis analysis of about half of the coding sequence of the gene in 56 chromosomes from the patients and in 102 chromosomes from control individuals affected by other pulmonary diseases and from normal controls was performed. Nine different CFTR gene mutations and polymorphisms were found in seven patients, a highly significant increase over controls. Two of the patients were compound heterozygotes. Two frequent CF mutations were detected: deletion F508 and R117H; two rare CF mutations: R1066C and 3667ins4; and five CF sequence variants: R75Q (which was also described as a disease-causing mutation in male sterility cases due to the absence of the vasa deferentia), G576A, 2736 A{r_arrow}G, L997F, and 3271+18C{r_arrow}T. Seven (78%) of the mutations are localized in transmembrane domains. Six (86%) of the patients with defined mutations and polymorphisms had bronchiectasis. These results indicate that CFTR gene mutations and sequence alterations may be involved in the etiopathogenesis of some cases of COPD.

Pignatti, P.F.; Bombien, C.; Marigo, C. [and others

1994-09-01

41

Amelogenesis Imperfecta and Screening of Mutation in Amelogenin Gene  

PubMed Central

The aim of this study was to report the clinical findings and the screening of mutations of amelogenin gene of a 7-year-old boy with amelogenesis imperfecta (AI). The genomic DNA was extracted from saliva of patient and his family, followed by PCR and direct DNA sequencing. The c.261C>T mutation was found in samples of mother, father, and brother, but the mutation was not found in the sequence of the patient. This mutation is a silent mutation and a single-nucleotide polymorphism (rs2106416). Thus, it is suggested that the mutation found was not related to the clinical presence of AI. Further research is necessary to examine larger number of patients and genes related to AI. PMID:25045544

Oliveira, Fernanda Veronese; Gurgel, Carla Vecchione; Kobayashi, Tatiana Yuriko; Dionísio, Thiago José; Neves, Lucimara Teixeira; Santos, Carlos Ferreira; Machado, Maria Aparecida Andrade Moreira

2014-01-01

42

?-Globin Mutations in Egyptian Patients With ?-Thalassemia.  

PubMed

?-thalassemia is a common hereditary disorder, particularly in Middle Eastern countries. More than 200 mutations in the ? globin gene have been reported; most are point mutations in functionally important regions (HBB; OMIM #141900)). The spectrum of mutations varies significantly between different geographical regions; only a few common mutations of ?-globin cause ?-thalassemia in each population. The aim of this study was to determine the spectrum of mutations that cause ?-thalassemia in the North Coast of Egypt and to investigate their correlation with the phenotypic severity of ?-thalassemia. We carried out our study with a total of 47 Egyptian patients (25 male and 22 female) confirmed to have ?-thalassemia. Evaluation of ?-thalassemia mutations revealed the presence of 10 ?-globin mutations. The most frequently encountered mutations were intronic: IVS 1.6 [T>C] (27.66%) and IVS 1.110 [G>A] (22.35%), followed by IVS 2.848 [C>A], IVS 1.1 (G>A), and IVS 2.745 [C>G]. We observed the exonic and promoter mutations less frequently. A homozygous mutation was found in 24 patients (51%) and compound heterozygous mutations were found in 13 patients (28%). However, in 9 patients (19%), we identified only 1 mutation. In 1 patient (2%), we detected no mutation. The detection rate of the method that we used in our population was 88% (83 of the tested 94 alleles). The results we obtained did not reveal any correlation between genotype and phenotype among patients with ?-thalassemia. PMID:25617386

Elmezayen, Ammar D; Kotb, Samia M; Sadek, Nadia A; Abdalla, Ebtesam M

2015-01-01

43

Preservation of Duplicate Genes by Complementary, Degenerative Mutations  

Microsoft Academic Search

The origin of organismal complexity is generally thought to be tightly coupled to the evolution of new gene functions arising subsequent to gene duplication. Under the classical model for the evolution of duplicate genes, one member of the duplicated pair usually degenerates within a few million years by accumulating deleterious mutations, while the other duplicate retains the original function. This

Allan Force; Michael Lynch; F. Bryan Pickett; Angel Amores; Yi-lin Yan; John Postlethwait

1999-01-01

44

Diverse growth hormone receptor gene mutations in Laron syndrome  

SciTech Connect

To better understand the molecular genetic basis and genetic epidemiology of Laron syndrome (growth-hormone insensitivity syndrome), the authors analysed the growth-hormone receptor (GHR) genes of seven unrelated affected individuals from the United States, South America, Europe, and Africa. They amplified all nine GHR gene exons and splice junctions from these individuals by PCR and screened the products for mutations by using denaturing gradient gel electrophoresis (DGGE). They identified a single GHR gene fragment with abnormal DGGE results for each affected individual, sequenced this fragment, and, in each case, identified a mutation likely to cause Laron syndrome, including two nonsense mutations (R43X and R217X), two splice-junction mutations, (189-1 G to T and 71+1 G to A), and two frameshift mutations (46 del TT and 230 del TA or AT). Only one of these mutations, R43X, has been previously reported. Using haplotype analysis, they determined that this mutation, which involves a CpG dinucleotide hot spot, likely arose as a separate event in this case, relative to the two prior reports of R43X. Aside from R43X, the mutations identified are unique to patients from particular geographic regions. Ten GHR gene mutations have now been described in this disorder. The authors conclude that Laron syndrome is caused by diverse GHR gene mutations, including deletions, RNA processing defects, translational stop codons, and missense codons. All the identified mutations involve the extracellular domain of the receptor, and most are unique to particular families or geographic areas. 35 refs., 3 figs., 1 tab.

Berg, M.A.; Francke, U. (Stanford Univ. School of Medicine, CA (United States)); Gracia, R.; Rosenbloom, A.; Toledo, S.P.A. (Univ. Autonoma, Madrid (Spain)); Chernausek, S. (Children's Hospital Medical Center, Cincinnati, OH (United States)); Guevara-Aguirre, J. (Institute of Endocrinology, Metabolism, and Reproduction, Quito (Ecuador)); Hopp, M. (Univ. of Witwatersrand, Johannesburg (South Africa)); Rosenbloom, A.; Argente, J. (Univ. of Florida, Gainesville (United States)); Toledo, S.P.A. (Univ. of Sao Paulo (Brazil))

1993-05-01

45

Bioinformatic Analysis of GJB2 Gene Missense Mutations.  

PubMed

Gap junction beta 2 (GJB2) gene is the most commonly mutated connexin gene in patients with autosomal recessive and dominant hearing loss. According to Ensembl (release 74) database, 1347 sequence variations are reported in the GJB2 gene and about 13.5 % of them are categorized as missense SNPs or nonsynonymous variant. Because of the high incidence of GJB2 mutations in hearing loss patients, revealing the molecular effect of GJB2 mutations on protein structure may also provide clear point of view regarding the molecular etiology of deafness. Hence, the aim of this study is to analyze structural and functional consequences of all known GJB2 missense variations to the Cx26 protein by applying multiple bioinformatics methods. Two-hundred and eleven nonsynonymous variants were collected from Ensembl release 74, Leiden Open Variation Database (LOVD) and The Human Gene Mutation Database (HGMD). A number of bioinformatic tools were utilized for predicting the effect of GJB2 missense mutations at the sequence, structural, and functional levels. Some of the mutations were found to locate highly conserved regions and have structural and functional properties. Moreover, GJB2 mutations were also found to affect Cx26 protein at the molecular level via loss or gain of disorder, catalytic site, and post-translational modifications, including methylation, glycosylation, and ubiquitination. Findings, presented here, demonstrated the application of bioinformatic algorithms to predict the effects of mutations causing hearing impairment. I expect, this type of analysis will serve as a start point for future experimental evaluation of the GJB2 gene mutations and it will also be helpful in evaluating other deafness-related gene mutations. PMID:25388846

Yilmaz, Akin

2014-11-12

46

Autosomal Recessive Retinitis Pigmentosa and E150K Mutation in the Opsin Gene*S  

E-print Network

Autosomal Recessive Retinitis Pigmentosa and E150K Mutation in the Opsin Gene*S Received group of hered- itary disorders of the retina caused by mutation in genes of the photoreceptor proteins with an autosomal dominant (adRP), autosomal recessive (arRP), or X-linked pattern of inheritance. Although

Palczewski, Krzysztof

47

MAMMALIAN CELL GENE MUTATION ASSAYS WORKING GROUP REPORT  

EPA Science Inventory

Mammalian cell gene mutation assays have been used for many years and the diversity of the available systems attests to the varied methods found to grow mammalian dells and detect mutations. s part of the International Workshop on Standardization of Genotoxicity Test Procedures, ...

48

EGF receptor gene mutations are common in lung cancers from  

Microsoft Academic Search

Somatic mutations in the tyrosine kinase (TK) domain of the epidermal growth factor receptor (EGFR) gene are reportedly associated with sensitivity of lung cancers to gefitinib (Iressa), kinase inhibitor. In-frame deletions occur in exon 19, whereas point mutations occur frequently in codon 858 (exon 21). We found from sequencing the EGFR TK domain that 7 of 10 gefitinib-sensitive tumors had

William Pao; Vincent Miller; Maureen Zakowski; Jennifer Doherty; Katerina Politi; Inderpal Sarkaria; Bhuvanesh Singh; Robert Heelan; Valerie Rusch; Lucinda Fulton; Elaine Mardis; Doris Kupfer; Richard Wilson; Mark Kris; Harold Varmus

2004-01-01

49

Phenotypic Involvement in Females with the FMR1 Gene Mutation.  

ERIC Educational Resources Information Center

A study investigated phenotypic effects seen in 114 females with premutation and 41 females (ages 18-58) with full Fragile X mental retardation gene mutation. Those with the full mutation had a greater incidence of hand-flapping, eye contact problems, special education help for reading and math, and grade retention. (Author/CR)

Riddle, J. E.; Cheema, A.; Sobesky, W. E.; Gardner, S. C.; Taylor, A. K.; Pennington, B. F.; Hagerman, R. J.

1998-01-01

50

Myoclonic encephalopathy in the CDKL5 gene mutation  

Microsoft Academic Search

ObjectiveEpilepsy with mutation of the CDKL5 gene causes early seizures and is a variant of Rett syndrome (MIM (312750), which is reported typically as infantile spasms. The purpose of this study was to analyze the epileptic histories and EEGs of patients with the CDKL5 mutation.

Sabrina Buoni; Raffaella Zannolli; Vito Colamaria; Francesca Macucci; Rosanna M. di Bartolo; Letizia Corbini; Alessandra Orsi; Michele Zappella; Joseph Hayek

2006-01-01

51

Gene mutations in retinitis pigmentosa and their clinical implications.  

PubMed

Retinitis pigmentosa (RP) is a group of inherited progressive retinal diseases affecting about 1 in 3500 people worldwide. So far, there is no prevention or cure, with permanent visual loss or even blindness the ultimate consequence usually after midlife. The genetics of RP are complex. It can be sporadic, autosomal dominant, autosomal recessive, or X-linked. Thirty-two genes are known to be associated with RP, sometimes the same gene gets involved in different inheritance traits. Some RP cases have a digenic cause. About 60% RP cases still have no known genetic cause. A large number of mutations cause RP, and they can be deletions, insertions, or substitutions that cause missense mutations or truncations. The RHO, RP1, and RPGR genes contribute the greatest number of known mutations causative of RP. But there is no single mutation that alone accounts for more than 10% of unrelated patients. Genetic testing for RP therefore requires screening for a group of genes. High-throughput and automated sequence detection technologies are essential. Due to the complexity in phenotype and genetics, and the fact that RP is untreatable, genetic testing for presymptomatic diagnosis of RP is controversial. Meanwhile, new genes are still to be identified, mostly by family linkage and sib-pair analysis. Research on gene therapy for RP requires information on gene mutations causative of RP. PMID:15563868

Wang, D Y; Chan, W M; Tam, P O S; Baum, L; Lam, D S C; Chong, K K L; Fan, B J; Pang, C P

2005-01-01

52

Mutational and Phylogenetic Analyses of the Mycobacterial mbt Gene Cluster ?§  

PubMed Central

The mycobactin siderophore system is present in many Mycobacterium species, including M. tuberculosis and other clinically relevant mycobacteria. This siderophore system is believed to be utilized by both pathogenic and nonpathogenic mycobacteria for iron acquisition in both in vivo and ex vivo iron-limiting environments, respectively. Several M. tuberculosis genes located in a so-called mbt gene cluster have been predicted to be required for the biosynthesis of the core scaffold of mycobactin based on sequence analysis. A systematic and controlled mutational analysis probing the hypothesized essential nature of each of these genes for mycobactin production has been lacking. The degree of conservation of mbt gene cluster orthologs remains to be investigated as well. In this study, we sought to conclusively establish whether each of nine mbt genes was required for mycobactin production and to examine the conservation of gene clusters orthologous to the M. tuberculosis mbt gene cluster in other bacteria. We report a systematic mutational analysis of the mbt gene cluster ortholog found in Mycobacterium smegmatis. This mutational analysis demonstrates that eight of the nine mbt genes investigated are essential for mycobactin production. Our genome mining and phylogenetic analyses reveal the presence of orthologous mbt gene clusters in several bacterial species. These gene clusters display significant organizational differences originating from an intricate evolutionary path that might have included horizontal gene transfers. Altogether, the findings reported herein advance our understanding of the genetic requirements for the biosynthesis of an important mycobacterial secondary metabolite with relevance to virulence. PMID:21873494

Chavadi, Sivagami Sundaram; Stirrett, Karen L.; Edupuganti, Uthamaphani R.; Vergnolle, Olivia; Sadhanandan, Gigani; Marchiano, Emily; Martin, Che; Qiu, Wei-Gang; Soll, Clifford E.; Quadri, Luis E. N.

2011-01-01

53

A novel PTEN gene promoter mutation and untypical Cowden syndrome  

PubMed Central

Cowden syndrome (CS), an autosomal dominant disorder, is one of a spectrum of clinical disorders that have been linked to germline mutations in the phosphatase and tensin homolog (PTEN) gene. Although 70-80% of patients with CS have an identifiable germline PTEN mutation, the clinical diagnosis presents many challenges because of the phenotypic and genotypic variations. In the present study, we sequenced the exons and the promoter of PTEN gene, mutations and variations in the promoter and exons were identified, and a PTEN protein expression negative region was determined by immunohistochemistry (IHC). In conclusion, a novel promoter mutation we found in PTEN gene may turn off PTEN protein expression occasionally, leading to the disorder of PTEN and untypical CS manifestations. PMID:23825907

Liu, Chen; Li, Guangbing; Chen, Rongrong; Yang, Xiaobo; Zhao, Xue

2013-01-01

54

PFAPA and 12 Common MEFV Gene Mutations Our Clinical Experience  

PubMed Central

Objective: Marshall Syndrome or PFAPA is an inflammatory periodic disease characterized by periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis. Although PFAPA is an auto inflammatory disease, it doesn't have genetic basis such as other periodic fevers. This study evaluates the 12 common MEFV gene mutations in patients with PFAPA syndrome. Methods: 21 patients with PFAPA syndrome who had diagnostic criteria were enrolled in this study and 12 common MEFV gene mutations i.e. P369S, F479L, M680I (G/C), M680I (G/A), I692del, M694V, M694I, K695R, V726A, A744S, R761H, E148Q evaluated. All the patients were screened for MEFV gene mutations by a reverse hybridization assay (FMF Strip Assay, Vienna lab, Vienna, Austria) according to the instructions provided by the manufacturer. Findings : The age of patients was between 6 months to 14 years, and 15 were males. Seven patients had heterozygote and one had compound heterozygote (K695R, V725A) mutation. There were 4 alleles M694V, 3 alleles V726A, 1 allele E148Q and 1 allele K694R. No significant difference existed between mutated patients with non-mutated in symptoms like aphthous and stomatitis, duration of attacks, episodes of fever and response to treatment. Gaslini score test was not helpful to predict the probability of gene mutations. Conclusion: About 30 percent of patients had MEFV gene mutations but these mutations did not play a main role in presentation of PFAPA symptoms.

Salehzadeh, Farhad; Vahedi, Maryam; Hosseini-Asl, Saeid; Jahangiri, Sepideh; Habibzadeh, Shahram; Hosseini-Khotbesara, Mahsa

2014-01-01

55

PTCH Gene Mutations in Odontogenic Keratocysts  

Microsoft Academic Search

An odontogenic keratocyst (OKC) is a benign cystic lesion of the jaws that occurs sporadically or in association with nevoid basal cell carcinoma syndrome (NBCCS). Recently, the gene for NBCCS was cloned and shown to be the human homologue of the Drosophila segment polarity gene Patched (PTCH), a tumor suppressor gene. The PTCH gene encodes a transmembrane protein that acts

D. C. Barreto; R. S. Gomez; A. E. Bale; W. L. Boson; L. De Marco

2000-01-01

56

Somatic cell gene mutations in humans: biomarkers for genotoxicity.  

PubMed Central

Somatic cell gene mutations arising in vivo in humans provide biomarkers for genotoxicity. Four assays, each measuring changes in a different "recorder" gene, are available for detecting mutations of the hemoglobin (Hb) and glycophorin A (gpa) genes in red blood cells and the hypoxanthine-guanine phosphoribosyltransferase (hprt) and HLA genes in T-lymphocytes. Mean adult background mutant frequencies have been established; i.e., approximately 4 x 10(-8) (Hb), 5-10 x 10(-6) (hprt), 10-20 x 10(-6) (gpa) and 30 x 10(-6) (HLA). All the assays have now been used in studies of individuals exposed to physical and/or chemical genotoxic agents, and all have shown elevated values following exposures; examples are presented. In addition to quantitation, the lymphocyte assays allow molecular analyses of in vivo mutations, the definition of background and induced mutational spectra, and the search for unique changes for characterizing specific mutagens. The HPRT system currently has the largest database in this regard. Approximately 15% of adult background hprt mutations are due to gross structural alterations (primarily deletions) having random breakpoints; 85% result from "point" changes detected only by sequencing. In contrast, a specific intragenic deletion due to DNA cleavage at specific sites characterizes fetal hprt mutations, implicating a developmental mistake in their genesis. (This kind of developmental mistake in other genes is frequently observed in lymphoid malignancies.) Mutational spectra are just beginning to be defined for induced hprt mutations, e.g., ionizing radiation produces large deletions.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8143616

Albertini, R J; Nicklas, J A; O'Neill, J P

1993-01-01

57

Adhalin Gene Mutations in Patients with Autosomal Recessive Childhood Onset Muscular Dystrophy with Adhalin Deficiency  

E-print Network

Adhalin Gene Mutations in Patients with Autosomal Recessive Childhood Onset Muscular Dystrophy Neurology, National Sanatorium Tokushima Hospital, Oegun, Tokushima 776, Japan; gLaboratoryof Gene Research Homozygous adhalim gene mutations were found in three patients from two consanguineousfamilies with autosomal

Campbell, Kevin P.

58

Prioritization of neurodevelopmental disease genes by discovery of new mutations.  

PubMed

Advances in genome sequencing technologies have begun to revolutionize neurogenetics, allowing the full spectrum of genetic variation to be better understood in relation to disease. Exome sequencing of hundreds to thousands of samples from patients with autism spectrum disorder, intellectual disability, epilepsy and schizophrenia provides strong evidence of the importance of de novo and gene-disruptive events. There are now several hundred new candidate genes and targeted resequencing technologies that allow screening of dozens of genes in tens of thousands of individuals with high specificity and sensitivity. The decision of which genes to pursue depends on many factors, including recurrence, previous evidence of overlap with pathogenic copy number variants, the position of the mutation in the protein, the mutational burden among healthy individuals and membership of the candidate gene in disease-implicated protein networks. We discuss these emerging criteria for gene prioritization and the potential impact on the field of neuroscience. PMID:24866042

Hoischen, Alexander; Krumm, Niklas; Eichler, Evan E

2014-06-01

59

Mutations in the filaggrin gene and food allergy  

PubMed Central

The results of long-term epidemiological studies show that the number of people suffering from allergic diseases, especially from food allergies and atopic dermatitis (AD), is still increasing. Although the research thus far has been conducted mainly in Europe, North America, and Asia, there are also data appearing from the first studies in that field among the African population. This may indicate the importance of the problem of allergic diseases. The discovery that loss-of-function mutations in the gene coding filaggrin (FLG) are the cause of ichthyosis vulgaris marked a significant breakthrough in understanding the pathogenesis of allergic diseases. The presence of mutations in the filaggrin gene is also an important factor that predisposes to such allergic diseases as: allergic rhinitis, atopic dermatitis, atopic asthma, and food allergy. So far, over 40 loss-of-function mutations and numerous silent mutations in filaggrin have been discovered. PMID:25276250

Markiewicz, Lidia; Wróblewska, Barbara

2014-01-01

60

Novel mutations of the MLC1 gene in Turkish patients.  

PubMed

Megalencephalic Leukoencephalopathy with Subcortical Cysts (MLC) is a rare autosomal recessive disease presenting with increased head circumference at birth or in early infancy. MLC1 (MIM 605908) mutations are responsible for this disorder. In this study, we sequenced the entire coding region of the MLC1 gene in 13 patients and detected five novel nucleotide variations in six of them. Two of the novel variations created a missense amino acid change and the other three were located in the introns and were putative splice mutations. One novel missense variation was observed in two unrelated patients from the central Black Sea region, and the data suggested a founder haplotype for this novel variation. Similarly, three unrelated patients with the previously reported p.Thr118Arg mutation shared a common haplotype. These data suggest an Anatolian origin for these two mutations. As in the previous reports, it is not possible to correlate the clinical phenotype of the patients with the mutation spectra. PMID:21145992

Yüzba?io?lu, Ay?e; Topçu, Meral; Cetin Kocaefe, Y; Ozgüç, Meral

2011-01-01

61

Mediterranean fever gene mutations: correlation with cytotoxic T-lymphocyte-associated antigen 4 gene polymorphism.  

PubMed

Mutations in the Mediterranean fever (MEFV) gene lead to familial Mediterranean fever (FMF), a pro-inflammatory state characterized by outbursts of inflammatory cytokines. The aims of this study were to identify the common mutations of MEFV gene in Egyptian patients with FMF, to study cytotoxic T lymphocyte associated antigen 4 (CTLA-4) gene polymorphism and to evaluate correlations between CTLA4-1661 polymorphisms and MEFV mutations and clinical symptoms. Four hundred and twenty-four patients with clinical pictures suspicious of FMF were enrolled in this study. Mutations in MEFV gene were confirmed by reversed hybridization. Patients with homozygous and compound heterozygous mutations and 120 healthy controls were investigated for polymorphism of -1661 CTLA4 gene and the findings correlated with disease incidence and clinical symptoms of the disease. Ninety-seven patients had single heterozygous mutations and 78 had compound heterozygous or homozygous MEFV gene mutations. M694I/V726A was the most common genotype (14.1%), followed by homozygous M694I. There was no statistically significant difference between patients and controls in incidence of -1661?A/G single nucleotide polymorphism CTLA4 (P?=?0.189), nor any significant correlation with any of the clinical symptoms of FMF and MEFV gene mutations. PMID:25643856

El Hawary, Rabab; Elanwary, Sherif; Meshaal, Safa

2015-03-01

62

Childhood-onset hereditary pancreatitis with mutations in the CT gene and SPINK1 gene.  

PubMed

Hereditary pancreatitis (HP) is an autosomal-dominant gene disorder. The affected genes have been identified as the cationic trypsinogen (CT) gene and the serine protease inhibitor Kazal type 1 (SPINK1) gene. These gene abnormalities alone, however, do not necessarily regulate the onset or severity of pancreatitis, suggesting the involvement of other gene abnormalities and environmental factors. Reported herein is the case of a 9-year-old boy with early-onset HP due to mutations in the CT and SPINK1 genes. The patient had a p.R122H heterozygous mutation in the CT gene and a p.N34S heterozygous mutation in the SPINK1 gene. The father had heterozygous mutation of the SPINK1 gene, and the mother had heterozygous mutation of the CT gene, although neither had a prior history of pancreatitis. In this patient, early onset of HP was attributed to the presence of gene abnormalities in the CT and SPINK1 genes. PMID:24134754

Awano, Hiroyuki; Lee, Tomoko; Yagi, Mariko; Masamune, Atsushi; Kume, Kiyoshi; Takeshima, Yasuhiro; Iijima, Kazumoto

2013-10-01

63

p53 gene mutations in human epithelial skin cancers.  

PubMed

In the present study we analysed 38 epithelial skin cancers, 19 basal cell carcinomas (BCCs), 13 squamous cell carcinomas (SCCs) and six Bowen diseases (BwDs), using a combination of polymerase chain reaction (PCR) and single-stranded conformation polymorphism (SSCP) techniques for the presence of p53 and RAS gene mutations. Whereas 48% (9/19) of the BCCs tested presented a mutated p53 gene, the frequency was lower (15%, 2/13) in our series of SCCs and negative in the BwDs. Nine of the 11 characterized mutations were single-nucleotide substitutions and, interestingly, seven of these involved CC dimers, where a C was changed into a T or a G (three C-->T transitions and four C-->G transversions). This mutational pattern, added to the fact that all the mutated tumors occurred at sun-exposed body sites, implicates UV light in their genesis. Furthermore, we observed two internal deletions of 6 and 24 bp whose flanking sequences contained two or three Cs on either strand. In addition to molecular detection, we searched for p53 protein accumulation, by immunocytochemical staining, in a subset of 23 epithelial skin tumors (nine bearing a mutation, 14 which scored negative in our assay). Three commercially available anti-p53 antibodies (PAb CM1, mAbs DO7 and 1801) were used, and 3/23 (all showing a mutated p53 gene) presented specific nuclear staining. In contrast to other reported data we could not detect any activating RAS gene mutation in our series of human skin cancers. PMID:8437842

Molčs, J P; Moyret, C; Guillot, B; Jeanteur, P; Guilhou, J J; Theillet, C; Basset-Sčguin, N

1993-03-01

64

Frequent ras gene mutations in squamous cell cervical cancer  

Microsoft Academic Search

Eighty samples of cervical invasive squamous cell carcinoma were examined for ras gene mutations using polymerase chain reaction (PCR) followed by restriction enzyme digestion. We found 28 (35%) cervical cancers contained ras mutations at H-ras codon 12, 49 (61%) at K-ras codon 12, and 5 (6%) at K-ras codon 13. There were no significant differences in incidence of the ras

Y. F. Wong; Tony K. H. Chung; T. H. Cheung; S. K. Lam; Y. G. Xu; Allan M. Z. Chang

1995-01-01

65

Risk of Pancreatitis with Mutation of the Cystic Fibrosis Gene  

Microsoft Academic Search

BACKGROUND:Between 5% and 15% of patients with recurrent pancreatitis have no identified etiology after routine investigation and advanced endoscopic evaluation.OBJECTIVE:To determine whether mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene is a risk factor for idiopathic pancreatitis.METHODS:We compared the frequency of CFTR mutations as measured by DNA probe analysis in a case group of persons with idiopathic pancreatitis

C. P. Choudari; Thomas F. Imperiale; Stuart Sherman; Evan Fogel; Glen A. Lehman

2004-01-01

66

Gene mutations and molecularly targeted therapies in acute myeloid leukemia  

PubMed Central

Acute myelogenous leukemia (AML) can progress quickly and without treatment can become fatal in a short period of time. However, over the last 30 years fine-tuning of therapeutics have increased the rates of remission and cure. Cytogenetics and mutational gene profiling, combined with the option of allogeneic hematopoietic stem cell transplantation offered in selected patients have further optimized AML treatment on a risk stratification basis in younger adults. However there is still an unmet medical need for effective therapies in AML since disease relapses in almost half of adult patients becoming refractory to salvage therapy. Improvements in the understanding of molecular biology of cancer and identification of recurrent mutations in AML provide opportunities to develop targeted therapies and improve the clinical outcome. In the spectrum of identified gene mutations, primarily targetable lesions are gain of function mutations of tyrosine kinases FLT3, JAK2 and cKIT for which specific, dual and multi-targeted small molecule inhibitors have been developed. A number of targeted compounds such as sorafenib, quizartinib, lestaurtinib, midostaurin, pacritinib, PLX3397 and CCT137690 are in clinical development. For loss-of-function gene mutations, which are mostly biomarkers of favorable prognosis, combined therapeutic approaches can maximize the therapeutic efficacy of conventional therapy. Apart from mutated gene products, proteins aberrantly overexpressed in AML appear to be clinically significant therapeutic targets. Such a molecule for which targeted inhibitors are currently in clinical development is PLK1. We review characteristic gene mutations, discuss their biological functions and clinical significance and present small molecule compounds in clinical development, which are expected to have a role in treating AML subtypes with characteristic molecular alterations. PMID:23358589

Hatzimichael, Eleftheria; Georgiou, Georgios; Benetatos, Leonidas; Briasoulis, Evangelos

2013-01-01

67

Prevalence of haemochromatosis gene mutations in Parkinson's disease  

PubMed Central

The aim of this study was to investigate a possible association between haemochromatosis (HFE) gene mutations and the prevalence of Parkinson's disease. The HFE gene encodes a protein that modulates iron absorption. Several studies have documented increased iron levels in the basal ganglia in patients with Parkinson's disease. In a study on patients with concurrent hereditary haemochromatosis and Parkinson's disease, abnormal deposition of iron in the basal ganglia was suggested as an inductor of Parkinson's disease. In this study, genotype frequencies of the HFE mutations C282Y, H63D and S65C were estimated in 388 patients with Parkinson's disease and compared with frequencies found in comparable studies. No significant differences were found in frequencies between the patients and comparable populations. This study does not indicate increased susceptibility to Parkinson's disease in HFE gene mutation carriers in Norway. PMID:17056630

Aamodt, Anne Hege; Stovner, Lars Jacob; Thorstensen, Ketil; Lydersen, Stian; White, Linda R; Aasly, Jan O

2007-01-01

68

Frequent mutations in chromatin-remodeling genes in pulmonary carcinoids  

PubMed Central

Pulmonary carcinoids are rare neuroendocrine tumors of the lung. The molecular alterations underlying the pathogenesis of these tumors have not been systematically studied so far. Here we perform gene copy number analysis (n=54), genome/exome (n=44) and transcriptome (n=69) sequencing of pulmonary carcinoids and observe frequent mutations in chromatin-remodeling genes. Covalent histone modifiers and subunits of the SWI/SNF complex are mutated in 40% and 22.2% of the cases respectively, with MEN1, PSIP1 and ARID1A being recurrently affected. In contrast to small-cell lung cancer and large-cell neuroendocrine tumors, TP53 and RB1 mutations are rare events, suggesting that pulmonary carcinoids are not early progenitor lesions of the highly aggressive lung neuroendocrine tumors but arise through independent cellular mechanisms. These data also suggest that inactivation of chromatin remodeling genes is sufficient to drive transformation in pulmonary carcinoids. PMID:24670920

Lu, Xin; Sun, Ruping; Ozreti?, Luka; Seidal, Danila; Zander, Thomas; Leenders, Frauke; George, Julie; Müller, Christian; Dahmen, Ilona; Pinther, Berit; Bosco, Graziella; Konrad, Kathryn; Altmüller, Janine; Nürnberg, Peter; Achter, Viktor; Lang, Ulrich; Schneider, Peter M; Bogus, Magdalena; Soltermann, Alex; Brustugun, Odd Terje; Helland, Ĺslaug; Solberg, Steinar; Lund-Iversen, Marius; Ansén, Sascha; Stoelben, Erich; Wright, Gavin M.; Russell, Prudence; Wainer, Zoe; Solomon, Benjamin; Field, John K; Hyde, Russell; Davies, Michael PA.; Heukamp, Lukas C; Petersen, Iver; Perner, Sven; Lovly, Christine; Cappuzzo, Federico; Travis, William D; Wolf, Jürgen; Vingron, Martin; Brambilla, Elisabeth; Haas, Stefan A.; Buettner, Reinhard; Thomas, Roman K

2014-01-01

69

Reduced Rates of Gene Loss, Gene Silencing, and Gene Mutation in Dnmt1Deficient Embryonic Stem Cells  

Microsoft Academic Search

Tumor suppressor gene inactivation is a crucial event in oncogenesis. Gene inactivation mechanisms include events resulting in loss of heterozygosity (LOH), gene mutation, and transcriptional silencing. The contribu- tion of each of these different pathways varies among tumor suppressor genes and by cancer type. The factors that influence the relative utilization of gene inactivation pathways are poorly understood. In this

MATILDA F. CHAN; RENEE VAN AMERONGEN; TARLOCHAN NIJJAR; EDWIN CUPPEN; PETER A. JONES; PETER W. LAIRD

2001-01-01

70

Altered Chromosomal Positioning, Compaction, and Gene Expression with a Lamin A/C Gene Mutation  

PubMed Central

Background Lamins A and C, encoded by the LMNA gene, are filamentous proteins that form the core scaffold of the nuclear lamina. Dominant LMNA gene mutations cause multiple human diseases including cardiac and skeletal myopathies. The nuclear lamina is thought to regulate gene expression by its direct interaction with chromatin. LMNA gene mutations may mediate disease by disrupting normal gene expression. Methods/Findings To investigate the hypothesis that mutant lamin A/C changes the lamina's ability to interact with chromatin, we studied gene misexpression resulting from the cardiomyopathic LMNA E161K mutation and correlated this with changes in chromosome positioning. We identified clusters of misexpressed genes and examined the nuclear positioning of two such genomic clusters, each harboring genes relevant to striated muscle disease including LMO7 and MBNL2. Both gene clusters were found to be more centrally positioned in LMNA-mutant nuclei. Additionally, these loci were less compacted. In LMNA mutant heart and fibroblasts, we found that chromosome 13 had a disproportionately high fraction of misexpressed genes. Using three-dimensional fluorescence in situ hybridization we found that the entire territory of chromosome 13 was displaced towards the center of the nucleus in LMNA mutant fibroblasts. Additional cardiomyopathic LMNA gene mutations were also shown to have abnormal positioning of chromosome 13, although in the opposite direction. Conclusions These data support a model in which LMNA mutations perturb the intranuclear positioning and compaction of chromosomal domains and provide a mechanism by which gene expression may be altered. PMID:21179469

Abuisneineh, Fida; Fahrenbach, John P.; Zhang, Yuan; MacLeod, Heather; Dellefave, Lisa; Pytel, Peter; Selig, Sara; Labno, Christine M.; Reddy, Karen; Singh, Harinder; McNally, Elizabeth

2010-01-01

71

Molecular Evolution, Mutation Size and Gene Pleiotropy: A Geometric Reexamination  

PubMed Central

The influence of phenotypic effects of genetic mutations on molecular evolution is not well understood. Neutral and nearly neutral theories of molecular evolution predict a negative relationship between the evolutionary rate of proteins and their functional importance; nevertheless empirical studies seeking relationships between evolutionary rate and the phenotypic role of proteins have not produced conclusive results. In particular, previous studies have not found the expected negative correlation between evolutionary rate and gene pleiotropy. Here, we studied the effect of gene pleiotropy and the phenotypic size of mutations on the evolutionary rate of genes in a geometrical model, in which gene pleiotropy was characterized by n molecular phenotypes that affect organismal fitness. For a nearly neutral process, we found a negative relationship between evolutionary rate and mutation size but pleiotropy did not affect the evolutionary rate. Further, for a selection model, where most of the substitutions were fixed by natural selection in a randomly fluctuating environment, we also found a negative relationship between evolutionary rate and mutation size, but interestingly, gene pleiotropy increased the evolutionary rate as \\documentclass[10pt]{article} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{pmc} \\usepackage[Euler]{upgreek} \\pagestyle{empty} \\oddsidemargin -1.0in \\begin{document} \\begin{equation*}\\sqrt{n}\\end{equation*}\\end{document}. These findings may explain part of the disagreement between empirical data and traditional expectations. PMID:21196522

Razeto-Barry, Pablo; Díaz, Javier; Cotoras, Darko; Vásquez, Rodrigo A.

2011-01-01

72

Novel ?eta (?)-Thalassemia Mutation in Turkish Children.  

PubMed

Beta (?)-thalassemia is the most frequently observed hereditary blood disorder in the world. It is characterized by deficiency of hemoglobin ?-globin gene and is also a profoundly heterogeneous both at the molecular and clinical level. In the case of ?-thalassemia, there is reduced (?(+) type) or absent (?(o) type) synthesis of the beta chains of hemoglobin. ?-Thalassemia clinically occurs in three main forms: major, intermedia and minor according to requirement of transfusion. The objective of this study was to evaluate ?-thalassemia mutations in 89 patients ranging from 2 months to 16 years of age, who enrolled to Medical School Research and Training Hospital, Gaziantep University. The direct DNA sequence analysis was performed for mutation scanning of ?-globin gene. 89 children with ?-Thalassemia including all types were analyzed, 16 different ?-thalassemia mutations were detected. We have also identified a novel mutation (HBB.c.-80delT, rs397509430) in the promoter region (-30 TATA box) of ?-globin gene, and clinical data of patient having novel mutation was given. The ?-Thalassemia mutations were determined as ?-Thalassemia major type in 42 patients (47.19 %), ?-Thalassemia intermedia in 4 (4.49 %), ?-Thalassemia minor in 43, (48.31 %) patients. The most frequent mutation was IVS I-110 G>A, followed by IVS I-1 G>A, IVS I-6 T>C, IVS II-1 G>A, respectively. PMID:25825561

Ulasli, Mustafa; Oztuzcu, Serdar; Kirkbes, Sevil; Bay, Ali; Igci, Yusuf Ziya; Bayraktar, Recep; Igci, Mehri; Ergun, Sercan; Cakmak, Ecir Ali; Aytekin, Elif; Arslan, Ahmet

2015-06-01

73

Mutator gene and hereditary non-polyposis colorectal cancer  

DOEpatents

The human MSH2 gene, responsible for hereditary non-polyposis colorectal cancer, was identified by virtue of its homology to the MutS class of genes, which are involved in DNA mismatch repair. The sequence of cDNA clones of the human gene are provided, and the sequence of the gene can be used to demonstrate the existence of germ line mutations in hereditary non-polyposis colorectal cancer (HNPCC) kindreds, as well as in replication error.sup.+ (RER.sup.+) tumor cells.

de la Chapelle, Albert (Helsingfors, FI); Vogelstein, Bert (Baltimore, MD); Kinzler, Kenneth W. (Baltimore, MD)

2008-02-05

74

Analysis of the [lambda] S? gene function by mutational suppressors  

E-print Network

are tolerant to colicin K. Another gene, the rex gene is responsible for the exclusion of phage T4rII (figure 1A) . This activity is not seen in a tolB background. Lysis in a tolB lysogen can occur in the absence of a functional S gene. Presumably...ANALYSIS OF THE 1 S GENE FUNCTION BY MUTATIONAL SUPPRESSORS A Thesis by CHARLES DAVID SOHASKEY Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE...

Sohaskey, Charles David

1992-01-01

75

Gene Mutations Gene a finite segment of DNA specified  

E-print Network

mutation to be expressed. · Over 500 recessive diseases have been identified. · These include sickle cell of that age and sex. #12;Mammalian Cell Culture Studies · Mammalian cell cultures were stressed by absence

Massey, Thomas N.

76

Mutational analysis of X-linked adrenoleukodystrophy gene  

Microsoft Academic Search

X-linked adrenoleukodystrophy (ALD) is an inherited peroxisomal disorder characterized by progressive neurological dysfunction,\\u000a occasionally associated with adrenal insufficiency. The clinical thenotypes of ALD are quite variable, and include childhood\\u000a ALD, adult-onset ALD, adrenomyeloneuropathy, and Addison's disease only. Although the causative gene for ALD has been identified,\\u000a the physiological role of the gene product remains to be clarified. Despite many mutations

Hiroki Takano; Ryoko Koike; Osamu Onodera; Shoji Tsuji

2000-01-01

77

DCEG Scientists Identify New Gene Mutation Related to Familial Melanoma  

Cancer.gov

Scientists have identified a rare inherited mutation in a gene that can increase the risk of familial melanoma, according to a study that appeared online in Nature Genetics on March 30, 2014. Although the finding does not offer immediate benefit to patients, variation in the Protection of Telomeres-1 (POT1) gene provides additional clues as to the origins of melanoma and may open new avenues in prevention and treatment research. Read the full NCI Benchmarks blog post about this study.

78

PTPN11 gene mutations: linking the Gln510Glu mutation to the “LEOPARD syndrome phenotype”  

Microsoft Academic Search

We describe the “LEOPARD syndrome (LS) phenotype” associated with the Gln510Glu mutation of the PTPN11 gene in two patients presenting with rapidly progressive severe biventricular obstructive hypertrophic cardiomyopathy and structural abnormalities of the mitral valve, facial anomalies, café-au-lait spots and multiple lentigines.

M. Cristina Digilio; Anna Sarkozy; Giuseppe Pacileo; Giuseppe Limongelli; Bruno Marino; Bruno Dallapiccola

2006-01-01

79

Mutations in the deubiquitinase gene USP8 cause Cushing's disease.  

PubMed

Cushing's disease is caused by corticotroph adenomas of the pituitary. To explore the molecular mechanisms of endocrine autonomy in these tumors, we performed exome sequencing of 10 corticotroph adenomas. We found somatic mutations in the USP8 deubiquitinase gene in 4 of 10 adenomas. The mutations clustered in the 14-3-3 protein binding motif and enhanced the proteolytic cleavage and catalytic activity of USP8. Cleavage of USP8 led to increased deubiqutination of the EGF receptor, impairing its downregulation and sustaining EGF signaling. USP8 mutants enhanced promoter activity of the gene encoding proopiomelanocortin. In summary, our data show that dominant mutations in USP8 cause Cushing's disease via activation of EGF receptor signaling. PMID:25485838

Reincke, Martin; Sbiera, Silviu; Hayakawa, Akira; Theodoropoulou, Marily; Osswald, Andrea; Beuschlein, Felix; Meitinger, Thomas; Mizuno-Yamasaki, Emi; Kawaguchi, Kohei; Saeki, Yasushi; Tanaka, Keiji; Wieland, Thomas; Graf, Elisabeth; Saeger, Wolfgang; Ronchi, Cristina L; Allolio, Bruno; Buchfelder, Michael; Strom, Tim M; Fassnacht, Martin; Komada, Masayuki

2015-01-01

80

Identification of Constrained Cancer Driver Genes Based on Mutation Timing  

PubMed Central

Cancer drivers are genomic alterations that provide cells containing them with a selective advantage over their local competitors, whereas neutral passengers do not change the somatic fitness of cells. Cancer-driving mutations are usually discriminated from passenger mutations by their higher degree of recurrence in tumor samples. However, there is increasing evidence that many additional driver mutations may exist that occur at very low frequencies among tumors. This observation has prompted alternative methods for driver detection, including finding groups of mutually exclusive mutations and incorporating prior biological knowledge about gene function or network structure. Dependencies among drivers due to epistatic interactions can also result in low mutation frequencies, but this effect has been ignored in driver detection so far. Here, we present a new computational approach for identifying genomic alterations that occur at low frequencies because they depend on other events. Unlike passengers, these constrained mutations display punctuated patterns of occurrence in time. We test this driver–passenger discrimination approach based on mutation timing in extensive simulation studies, and we apply it to cross-sectional copy number alteration (CNA) data from ovarian cancer, CNA and single-nucleotide variant (SNV) data from breast tumors and SNV data from colorectal cancer. Among the top ranked predicted drivers, we find low-frequency genes that have already been shown to be involved in carcinogenesis, as well as many new candidate drivers. The mutation timing approach is orthogonal and complementary to existing driver prediction methods. It will help identifying from cancer genome data the alterations that drive tumor progression. PMID:25569148

Sakoparnig, Thomas; Fried, Patrick; Beerenwinkel, Niko

2015-01-01

81

Mutation screening in candidate genes in four Chinese brachydactyly families.  

PubMed

Autosomal dominant brachydactyly (BD) is a skeletal disorder with several subtypes, including brachydactyly type A1 (BDA1) and brachydactyly type B1 (BDB1). Mutations in Indian hedgehog (IHH) are usually associated with BDA1, whereas heterozygous mutations in receptor tyrosine kinase-like orphan receptor 2 (ROR2) are mainly responsible for BDB1. On the basis of the clinical phenotype identification, we screened IHH and ROR2 by the candidate gene approach using PCR direct sequencing. We found three known mutations of IHH (c.283_285delGAG, p.E95del; c.298 G>A, p.D100N; c.300C>G, p.D100E) in three Chinese families with BDA1, and a novel heterozygous nonsense mutation of ROR2 (c.2273C>A, p.S758X) in a BDB1 family. It was noted that c.300C>G mutation was a new nucleotide substitution compared to the reported c.300C>A, which led to the same amino acid change (p.D100E). The novel nonsense mutation p.S758X was verified by absence in the unaffected family members and the 100 randomly-selected controls. In this paper, we report three recurrent mutations with a new nucleotide substitution of IHH in three Chinese families with BDA1 and a novel nonsense mutation in BDB1 pedigree. We therefore recommend the approach of candidate gene screening as the first choice for genetic testing for BD. PMID:25696018

Dong, Sufang; Wang, Yinghui; Tao, Shengxiang; Zheng, Fang

2015-01-01

82

Discovery of induced point mutations in maize genes by TILLING  

Microsoft Academic Search

BACKGROUND: Going from a gene sequence to its function in the context of a whole organism requires a strategy for targeting mutations, referred to as reverse genetics. Reverse genetics is highly desirable in the modern genomics era; however, the most powerful methods are generally restricted to a few model organisms. Previously, we introduced a reverse-genetic strategy with the potential for

Bradley J Till; Steven H Reynolds; Clifford Weil; Nathan Springer; Chris Burtner; Kim Young; Elisabeth Bowers; Christine A Codomo; Linda C Enns; Anthony R Odden; Elizabeth A Greene; Luca Comai; Steven Henikoff

2004-01-01

83

International team identifies critical genes mutated in stomach cancer  

Cancer.gov

An international team of scientists, led by researchers from the Duke-NUS Graduate Medical School in Singapore and National Cancer Centre of Singapore, has identified hundreds of novel genes that are mutated in stomach cancer, the second-most lethal cancer worldwide.

84

Prevalence of ras gene mutations in human colorectal cancers  

Microsoft Academic Search

The Department of Medical Biochemistry and t Department of Organic Chemistry, State University of Leiden, Sylvius Laboratories, The Netherlands * The Oncology Center and t Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA A combination of DNA hybridization analyses and tissue sectioning techniques demonstrate that ras gene mutations occur in over a third of

Johannes L. Bos; Eric R. Fearon; Matty Verlaan-De Vries; Jacques H. van Boom; Alex J. van der Eb; Bert Vogelstein

1987-01-01

85

Mutations of the tyrosinase gene produce autosomal recessive ocular albinism  

SciTech Connect

Albinism has historically been divided into ocular (OA) and oculocutaneous (OCA) types based on the presence or absence of clinically apparent skin and hair involvement in an individual with the ocular features of albinism. The major genes for OCA include the tyrosinase gene in OCA1 and the P gene in OCA2. X-linked and autosomal recessive OA have been described and the responsible genes have not been identified. We now present six Caucasian individuals who have the phenotype of autosomal recessive OA but who have OCA1 as shown by the presence of mutations of the tyrosinase. They had white or very light hair and white skin at birth, and cutaneous pigment developed in the first decade of life. At ages ranging from 1.5-23 years, hair color was dark blond to light brown. The skin had generalized pigment and well developed tan was present on the exposed arm and face skin of four. Iris pigment was present and iris translucency varied. Molecular analysis of the tyrosinase gene, using PCR amplification and direct di-deoxy sequencing showed the following mutations: E398Z/E398Q, P406S/g346a, R402E/T373K, ?/D383N, and H211N/T373K. The homozygous individual was not from a known consanguineous mating. T373K is the most common tyrosinase gene mutation in our laboratory. Three of these mutations are associated with a total loss of tyrosinase activity (g346a splice-site, T373K, and D383N), while four are associated with residual enzyme activity (H211N, R402E, E398Q, and P406S). These studies show that mutations of the tyrosinase gene can produce the phenotype of autosomal recessive OA in an individual who has normal amounts of cutaneous pigment and the ability to tan after birth. This extends the phenotypic range of OCA1 to normal cutaneous pigment after early childhood, and suggest that mutations of the tyrosinase gene account for a significant number of individuals with autosomal recessive OA.

King, R.A.; Summers, C.G.; Oetting, W.S. [Univ. of Minnesota, Minneapolis, MN (United States)] [and others

1994-09-01

86

Strategies to Achieve Conditional Gene Mutation in Mice  

PubMed Central

The laboratory mouse is an ideal model organism for studying disease because it is physiologically similar to human and also because its genome is readily manipulated. Genetic engineering allows researchers to introduce specific loss-of-function or gain-of-function mutations into genes and then to study the resulting phenotypes in an in vivo context. One drawback of using traditional transgenic and knockout mice to study human diseases is that many mutations passed through the germline can profoundly affect development, thus impeding the study of disease phenotypes in adults. New technology has made it possible to generate conditional mutations that can be introduced in a spatially and/or temporally restricted manner. Mouse strains carrying conditional mutations represent valuable experimental models for the study of human diseases and they can be used to develop strategies for prevention and treatment of these diseases. In this article, we will describe the most widely used DNA recombinase systems used to achieve conditional gene mutation in mouse models and discuss how these systems can be employed in vivo. PMID:24692485

Gierut, Jessica J.; Jacks, Tyler E.; Haigis, Kevin M.

2014-01-01

87

Strategies to achieve conditional gene mutation in mice.  

PubMed

The laboratory mouse is an ideal model organism for studying disease because it is physiologically similar to human and also because its genome is readily manipulated. Genetic engineering allows researchers to introduce specific loss-of-function or gain-of-function mutations into genes and then to study the resulting phenotypes in an in vivo context. One drawback of using traditional transgenic and knockout mice to study human diseases is that many mutations passed through the germline can profoundly affect development, thus impeding the study of disease phenotypes in adults. New technology has made it possible to generate conditional mutations that can be introduced in a spatially and/or temporally restricted manner. Mouse strains carrying conditional mutations represent valuable experimental models for the study of human diseases and they can be used to develop strategies for prevention and treatment of these diseases. In this article, we will describe the most widely used DNA recombinase systems used to achieve conditional gene mutation in mouse models and discuss how these systems can be employed in vivo. PMID:24692485

Gierut, Jessica J; Jacks, Tyler E; Haigis, Kevin M

2014-04-01

88

PDCD10 Gene Mutations in Multiple Cerebral Cavernous Malformations  

PubMed Central

Cerebral cavernous malformations (CCMs) are vascular abnormalities that may cause seizures, intracerebral haemorrhages, and focal neurological deficits. Familial form shows an autosomal dominant pattern of inheritance with incomplete penetrance and variable clinical expression. Three genes have been identified causing familial CCM: KRIT1/CCM1, MGC4607/CCM2, and PDCD10/CCM3. Aim of this study is to report additional PDCD10/CCM3 families poorly described so far which account for 10-15% of hereditary cerebral cavernous malformations. Our group investigated 87 consecutive Italian affected individuals (i.e. positive Magnetic Resonance Imaging) with multiple/familial CCM through direct sequencing and Multiplex Ligation-Dependent Probe Amplification (MLPA) analysis. We identified mutations in over 97.7% of cases, and PDCD10/CCM3 accounts for 13.1%. PDCD10/CCM3 molecular screening revealed four already known mutations and four novel ones. The mutated patients show an earlier onset of clinical manifestations as compared to CCM1/CCM2 mutated patients. The study of further families carrying mutations in PDCD10/CCM3 may help define a possible correlation between genotype and phenotype; an accurate clinical follow up of the subjects would help define more precisely whether mutations in PDCD10/CCM3 lead to a characteristic phenotype. PMID:25354366

Cigoli, Maria Sole; Avemaria, Francesca; De Benedetti, Stefano; Gesu, Giovanni P.; Accorsi, Lucio Giordano; Parmigiani, Stefano; Corona, Maria Franca; Capra, Valeria; Mosca, Andrea; Giovannini, Simona; Notturno, Francesca; Ciccocioppo, Fausta; Volpi, Lilia; Estienne, Margherita; De Michele, Giuseppe; Antenora, Antonella; Bilo, Leda; Tavoni, Antonietta; Zamponi, Nelia; Alfei, Enrico; Baranello, Giovanni; Riva, Daria; Penco, Silvana

2014-01-01

89

Mutational characterization of ATP7B gene in 103 Wilson's disease patients from Southern China: identification of three novel mutations.  

PubMed

Wilson's disease (WD) is an autosomal recessive inheritance disorder of copper metabolism due to mutations in the ATP7B gene. The distribution of ATP7B gene mutations is diverse in different population. This study aimed to examine the genotypes of the ATP7B mutant alleles in WD patients from Southern China. Genomic DNA was extracted from 103 WD patients and 60 healthy patients. Mutations were screened and detected by DNA sequencing. A total of 51 different ATP7B mutations were identified in WD patients, including six homozygous, 51 compound heterozygous, and 39 single heterozygotes. Three mutations were found to be novel, including one missense mutation (c.2549C>T) and two frameshift mutations (c.3851_3876del and c.1057delC). The most frequent mutations are Arg778Leu (18.93%), Ile1148Thr (8.74%), and Pro992Leu (4.37%). Different from the published results of early studies, Ile1148Thr was found to be the second common mutation in our cohort. The highest mutation detection rate was on exon 8 (43.69%), followed by exon 16 (24.27%), and exon 12 (17.48%). The total mutation detection rate on exon 8, 12, and 16 was 85.44%. No ATP7B gene mutation was found in healthy patients. In conclusion, we identified three novel mutations and Ile1148Thr as another hotspot mutation in WD patients from Southern China. Most of the mutations can be detected by screening exon 8, 12, and 16. Our research has further enriched the mutation spectrum of the ATP7B gene in Chinese and may help to develop genetic screening strategies of WD. PMID:25089800

Wei, Zhisheng; Huang, Yeqing; Liu, Aiqun; Diao, Shengpeng; Yu, Qingyun; Peng, Zhongxing; Hong, Mingfan

2014-10-01

90

Mutation analysis of the MECP2 gene in patients of Slavic origin with Rett syndrome: novel mutations and polymorphisms  

Microsoft Academic Search

Rett syndrome (RTT), an X-linked dominant neurodevelopmental disorder in females, is caused mainly by de novo mutations in\\u000a the methyl-CpG-binding protein 2 gene (MECP2). Here we report mutation analysis of the MECP2 gene in 87 patients with RTT from the Czech and Slovak Republics, and Ukraine. The patients, all girls, with classical RTT\\u000a were investigated for mutations using bi-directional DNA

Daniela Zahorakova; Robert Rosipal; Jan Hadac; Alena Zumrova; Vladimir Bzduch; Nadezda Misovicova; Alice Baxova; Jiri Zeman; Pavel Martasek

2007-01-01

91

Mutations of epigenetic regulatory genes are common in thymic carcinomas  

PubMed Central

Genetic alterations and etiology of thymic epithelial tumors (TETs) are largely unknown, hampering the development of effective targeted therapies for patients with TETs. Here TETs of advanced-stage patients enrolled in a clinical trial of molecularly-guided targeted therapies were employed for targeted sequencing of 197 cancer-associated genes. Comparative sequence analysis of 78?TET/blood paired samples obtained from 47 thymic carcinoma (TC) and 31 thymoma patients revealed a total of 86 somatic non-synonymous sequence variations across 39 different genes in 33 (42%) TETs. TCs (62%; 29/47) showed higher incidence of somatic non-synonymous mutations than thymomas (13%; 4/31; p < 0.0001). TP53 was the most frequently mutated gene in TETs (n = 13; 17%), especially in TCs (26%), and was associated with a poorer overall survival (p < 0.0001). Genes in histone modification [BAP1 (n = 6; 13%), SETD2 (n = 5; 11%), ASXL1 (n = 2; 4%)], chromatin remodeling [SMARCA4 (n = 2; 4%)], and DNA methylation [DNMT3A (n = 3; 7%), TET2 (n = 2; 4%), WT1 (n = 2; 4%)] pathways were recurrently mutated in TCs, but not in thymomas. Our results suggest a potential disruption of epigenetic homeostasis in TCs, and a substantial difference in genetic makeup between TCs and thymomas. Further investigation is warranted into the roles of epigenetic dysregulation in TC development and its potential for targeted therapy. PMID:25482724

Wang, Yisong; Thomas, Anish; Lau, Christopher; Rajan, Arun; Zhu, Yuelin; Killian, J. Keith; Petrini, Iacopo; Pham, Trung; Morrow, Betsy; Zhong, Xiaogang; Meltzer, Paul S.; Giaccone, Giuseppe

2014-01-01

92

Endemic polycythemia in Russia: mutation in the VHL gene.  

PubMed

Chuvash polycythemia (CP) is an autosomal recessive condition that is endemic in the Russian mid-Volga River region of Chuvashia. We previously found that CP patients may have increased serum erythropoietin (EPO) levels, ruled out linkage to both the EPO and EPO receptor (EPOR) gene loci, and hypothesized that the defect may lie in the oxygen homeostasis pathway. We now report a study of five multiplex Chuvash families which confirms that CP is associated with significant elevations of serum EPO levels and rules out a location for the CP gene on chromosome 11 as had been reported by other investigators or a mutation of the HIF-1 alpha gene. Using a genome-wide screen, we localized a region on chromosome 3 with a LOD score >2. After sequencing three candidate genes, we identified a C to T transition at nucleotide 598 (an R200W mutation) in the von Hippel-Lindau (VHL) gene. The VHL protein (pVHL) downregulates the alpha subunit of hypoxia-inducible factor 1 (HIF-1 alpha), the main regulator of hypoxia adaptation, by targeting the protein for degradation. In the simplest scenario, disruption of pVHL function causes a failure to degrade HIF-1 alpha resulting in accumulation of HIF-1 alpha, upregulation of downstream target genes such as EPO, and the clinical manifestation of polycythemia. These findings strongly suggest that CP is a congenital disorder of oxygen homeostasis. PMID:11987242

Ang, Sonny O; Chen, Hua; Gordeuk, Victor R; Sergueeva, Adelina I; Polyakova, Lydia A; Miasnikova, Galina Y; Kralovics, Robert; Stockton, David W; Prchal, Josef T

2002-01-01

93

Molecular screening of pituitary adenomas for gene mutations and rearrangements  

SciTech Connect

Although pituitary tumors arise as benign monoclonal neoplasms, genetic alterations have not readily been identified in these adenomas. The authors studied restriction fragment abnormalities involving the GH gene locus, and mutations in the p53 and H-, K-, and N-ras genes in 22 human GH cell adenomas. Twenty two nonsecretory adenomas were also examined for p53 and ras gene mutations. Seven prolactinoma DNA samples were tested for deletions in the multiple endocrine neoplasia-1 (MEN-1) locus, as well as for rearrangements in the hst gene, a member of the fibroblast growth factor family. In DNA from GH-cell adenomas, identical GH restriction patterns were detected in both pituitary and lymphocyte DNA in all patients and in one patient with a mixed GH-TSH cell adenoma. Using polymerase chain reaction (PCR)-single stranded conformation polymorphism analysis, no mutations were detected in exons 5, 6, 7 and 8 of the p53 gene in GH cell adenomas nor in 22 nonsecretory adenomas. Codons 12/13 and 61 of H-ras, K-ras, and N-ras genes were also intact on GH cell adenomas and in nonsecretory adenomas. Site-specific probes for chromosome 11q13 including, PYGM, D11S146, and INT2 were used in 7 sporadic PRL-secreting adenomas to detect deletions of the MEN-1 locus on chromosome 11. One patient was identified with a loss of 11p, and the remaining 6 patients did not demonstrate loss of heterozygosity in the pituitary 11q13 locus, compared to lymphocyte DNA. None of these patients demonstrated hst gene rearrangements which also maps to this locus. These results show that p53 and ras gene mutations are not common events in the pathogenesis of acromegaly and nonsecretory tumors. Although hst gene rearrangements and deletions of 11q13 are not associated with sporadic PRl-cell adenoma formation, a single patient was detected with a partial loss of chromosome 11, including the putative MEN-1 site. 31 refs., 5 figs., 2 tabs.

Herman, V.; Drazin, N.Z.; Gonskey, R.; Melmed, S. (Cedars-Sinai Medical Center, Los Angeles, CA (United States))

1993-07-01

94

Mutational Analysis of Angiogenin Gene in Parkinson's Disease  

PubMed Central

Mutations in the angiogenic factor, angiogenin (ANG), have been identified in patients with both familial and sporadic amyotrophic lateral sclerosis (ALS) and are thought to have a neuroprotective function. Parkinsonism has been noted in kindreds with ANG mutations and variants in the ANG gene have been found to associate with PD in two Caucasian populations. We therefore hypothesized that mutations in ANG may also contribute to idiopathic Parkinson's disease (PD). We sequenced ANG gene in a total of 1498 participants comprising 750 PD patients and 748 age/gender matched controls from Taiwan. We identified one novel synonymous substitution, c.C100T (p.L10L), in a single heterozygous state in one PD patient, which was not observed in controls. The clinical phenotypes and [99mTc]-TORDAT-SPECT images of the p.L10L carrier were similar to that seen in idiopathic PD. In addition, we also identified one common variant, c.T330G (p.G110G, rs11701), which was previously reported to associate with PD risk in Caucasians. However, the frequency of TG/GG genotype was comparable between PD cases and controls (odds ratio: 0.85, 95% confidence interval: 0.29–2.55, P?=?0.78). Our results did not support that ANG rs11701 variant is a genetic risk factor for PD in our population. We conclude that mutations in ANG are not a common cause for idiopathic PD. PMID:25386690

Chen, Meng-Ling; Wu, Ruey-Meei; Tai, Chun-Hwei; Lin, Chin-Hsien

2014-01-01

95

Mutations in BTD gene causing biotinidase deficiency: a regional report.  

PubMed

Biotinidase deficiency is an autosomal recessive inborn error of biotin metabolism. Children with biotinidase deficiency cannot cleave biocytin and, therefore, cannot recycle biotin. Untreated individuals become secondarily biotin deficient, which in turn results in decreased activities of the biotin-dependent carboxylases and the subsequent accumulation of toxic metabolites causing clinical symptoms. Biotinidase deficiency is characterized by neurological, cutaneous manifestations and metabolic abnormalities. The worldwide incidence of profound biotinidase deficiency has been estimated at 1:112,271. The human biotinidase gene is located on chromosome 3p25 and consists of four exons with a total length of 1629 base pairs. To date, more than 100 mutations in the biotinidase gene known to cause biotinidase deficiency have been reported. The vast majority of mutations are homozygous or compound heterozygous. Finding known mutations can be correlated with the biochemical enzymatic results. This report summarizes the demographic features of patients identified as biotinidase deficient from August of 2012 through August of 2013 and mutation analysis results for 20 cases in the southeast region of Turkey. PMID:25423671

Kasapkara, Çi?dem Seher; Akar, Melek; Özbek, Mehmet Nuri; Tüzün, Heybet; Aldudak, Bedri; Baran, R?za Taner; Tanyalç?n, Tijen

2015-03-01

96

Mutations in Genes Encoding Essential Mitotic Functions in DROSOPHILA MELANOGASTER  

PubMed Central

Temperature-sensitive mutations at 15 loci that affect the fidelity of mitotic chromosome behavior have been isolated in Drosophila melanogaster . These mitotic mutants were detected in a collection of 168 EMS-induced X-linked temperature-sensitive (ts) lethal and semilethal mutants. Our screen for mutations with mitotic effects was based upon the reasoning that under semirestrictive conditions such mutations could cause an elevated frequency of mitotic chromosome misbehavior and that such events would be detectable with somatic cell genetic techniques. Males hemizygous for each ts lethal and heterozygous for the recessive autosomal cell marker mwh were reared under semirestrictive conditions, and the wings of those individuals surviving to adulthood were examined for an increased frequency of mwh clones. Those mutations producing elevated levels of chromosome instability during growth of the wing imaginal disc were also examined for their effects on chromosome behavior in the cell lineages producing the abdominal cuticle. Fifteen mutations affect chromosome behavior in both wing and abdominal cells and thus identify loci generally required for the fidelity of mitotic chromosome transmission. Mapping and complementation tests show that these mutations represent 15 loci. One mutant is an allele of a locus (mus-101) previously identified by mutagensensitive mutants and a second mutant is an allele of the lethal locus zw10.—The 15 mutants were also examined cytologically for their effects on chromosomes in larval neuroblasts. Taken together, the results of our cytological and genetical studies show that these mutants identify loci with wild-type functions necessary for either (1) maintenance of chromosome integrity or (2) regular disjunction of chromosomes or (3) chromosome condensation. Thus, these mutations define a broad spectrum of genes required for the normal execution of the mitotic chromosome cycle. PMID:3928429

Smith, David A.; Baker, Bruce S.; Gatti, Maurizio

1985-01-01

97

BSE Case Associated with Prion Protein Gene Mutation  

Microsoft Academic Search

Bovine spongiform encephalopathy (BSE) is a transmissible spongiform encephalopathy (TSE) of cattle and was first detected in 1986 in the United Kingdom. It is the most likely cause of variant Creutzfeldt-Jakob disease (CJD) in humans. The origin of BSE remains an enigma. Here we report an H-type BSE case associated with the novel mutation E211K within the prion protein gene

Jürgen A. Richt; S. Mark Hall

2008-01-01

98

Human lysozyme gene mutations cause hereditary systemic amyloidosis  

Microsoft Academic Search

HEREDITARY non-neuropathic systemic amyloidosis (Ostertag-type)1 is a rare autosomal dominant disease in which amyloid deposition in the viscera is usually fatal by the fifth decade. In some families it is caused by mutations in the apolipoprotein AI gene2,3 but in two unrelated English families under our care the amyloid deposits did not contain apoAI, despite a report that this may

M. B. Pepys; P. N. Hawkins; D. R. Booth; D. M. Vigushin; G. A. Tennent; A. K. Soutar; N. Totty; O. Nguyen; C. C. F. Blake; C. J. Terry; T. G. Feest; A. M. Zalin; J. J. Hsuan

1993-01-01

99

Inherited Mutations in Breast Cancer Genes—Risk and Response  

Microsoft Academic Search

Germ-line mutations in BRCA1 and BRCA2 confer a high risk of developing breast cancer. They account, however, for only 40% of strongly familial breast cancer cases.\\u000a Intensive genome-wide searches for other highly-penetrant BRCA genes that, individually account for a sizeable fraction of the remaining heritability has not identified any plausible candidates.\\u000a The “missing heritability” is thought to be due to

Andrew Y. Shuen; William D. Foulkes

2011-01-01

100

Mutations in the Pericentrin (PCNT) Gene Cause Primordial Dwarfism  

Microsoft Academic Search

Fundamental processes influencing human growth can be revealed by studying extreme short stature. Using genetic linkage analysis, we find that biallelic loss-of-function mutations in the centrosomal pericentrin (PCNT) gene on chromosome 21q22.3 cause microcephalic osteodysplastic primordial dwarfism type II (MOPD II) in 25 patients. Adults with this rare inherited condition have an average height of 100 centimeters and a brain

Anita Rauch; Christian T. Thiel; Detlev Schindler; Ursula Wick; Yanick J. Crow; Arif B. Ekici; Anthonie J. van Essen; Timm O. Goecke; Lihadh Al-Gazali; Krystyna H. Chrzanowska; Christiane Zweier; Han G. Brunner; Kristin Becker; Cynthia J. Curry; Bruno Dallapiccola; Koenraad Devriendt; Arnd Dörfler; Esther Kinning; André Megarbane; Peter Meinecke; Robert K. Semple; Stephanie Spranger; Annick Toutain; Richard C. Trembath; Egbert Voss; Louise Wilson; Raoul Hennekam; Francis de Zegher; Helmuth-Günther Dörr; André Reis

2008-01-01

101

Optimization of gene sequences under constant mutational pressure and selection  

NASA Astrophysics Data System (ADS)

We have analyzed the influence of constant mutational pressure and selection on the nucleotide composition of DNA sequences of various size, which were represented by the genes of the Borrelia burgdorferi genome. With the help of MC simulations we have found that longer DNA sequences accumulate much less base substitutions per sequence length than short sequences. This leads us to the conclusion that the accuracy of replication may determine the size of genome.

Kowalczuk, M.; Gierlik, A.; Mackiewicz, P.; Cebrat, S.; Dudek, M. R.

1999-12-01

102

Mutation spectrum and splicing variants in the OPA1 gene  

Microsoft Academic Search

Optic atrophy type 1 (OPA1, MIM 165500) is a dominantly inherited optic neuropathy that features low visual acuity leading in many cases to legal blindness. We have recently shown, with others, that mutations in the OPA1 gene encoding a dynamin-related mitochondrial protein, underlie the dominant form of optic atrophy. Here we report that OPA1 has eight mRNA isoforms as a

Cécile Delettre; Jean-Michel Griffoin; Josseline Kaplan; Hélčne Dollfus; Birgit Lorenz; Laurence Faivre; Guy Lenaers; Pascale Belenguer; Christian P. Hamel

2001-01-01

103

Combining gene mutation with gene expression data improves outcome prediction in myelodysplastic syndromes.  

PubMed

Cancer is a genetic disease, but two patients rarely have identical genotypes. Similarly, patients differ in their clinicopathological parameters, but how genotypic and phenotypic heterogeneity are interconnected is not well understood. Here we build statistical models to disentangle the effect of 12 recurrently mutated genes and 4 cytogenetic alterations on gene expression, diagnostic clinical variables and outcome in 124 patients with myelodysplastic syndromes. Overall, one or more genetic lesions correlate with expression levels of ~20% of all genes, explaining 20-65% of observed expression variability. Differential expression patterns vary between mutations and reflect the underlying biology, such as aberrant polycomb repression for ASXL1 and EZH2 mutations or perturbed gene dosage for copy-number changes. In predicting survival, genomic, transcriptomic and diagnostic clinical variables all have utility, with the largest contribution from the transcriptome. Similar observations are made on the TCGA acute myeloid leukaemia cohort, confirming the general trends reported here. PMID:25574665

Gerstung, Moritz; Pellagatti, Andrea; Malcovati, Luca; Giagounidis, Aristoteles; Porta, Matteo G Della; Jädersten, Martin; Dolatshad, Hamid; Verma, Amit; Cross, Nicholas C P; Vyas, Paresh; Killick, Sally; Hellström-Lindberg, Eva; Cazzola, Mario; Papaemmanuil, Elli; Campbell, Peter J; Boultwood, Jacqueline

2015-01-01

104

Combining gene mutation with gene expression data improves outcome prediction in myelodysplastic syndromes  

PubMed Central

Cancer is a genetic disease, but two patients rarely have identical genotypes. Similarly, patients differ in their clinicopathological parameters, but how genotypic and phenotypic heterogeneity are interconnected is not well understood. Here we build statistical models to disentangle the effect of 12 recurrently mutated genes and 4 cytogenetic alterations on gene expression, diagnostic clinical variables and outcome in 124 patients with myelodysplastic syndromes. Overall, one or more genetic lesions correlate with expression levels of ~20% of all genes, explaining 20–65% of observed expression variability. Differential expression patterns vary between mutations and reflect the underlying biology, such as aberrant polycomb repression for ASXL1 and EZH2 mutations or perturbed gene dosage for copy-number changes. In predicting survival, genomic, transcriptomic and diagnostic clinical variables all have utility, with the largest contribution from the transcriptome. Similar observations are made on the TCGA acute myeloid leukaemia cohort, confirming the general trends reported here. PMID:25574665

Gerstung, Moritz; Pellagatti, Andrea; Malcovati, Luca; Giagounidis, Aristoteles; Porta, Matteo G Della; Jädersten, Martin; Dolatshad, Hamid; Verma, Amit; Cross, Nicholas C. P.; Vyas, Paresh; Killick, Sally; Hellström-Lindberg, Eva; Cazzola, Mario; Papaemmanuil, Elli; Campbell, Peter J.; Boultwood, Jacqueline

2015-01-01

105

Analysis of gene mutations among South Indian patients with maple syrup urine disease: identification of four novel mutations.  

PubMed

Maple syrup urine disease (MSUD) is predominantly caused by mutations in the BCKDHA, BCKDHB and DBT genes, which encode for the E1alpha, E1beta and E2 subunits of the branched-chain alpha-keto acid dehydrogenase complex, respectively. Because disease causing mutations play a major role in the development of the disease, prenatal diagnosis at gestational level may have significance in making decisions by parents. Thus, this study was aimed to screen South Indian MSUD patients for mutations and assess the genotype-phenotype correlation. Thirteen patients diagnosed with MSUD by conventional biochemical screening such as urine analysis by DNPH test, thin layer chromatography for amino acids and blood amino acid quantification by HPLC were selected for mutation analysis. The entire coding regions of the BCKDHA, BCKDHB and DBT genes were analyzed for mutations by PCR-based direct DNA sequencing. BCKDHA and BCKDHB mutations were seen in 43% of the total ten patients, while disease-causing DBT gene mutation was observed only in 14%. Three patients displayed no mutations. Novel mutations were c.130C>T in BCKDHA gene, c. 599C>T and c.121_122delAC in BCKDHB gene and c.190G>A in DBT gene. Notably, patients harbouring these mutations were non-responsive to thiamine supplementation and other treatment regimens and might have a worse prognosis as compared to the patients not having such mutations. Thus, identification of these mutations may have a crucial role in the treatment as well as understanding the molecular mechanisms in MSUD. PMID:24772966

Narayanan, M P; Menon, Krishnakumar N; Vasudevan, D M

2013-10-01

106

Gene Augmentation for adRP Mutations in RHO  

PubMed Central

Mutations in the gene for rhodopsin, RHO, cause autosomal dominant retinitis pigmentosa, a disease characterized by death of rod photoreceptor cells. At the end stage, when most rods are gone, cones die too, taking central vision with them. One goal of gene therapy, therefore, is to preserve central vision by promoting rod survival in the vicinity of the macula. Dominance in RHO mutations is associated with two phenomena: interference with the function of normal rhodopsin and intrinsic toxicity of the mutant protein. In the case of interference, increased production of the wild-type protein may be therapeutic, but in the case of toxicity, suppression of the mutant protein may also be needed. RHO augmentation has made use of advances in gene delivery to the retina using adeno-associated virus (AAV). Several strategies have been developed for suppression of rhodopsin expression, but because of the heterogeneity of RHO mutations they are not specific for the mutant allele: They suppress both mutant and wild-type RHO. Experiments in autosomal dominant retinitis pigmentosa (adRP) mouse models suggest that both RHO augmentation and supplementation plus suppression preserve the survival of rod cells. PMID:25037104

Lewin, Alfred S.; Rossmiller, Brian; Mao, Haoyu

2014-01-01

107

Myostatin gene mutated mice induced with tale nucleases.  

PubMed

Myostain gene (MSTN) is expressed primarily in skeletal muscle, and negatively regulates skeletal muscle mass; it has been suggested that mice with MSTN inhibition have reduced adiposity and improved insulin sensitivity. Therefore, it is important to establish a fast and effective gene editing method. In this report, we established the myostatin mutated-mouse model by microinjection of Transcription Activator-Like Effector Nucleases (TALENs) mRNA within the mouse fertilized oocytes and achieved high rates of mutagenesis of the mouse MSTN in C57BL/6J. Six of 45 born mice carried target mutations and we appointed one as the parental mating with wild mouse to produce the F1 and backcross to produce the F2 generation. All the mutations of the mice were examined quickly and efficiently by high-resolution melting curve analysis (HRMA) and then verified by direct sequencing. We obtained the homozygous of the F2 generation which transmitted the mutant alleles to the progeny with 100% efficiency. Mutant mice exhibited increases in muscle mass comparable to those observed in wild-type mice. Therefore, combining TALEN-mediated gene targeting with HRMA technology is a superior method of constructing genetically modified mice through microinjection in the mouse fertilized oocytes with high efficiency and short time of selection. PMID:25695746

Zhou, Fangfang; Sun, Ruilin; Chen, Hongyan; Fei, Jian; Lu, Daru

2015-07-01

108

The DCC gene: Structural analysis and mutations in colorectal carcinomas  

SciTech Connect

DCC is a candidate tumor-suppressor gene encoding a protein with sequence similarity to cell adhesion molecules such as N-CAM. A set of overlapping YAC clones that contains the entire DCC coding region was isolated. Studies of this YAC contig showed that the DCC gene spans approximately 1.4 Mb. For elucidation of exon-intron structure, lambda phage clones containing all known coding sequences were isolated from a genomic library. These clones were used to demonstrate the existence of 29 DCC exons, and the sequences of the exon-intron boundaries were determined for each. Twenty-three polymorphic markers from chromosome 18 were then studied in a panel of primary colorectal tumors that had lost some, but not all, of chromosome 18. In most of these tumors, the region that was lost included DCC. Finally, Southern blot and PCR-based approaches were used to search for subtle mutations in several DCC exons. One tumor that had a point mutation in exon 28 was found, resulting in a proline to histidine substitution. A second tumor with a point mutation in intron 13 was also found. The regional map and genomic structure of DCC should provide the means to more extensively study DCC gene alterations and protein function in normal and neoplastic cells. 23 refs., 4 figs., 1 tab.

Cho, K.R.; Oliner, J.D.; Simons, J.W.; Hedrick, L.; Preisinger, A.C.; Vogelstein, B. (John Hopkins School of Medicine, Baltimore, MD (United States)); Fearon, E.R. (Yale Univ. School of Medicine, New Haven, CT (United States)); Hedge, P. (Zeneca Pharmaceuticals, Macclesfield (United Kingdom)); Silverman, G.A. (Harvard Medical School, Boston, MA (United States))

1994-02-01

109

Validation of high-resolution DNA melting analysis for mutation scanning of the CDKL5 gene: identification of novel mutations.  

PubMed

Mutations in the cyclin-dependent kinase-like 5 gene (CDKL5) have been predominantly described in epileptic encephalopathies of female, including infantile spasms with Rett-like features. Up to now, detection of mutations in this gene was made by laborious, expensive and/or time consuming methods. Here, we decided to validate high-resolution melting analysis (HRMA) for mutation scanning of the CDKL5 gene. Firstly, using a large DNA bank consisting to 34 samples carrying different mutations and polymorphisms, we validated our analytical conditions to analyse the different exons and flanking intronic sequences of the CDKL5 gene by HRMA. Secondly, we screened CDKL5 by both HRMA and denaturing high performance liquid chromatography (dHPLC) in a cohort of 135 patients with early-onset seizures. Our results showed that point mutations and small insertions and deletions can be reliably detected by HRMA. Compared to dHPLC, HRMA profiles are more discriminated, thereby decreasing unnecessary sequencing. In this study, we identified eleven novel sequence variations including four pathogenic mutations (2.96% prevalence). HRMA appears cost-effective, easy to set up, highly sensitive, non-toxic and rapid for mutation screening, ideally suited for large genes with heterogeneous mutations located along the whole coding sequence, such as the CDKL5 gene. PMID:23064044

Raymond, Laure; Diebold, Bertrand; Leroux, Céline; Maurey, Hélčne; Drouin-Garraud, Valérie; Delahaye, Andre; Dulac, Olivier; Metreau, Julia; Melikishvili, Gia; Toutain, Annick; Rivier, François; Bahi-Buisson, Nadia; Bienvenu, Thierry

2013-01-01

110

Somatic mutations in the BRCA1 gene in Chinese sporadic breast and ovarian cancer  

Microsoft Academic Search

Inherited mutations in the BRCA1 gene confer increased susceptibility to breast and ovarian cancer. Its role in sporadic carcinogenesis is not well defined. Somatic mutations in breast cancers have not been reported and to date there are only three reports of somatic mutations in sporadic ovarian cancers. To investigate the contribution of BRCA1 mutations to sporadic breast and ovarian cancer

Ui-Soon Khoo; Hilmi Ozcelik; Annie NY Cheung; Louis WC Chow; Hextan YS Ngan; Susan J Done; A C T Liang; Vivian WY Chan; Gordon KH Au; Wing-Fung Ng; Yuet-Foon Leung; Florence Loong; Philip Ip; Gavin SW Chan; Irene L Andrulis; Jing Lu; Faith CS Ho

1999-01-01

111

Mutations in the cystic fibrosis gene in men with congenital bilateral absence of the vas deferens  

Microsoft Academic Search

This paper reviews the relationship between mutations in the cystic fibrosis (CF) gene (CFTR mutations) and congenital bilateral absence of the vas deferens (CBAVD). Two CFTR mutations were identified in 14.5% of the 449 men with CBAVD thus far reported in the literature while one CFTR mutation was found in another 48.1%. CBAVD appears to be a heterogeneous genetic condition,

Marc De Braekeleer; Claude Férec

1996-01-01

112

Mutational analysis of genes coding for cell surface proteins in colorectal cancer cell lines reveal novel altered pathways, druggable mutations and mutated epitopes for targeted therapy  

PubMed Central

We carried out a mutational analysis of 3,594 genes coding for cell surface proteins (Surfaceome) in 23 colorectal cancer cell lines, searching for new altered pathways, druggable mutations and mutated epitopes for targeted therapy in colorectal cancer. A total of 3,944 somatic non-synonymous substitutions and 595 InDels, occurring in 2,061 (57%) Surfaceome genes were catalogued. We identified 48 genes not previously described as mutated in colorectal tumors in the TCGA database, including genes that are mutated and expressed in >10% of the cell lines (SEMA4C, FGFRL1, PKD1, FAM38A, WDR81, TMEM136, SLC36A1, SLC26A6, IGFLR1). Analysis of these genes uncovered important roles for FGF and SEMA4 signaling in colorectal cancer with possible therapeutic implications. We also found that cell lines express on average 11 druggable mutations, including frequent mutations (>20%) in the receptor tyrosine kinases AXL and EPHA2, which have not been previously considered as potential targets for colorectal cancer. Finally, we identified 82 cell surface mutated epitopes, however expression of only 30% of these epitopes was detected in our cell lines. Notwithstanding, 92% of these epitopes were expressed in cell lines with the mutator phenotype, opening new venues for the use of “general” immune checkpoint drugs in this subset of patients. PMID:25193853

Correa, Bruna R.; Bettoni, Fabiana; Koyama, Fernanda C.; Navarro, Fabio C.P.; Perez, Rodrigo O.; Mariadason, John; Sieber, Oliver M.; Strausberg, Robert L.; Simpson, Andrew J.G.; Jardim, Denis L.F.; Reis, Luiz Fernando L.; Parmigiani, Raphael B.; Galante, Pedro A.F.; Camargo, Anamaria A.

2014-01-01

113

RAS gene mutations in acute and chronic myelocytic leukemias, chronic myeloproliferative disorders, and myelodysplastic syndromes  

Microsoft Academic Search

The authors report on investigations aimed at detecting mutated RAS genes in a variety of preleukemic disorders and leukemias of myeloid origin. DNA transfection analyses (tumorigenicity assay) and hybridization to mutation-specific oligonucleotide probes established NRAS mutations in codon 12 or 61 of 4\\/9 acute myelocytic leukemias (AML) and three AML lines. Leukemic cells of another AML patient showed HRAS gene

J. W. G. Janssen; A. C. M. Steenvoorden; J. Lyons; B. Anger; J. U. Boehlke; J. L. Bos; H. Seliger; C. R. Bartram

1987-01-01

114

Free-Radical-Induced Mutation vs Redox Regulation: Costs and Benefits of Genes in Organelles  

E-print Network

Focus Free-Radical-Induced Mutation vs Redox Regulation: Costs and Benefits of Genes in Organelles of movement of genes to the nucleus is decreased mutation: plastids and mitochondria have high volume-specific rates of re- dox reactions, producing oxygen free radicals that chemically modify DNA. These mutations

Allen, John F.

115

TP53 gene mutations of lung cancer patients in upper northern Thailand and environmental risk factors  

E-print Network

TP53 gene mutations of lung cancer patients in upper northern Thailand and environmental risk mutations are observed in about 40e70% of lung cancer tissues, and the hot spot codon mu- tations factors that influence TP53 gene mutation in lung cancer patients residing areas with high lung cancer

116

Identification of factor VIII gene mutations and carrier detection in Korean haemophilia A patients  

Microsoft Academic Search

Haemophilia A is an X-linked bleeding disorder caused by heterogeneous mutations in the factor VIII gene. More than 900 mutations within the FVIII coding and untranslated regions have been identified. The most common defects is an inversion in the FVIII gene that accounts for nearly 40-50% of individuals with severe haemophilia A. Point mutations, deletions and insertions are responsible for

J.-Y. HAN; J.-N. LEE; S.-Y. LEE; I.-J. KIM; C.-M KIM

2007-01-01

117

Mutations of the cystic fibrosis gene locus within the population of the Northwest of England  

Microsoft Academic Search

A large group of patients with cystic fibrosis (CF) from the Northwest of England were analysed for mutations within the CF gene. Eleven separate mutations were identified comprising 91.5% of the responsible genes. Molecular confirmation of a CF diagnosis becomes possible in 84% of cases. Only 1.19% of cases negative for the nine mutations have CF. The results of molecular

M. Super; M. J. Schwarz

1992-01-01

118

Inherited mutations in breast cancer genes--risk and response.  

PubMed

Germ-line mutations in BRCA1 and BRCA2 confer a high risk of developing breast cancer. They account, however, for only 40% of strongly familial breast cancer cases. Intensive genome-wide searches for other highly-penetrant BRCA genes that, individually account for a sizeable fraction of the remaining heritability has not identified any plausible candidates. The "missing heritability" is thought to be due to cumulative effects of susceptibility alleles associated with low to moderate penetrance, in accordance with a polygenic model of inheritance. In addition, a large number of individually very rare, highly penetrant variants could account for part of the gap. Meanwhile, an understanding of the function of BRCA1 and BRCA2 in the DNA damage response pathway has lead to the identification of a number of breast cancer susceptibility genes including PALB2, CHEK2, ATM and BRIP1, all of which interact directly or indirectly with BRCA1 or BRCA2. Knowledge of how BRCA1 and BRCA2 maintain genomic integrity has also led the development of novel targeted therapies. Here we summarize the recent advances made in the understanding of the functions of these two genes, as well as the risks and responses associated with mutations in these and other breast cancer susceptibility genes. PMID:21461995

Shuen, Andrew Y; Foulkes, William D

2011-04-01

119

Mutations of p53 gene exons 4-8 in human esophageal cancer  

PubMed Central

AIM: To characterize the tumor suppressor gene p53 mutations in exon 4, esophageal cancer and adjacent non-cancerous tissues. METHODS: We performed p53 (exons 4-8) gene mutation analysis on 24 surgically resected human esophageal cancer specimens by PCR, single-strand conformation polymorphism, and DNA sequencing. RESULTS: p53 gene mutations were detected in 9 of 22 (40.9%) esophageal cancer specimens and 10 of 17 (58.8%) adjacent non-cancerous tissues. Eight of sixteen (50.0%) point mutations detected were G–A transitions and 9 of 18 (50.0%) p53 gene mutations occurred in exon 4 in esophageal cancer specimens. Only 1 of 11 mutations detected was G-A transition and 4 of 11 (36.4%) p53 gene mutations occurred in exon 4 in adjacent non-cancerous tissues. CONCLUSION: Mutation of p53 gene in exon 4 may play an important role in development of esophageal cancer. The observation of p53 gene mutation in adjacent non-cancerous tissues suggests that p53 gene mutation may be an early event in esophageal carcinogenesis. Some clinical factors, including age, sex, pre-operation therapy and location of tumors, do not influence p53 gene mutation rates. PMID:15902745

Li, Li-Ya; Tang, Jin-Tian; Jia, Li-Qun; Li, Pei-Wen

2005-01-01

120

Mutations in the K+/Cl- cotransporter gene kazachoc (kcc) increase seizure susceptibility in Drosophila  

E-print Network

CG9925 gene was responsible for the strain’s recessive BSrecessive lethal phenotypes, indicating that kcc is an essential gene.recessive eas PC80 allele carries a frameshift mutation and probably constitutes a null allele. The bss gene

Hekmat-Scafe, Daria S; Lundy, Miriam Y; Ranga, Rakhee; Tanouye, Mark A

2006-01-01

121

Progranulin gene mutation with an unusual clinical and neuropathologic presentation.  

PubMed

Progranulin gene (PGRN) mutations cause frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). Patients usually present with a frontotemporal dementia syndrome and have prominent atrophy and neuronal loss in frontal and temporal cortices and the striatum, with neuronal intranuclear and cytoplasmic inclusions. Clinical, neuropathological, and genetic studies are reported on an individual with PGRN mutation and her family members. We describe a patient with a PGRN c.26C>A mutation who presented with progressive stuttering dysarthria, oculomotor abnormalities, choreic buccolingual movements, and mild parkinsonism. Two other family members were affected, one with a behavioral variant frontotemporal dementia syndrome, the other with a diagnosis of probable Alzheimer's disease. At autopsy there was no neuronal loss in the cortex or medial temporal lobe structures, but there was striatal gliosis. Immunohistochemistry for ubiquitin and TDP-43 revealed neuronal cytoplasmic and intranuclear inclusions as well as neurites. This study further expands the clinical and pathological spectrum of PGRN mutations, and suggests the diagnosis could be missed in some individuals with atypical presentations. PMID:18442119

Wider, Christian; Uitti, Ryan J; Wszolek, Zbigniew K; Fang, John Y; Josephs, Keith A; Baker, Matthew C; Rademakers, Rosa; Hutton, Michael L; Dickson, Dennis W

2008-06-15

122

Identification of mutated core cancer modules by integrating somatic mutation, copy number variation, and gene expression data  

PubMed Central

Motivation Understanding the molecular mechanisms underlying cancer is an important step for the effective diagnosis and treatment of cancer patients. With the huge volume of data from the large-scale cancer genomics projects, an open challenge is to distinguish driver mutations, pathways, and gene sets (or core modules) that contribute to cancer formation and progression from random passengers which accumulate in somatic cells but do not contribute to tumorigenesis. Due to mutational heterogeneity, current analyses are often restricted to known pathways and functional modules for enrichment of somatic mutations. Therefore, discovery of new pathways and functional modules is a pressing need. Results In this study, we propose a novel method to identify Mutated Core Modules in Cancer (iMCMC) without any prior information other than cancer genomic data from patients with tumors. This is a network-based approach in which three kinds of data are integrated: somatic mutations, copy number variations (CNVs), and gene expressions. Firstly, the first two datasets are merged to obtain a mutation matrix, based on which a weighted mutation network is constructed where the vertex weight corresponds to gene coverage and the edge weight corresponds to the mutual exclusivity between gene pairs. Similarly, a weighted expression network is generated from the expression matrix where the vertex and edge weights correspond to the influence of a gene mutation on other genes and the Pearson correlation of gene mutation-correlated expressions, respectively. Then an integrative network is obtained by further combining these two networks, and the most coherent subnetworks are identified by using an optimization model. Finally, we obtained the core modules for tumors by filtering with significance and exclusivity tests. We applied iMCMC to the Cancer Genome Atlas (TCGA) glioblastoma multiforme (GBM) and ovarian carcinoma data, and identified several mutated core modules, some of which are involved in known pathways. Most of the implicated genes are oncogenes or tumor suppressors previously reported to be related to carcinogenesis. As a comparison, we also performed iMCMC on two of the three kinds of data, i.e., the datasets combining somatic mutations with CNVs and secondly the datasets combining somatic mutations with gene expressions. The results indicate that gene expressions or CNVs indeed provide extra useful information to the original data for the identification of core modules in cancer. Conclusions This study demonstrates the utility of our iMCMC by integrating multiple data sources to identify mutated core modules in cancer. In addition to presenting a generally applicable methodology, our findings provide several candidate pathways or core modules recurrently perturbed in GBM or ovarian carcinoma for further studies. PMID:24565034

2013-01-01

123

Mutations and a polymorphism in the tuberin gene  

SciTech Connect

Two deletions and a polymorphism have been identified in the recently described tuberin gene. The tuberin gene (designated TSC2) when mutated causes tuberous sclerosis complex (TSC). Fifty-three affected individuals (30 from families with multiple affected and 23 isolated cases) were screened with the tuberin cDNA for gross deletions or rearrangements. Both deletions were found in families with multiple affected members (family designations: HOU-5 and HOU-22). The approximate size of the deletion in HOU-5 is ten kilobases and eliminates a BamHI restriction site. The deletion includes a portion of the 5{prime} half of the tuberin cDNA. The deletion in HOU-22 occurs in the 3{prime} half of the gene. The deletions are being further characterized. A HindIII restriction site polymorphism was detected by a 0.5 kilobase probe from the 5{prime} coding region of the tuberin gene in an individual from a family linked to chromosome 9 (posterior probability of linkage 93%). The polymorphism did not segregate with TSC in the family. The family had previously been shown to give negative results with multiple markers on chromosome 16. The polymorphism was also seen in one individual among a panel of 20 randomly selected unaffected individuals. Thirty-five additional affected probands (five from families and 30 isolated cases) are being tested with the tuberin cDNA. Testing for subtle mutations is our panel of 80 affected probands is underway utilizing SSCP. Additional mutations or polymorphisms detected will be reported. The tuberin cDNA was a kind gift of The European Chromosome 16 Tuberous Sclerosis Consortium.

Northup, H.; Rodriguez, J.A.; Au, K.S.; Rodriguez, E. [Univ. of Texas Medical School, Houston, TX (United States)

1994-09-01

124

Molecular Basis of Human CD36 Gene Mutations  

PubMed Central

CD36 is a transmembrane glycoprotein of the class B scavenger receptor family. The CD36 gene is located on chromosome 7 q11.2 and is encoded by 15 exons. Defective CD36 is a likely candidate gene for impaired fatty acid metabolism, glucose intolerance, atherosclerosis, arterial hypertension, diabetes, cardiomyopathy, Alzheimer disease, and modification of the clinical course of malaria. Contradictory data concerning the effects of antiatherosclerotic drugs on CD36 expression indicate that further investigation of the role of CD36 in the development of atherosclerosis may be important for the prevention and treatment of this disease. This review summarizes current knowledge of CD36 gene structure, splicing, and mutations and the molecular, metabolic, and clinical consequences of these phenomena. PMID:17673938

Ra?, Monika Ewa; Safranow, Krzysztof; Poncyljusz, Wojciech

2007-01-01

125

Identification of fifteen novel PHEX gene mutations in Finnish patients with hypophosphatemic rickets.  

PubMed

We have carried out a mutation screening of the PHEX gene in Finnish patients with hypophosphatemia. A total of 100% (5/5) of the familial HYP patients (X-linked hypophosphatemia) and 93% (14/15) of the sporadic cases were found to carry a mutation in the PHEX gene. We identified 18 mutations, of which 15 were novel. We report also a new polymorphism 46bp upstream of exon 16. Two families were segregating the same nonsense mutation in exon 1 (R20X), but since this mutation has been previously reported in three independent studies, we consider it to be a mutational hotspot rather than a Finnish founder mutation. We did not find PHEX gene mutations in two additional hypophosphatemia families in which the mode of inheritance was other than X-linked dominant. Also, no mutation could be detected in a patient with suspected oncogenic osteomalacia (OHO). PMID:10737991

Tyynismaa, H; Kaitila, I; Näntö-Salonen, K; Ala-Houhala, M; Alitalo, T

2000-04-01

126

U Penn researchers classify gene mutations in a children's cancer that may point to improved treatments  

Cancer.gov

Oncology researchers studying gene mutations in the childhood cancer neuroblastoma are refining their diagnostic tools to predict which patients are more likely to respond to drugs called ALK inhibitors that target such mutations.

127

Optimal control of gene mutation in DNA replication.  

PubMed

We propose a molecular-level control system view of the gene mutations in DNA replication from the finite field concept. By treating DNA sequences as state variables, chemical mutagens and radiation as control inputs, one cell cycle as a step increment, and the measurements of the resulting DNA sequence as outputs, we derive system equations for both deterministic and stochastic discrete-time, finite-state systems of different scales. Defining the cost function as a summation of the costs of applying mutagens and the off-trajectory penalty, we solve the deterministic and stochastic optimal control problems by dynamic programming algorithm. In addition, given that the system is completely controllable, we find that the global optimum of both base-to-base and codon-to-codon deterministic mutations can always be achieved within a finite number of steps. PMID:22454557

Yu, Juanyi; Li, Jr-Shin; Tarn, Tzyh-Jong

2012-01-01

128

Optimal Control of Gene Mutation in DNA Replication  

PubMed Central

We propose a molecular-level control system view of the gene mutations in DNA replication from the finite field concept. By treating DNA sequences as state variables, chemical mutagens and radiation as control inputs, one cell cycle as a step increment, and the measurements of the resulting DNA sequence as outputs, we derive system equations for both deterministic and stochastic discrete-time, finite-state systems of different scales. Defining the cost function as a summation of the costs of applying mutagens and the off-trajectory penalty, we solve the deterministic and stochastic optimal control problems by dynamic programming algorithm. In addition, given that the system is completely controllable, we find that the global optimum of both base-to-base and codon-to-codon deterministic mutations can always be achieved within a finite number of steps. PMID:22454557

Yu, Juanyi; Li, Jr-Shin; Tarn, Tzyh-Jong

2012-01-01

129

Cohesin gene mutations in tumorigenesis: from discovery to clinical significance  

PubMed Central

Cohesin is a multi-protein complex composed of four core subunits (SMC1A, SMC3, RAD21, and either STAG1 or STAG2) that is responsible for the cohesion of sister chromatids following DNA replication until its cleavage during mitosis thereby enabling faithful segregation of sister chromatids into two daughter cells. Recent cancer genomics analyses have discovered a high frequency of somatic mutations in the genes encoding the core cohesin subunits as well as cohesin regulatory factors (e.g. NIPBL, PDS5B, ESPL1) in a select subset of human tumors including glioblastoma, Ewing sarcoma, urothelial carcinoma, acute myeloid leukemia, and acute megakaryoblastic leukemia. Herein we review these studies including discussion of the functional significance of cohesin inactivation in tumorigenesis and potential therapeutic mechanisms to selectively target cancers harboring cohesin mutations. [BMB Reports 2014; 47(6): 299-310] PMID:24856830

Solomon, David A.; Kim, Jung-Sik; Waldman, Todd

2014-01-01

130

BCS1L gene mutation causing GRACILE syndrome: case report.  

PubMed

GRACILE syndrome is a rare autosomal recessive disease characterized by fetal growth retardation, Fanconi type aminoaciduria, cholestasis, iron overload, profound lactic acidosis, and early death. It is caused by homozygosity for a missense mutation in the BCS1L gene. The BCS1L gene encodes a chaperone responsible for assembly of respiratory chain complex III. Here we report that a homozygous mutation c.296C > T (p.P99L), in the first exon of BCS1L gene found in an affected 2-month-old boy of asymptomatic consanguineous parents results in GRACILE syndrome. This genotype is associated with a severe clinical presentation. So far no available treatments have changed the fatal course of the disease, and the metabolic disturbance responsible is still not clearly identified. Therefore, providing prenatal diagnosis in families with previous affected infants is of major importance. Mitochondrial disorders are an extremely heterogeneous group of diseases sharing, in common, the fact that they all ultimately impair the function of the mitochondrial respiratory chain. A clinical picture with fetal growth restriction, postnatal lactacidosis, aminoaciduria, hypoglycemia, coagulopathy, elevated liver enzymes, and cholestasis should direct investigations on mitochondrial disorder. PMID:24655110

Kasapkara, Çi?dem Seher; Tümer, Leyla; Ezgü, Fatih Suheyl; Küçükçongar, Aynur; Hasano?lu, Alev

2014-07-01

131

Mutations in ?- and ?-tubulin encoding genes: implications in brain malformations.  

PubMed

The tubulin gene family is mainly expressed in post-mitotic neurons during cortical development with a specific spatial and temporal expression pattern. Members of this family encode dimeric proteins consisting of two closely related subunits (? and ?), representing the major constituents of microtubules. Tubulin genes play a crucial role in the mechanisms of the Central Nervous System development such as neuronal migration and axonal guidance (axon outgrowth and maintenance). Different mutations in ?/?-tubulin genes (TUBA1A, TUBA8, TUBB2A, TUBB4A, TUBB2B, TUBB3, and TUBB) might alter the dynamic properties and functions of microtubules in several ways, effecting a reduction in the number of functional tubulin heterodimers and causing alterations in GTP binding and disruptions of the binding of other proteins to microtubules (motor proteins and other microtubule interacting proteins). In recent years an increasing number of brain malformations has been associated with mutations in tubulin genes: malformations of cortical development such as lissencephaly and various grades of gyral disorganization, focal or diffuse polymicrogyria and open or closed-lips schizencephaly as likely consequences of an altered neuronal migration process; abnormalities or agenesis of the midline commissural structures (anterior commissure, corpus callosum and fornix), hypoplasia of the oculomotor and optic nerves, dysmorphisms of the hind-brain as expression of axon guidance disorders. Dysmorphisms of the basal ganglia (fusion between the caudate nucleus and putamen with absence of the anterior limb of the internal capsule) and hippocampi were also observed. A rare form of leukoencephalopathy characterized by hypomyelination with atrophy of the basal ganglia an cerebellum (H-ABC) was also recently described. The present review, describing the structural and functional features of tubulin genes, aims to revise the main cerebral associated malformations and related clinical aspects, suggesting a genotype-phenotype correlation. PMID:25008804

Romaniello, Romina; Arrigoni, Filippo; Bassi, Maria Teresa; Borgatti, Renato

2015-03-01

132

Identifying photoreceptors in blind eyes caused by RPE65 mutations: Prerequisite for human gene therapy success  

Microsoft Academic Search

Mutations in RPE65, a gene essential to normal operation of the visual (retinoid) cycle, cause the childhood blindness known as Leber congenital amaurosis (LCA). Retinal gene therapy restores vision to blind canine and murine models of LCA. Gene therapy in blind humans with LCA from RPE65 mutations may also have potential for success but only if the retinal photoreceptor layer

Samuel G. Jacobson; Tomas S. Aleman; Artur V. Cideciyan; Alexander Sumaroka; Sharon B. Schwartz; Elizabeth A. M. Windsor; Elias I. Traboulsi; Elise Heon; Steven J. Pittler; Ann H. Milam; Albert M. Maguire; Krzysztof Palczewski; Edwin M. Stone; Jean Bennett

2005-01-01

133

[Rapid screening of katG gene mutation in isoniazid-resistant Mycobacterium tuberculosis  

PubMed

OBJECTIVE: To evaluate the relationship between katG gene mutation and isoniazid (INH) resistance and to develop a rapid screening method of point mutation in the katG gene associated with MTB resistance. METHODS: Twenty-four clinical isolates of MTB with 8 INH resigtance isolates and 16 INH-sensitive isolates were analyzed by PCR-RFLP, with the H(37)Rv reference strain as the control. RESULTS: G-->C point mutations were detected in 7 of 8 isoniazid-resistant strains and no gene mutation was shown in 16 isoniazid-sensitive isolates. The sensitivity and specificity were 87.5 % and 100 % respectively. No katG gene sequence deletion was observed in any specimen. CONCLUSION: Our results suggest katG gene mutation is one of the most important mechanisms of INH-resistant TB. PCR-RFLP may be useful in detection of katG gene mutation. PMID:12596308

Huo, Ya-Nan; Ge, Chao-Rong

2002-06-01

134

A mutation in the thyroid hormone receptor alpha gene.  

PubMed

Thyroid hormones exert their effects through alpha (TR?1) and beta (TR?1 and TR?2) receptors. Here we describe a child with classic features of hypothyroidism (growth retardation, developmental retardation, skeletal dysplasia, and severe constipation) but only borderline-abnormal thyroid hormone levels. Using whole-exome sequencing, we identified a de novo heterozygous nonsense mutation in a gene encoding thyroid hormone receptor alpha (THRA) and generating a mutant protein that inhibits wild-type receptor action in a dominant negative manner. Our observations are consistent with defective human TR?-mediated thyroid hormone resistance and substantiate the concept of hormone action through distinct receptor subtypes in different target tissues. PMID:22168587

Bochukova, Elena; Schoenmakers, Nadia; Agostini, Maura; Schoenmakers, Erik; Rajanayagam, Odelia; Keogh, Julia M; Henning, Elana; Reinemund, Jana; Gevers, Evelien; Sarri, Margarita; Downes, Kate; Offiah, Amaka; Albanese, Assunta; Halsall, David; Schwabe, John W R; Bain, Murray; Lindley, Keith; Muntoni, Francesco; Vargha-Khadem, Faraneh; Khadem, Faraneh Vargha; Dattani, Mehul; Farooqi, I Sadaf; Gurnell, Mark; Chatterjee, Krishna

2012-01-19

135

Mutations of the cystic fibrosis gene in patients with chronic pancreatitis  

Microsoft Academic Search

OBJECTIVE:Several studies have reported an increased frequency of cystic fibrosis gene mutations in idiopathic but not in alcoholic chronic pancreatitis. The impact of cystic fibrosis gene mutations on the long-term course of chronic pancreatitis has not been analyzed. The aim of our study was to determine the frequency of cystic fibrosis gene mutations in patients with chronic pancreatitis with long-term

Kaspar Truninger; Naseem Malik; Rudolf W. Ammann; Beat Muellhaupt; Burkardt Seifert; Hans-Jakob Müller; Hubert E. Blum

2001-01-01

136

Genetic syndromes caused by mutations in epigenetic genes.  

PubMed

The orchestrated organization of epigenetic factors that control chromatin dynamism, including DNA methylation, histone marks, non-coding RNAs (ncRNAs) and chromatin-remodeling proteins, is essential for the proper function of tissue homeostasis, cell identity and development. Indeed, deregulation of epigenetic profiles has been described in several human pathologies, including complex diseases (such as cancer, cardiovascular and neurological diseases), metabolic pathologies (type 2 diabetes and obesity) and imprinting disorders. Over the last decade it has become increasingly clear that mutations of genes involved in epigenetic mechanism, such as DNA methyltransferases, methyl-binding domain proteins, histone deacetylases, histone methylases and members of the SWI/SNF family of chromatin remodelers are linked to human disorders, including Immunodeficiency Centromeric instability Facial syndrome 1, Rett syndrome, Rubinstein-Taybi syndrome, Sotos syndrome or alpha-thalassemia/mental retardation X-linked syndrome, among others. As new members of the epigenetic machinery are described, the number of human syndromes associated with epigenetic alterations increases. As recent examples, mutations of histone demethylases and members of the non-coding RNA machinery have recently been associated with Kabuki syndrome, Claes-Jensen X-linked mental retardation syndrome and Goiter syndrome. In this review, we describe the variety of germline mutations of epigenetic modifiers that are known to be associated with human disorders, and discuss the therapeutic potential of epigenetic drugs as palliative care strategies in the treatment of such disorders. PMID:23370504

Berdasco, María; Esteller, Manel

2013-04-01

137

The landscape of cancer genes and mutational processes in breast cancer  

PubMed Central

All cancers carry somatic mutations in their genomes. A subset, known as driver mutations, confer clonal selective advantage on cancer cells and are causally implicated in oncogenesis1, and the remainder are passenger mutations. The driver mutations and mutational processes operative in breast cancer have not yet been comprehensively explored. Here we examine the genomes of 100 tumours for somatic copy number changes and mutations in the coding exons of protein-coding genes. The number of somatic mutations varied markedly between individual tumours. We found strong correlations between mutation number, age at which cancer was diagnosed and cancer histological grade, and observed multiple mutational signatures, including one present in about ten per cent of tumours characterized by numerous mutations of cytosine at TpC dinucleotides. Driver mutations were identified in several new cancer genes including AKT2, ARID1B, CASP8, CDKN1B, MAP3K1, MAP3K13, NCOR1, SMARCD1 and TBX3. Among the 100 tumours, we found driver mutations in at least 40 cancer genes and 73 different combinations of mutated cancer genes. The results highlight the substantial genetic diversity underlying this common disease. PMID:22722201

Stephens, Philip J.; Tarpey, Patrick S.; Davies, Helen; Loo, Peter Van; Greenman, Chris; Wedge, David C.; Nik-Zainal, Serena; Martin, Sancha; Varela, Ignacio; Bignell, Graham R.; Yates, Lucy R.; Papaemmanuil, Elli; Beare, David; Butler, Adam; Cheverton, Angela; Gamble, John; Hinton, Jonathan; Jia, Mingming; Jayakumar, Alagu; Jones, David; Latimer, Calli; Lau, King Wai; McLaren, Stuart; McBride, David J.; Menzies, Andrew; Mudie, Laura; Raine, Keiran; Rad, Roland; Chapman, Michael Spencer; Teague, Jon; Easton, Douglas; Langerřd, Anita; OSBREAC; Lee, Ming Ta Michael; Shen, Chen-Yang; Tee, Benita Tan Kiat; Huimin, Bernice Wong; Broeks, Annegien; Vargas, Ana Cristina; Turashvili, Gulisa; Martens, John; Fatima, Aquila; Miron, Penelope; Chin, Suet-Feung; Thomas, Gilles; Boyault, Sandrine; Mariani, Odette; Lakhani, Sunil R.; van de Vijver, Marc; van ’t Veer, Laura; Foekens, John; Desmedt, Christine; Sotiriou, Christos; Tutt, Andrew; Caldas, Carlos; Reis-Filho, Jorge S.; Aparicio, Samuel A. J. R.; Salomon, Anne Vincent; Břrresen-Dale, Anne-Lise; Richardson, Andrea L.; Campbell, Peter J.; Futreal, P. Andrew; Stratton, Michael R.

2012-01-01

138

Mutation analysis of the Fanconi Anemia Gene FACC  

SciTech Connect

Fanconi anemia (FA) is a genetically heterogeneous autosomal recessive disorder characterized by a unique hypersensitivity of cells to DNA cross-linking agents; a gene for complementation group C (FACC) has recently been cloned. The authors have amplified FACC exons with their flanking intron sequences from genomic DNA from 174 racially and ethnically diverse families in the International Fanconi Anemia Registry and have screened for mutations by using SSCP analysis. They have identified eight different variants in 32 families; three were detected in exon 1, one in exon 4, one in intron 4, two in exon 6, and one in exon 14. Two of the eight variants, in seven families, did not segregate with the disease allele in multiplex families, suggesting that these variants represented benign polymorphisms. Disease-associated mutations in FACC were detected in a total of 25 (14.4%) of 174 families screened. The most frequent mutations were IVS4 + 4 A [yields] T (intron 4; 12 families) and 322delG (exon 1; 9 families). Other, less common mutations include Q13X in exon 1, R185X and D195V in exon 6, and L554P in exon 14. The polymorphisms were S26F in exon 1 and G139E in exon 4. All patients in the study with 322delG, Q13X, R185X, and D195V are of northern or eastern European or southern Italian ancestry, and 18 of 19 have a mild form of the disease, while the 2 patients with L554P, both from the same family, have a severe phenotype. All 19 patients with IVS4 + 4 A [yields] T have Jewish ancestry and have a severe phenotype. 19 refs., 1 fig., 3 tabs.

Verlander, P.C.; Lin, J.D.; Udono, M.U.; Zhang, Q.; Auerbach, A.D. (Rockefeller Univ., New York, NY (United States)); Gibson, R.A.; Mathew, C.G. (Guy's Hospital, London (United Kingdom))

1994-04-01

139

Neuropathy Target Esterase Gene Mutations Cause Motor Neuron Disease  

PubMed Central

The possibility that organophosphorus (OP) compounds contribute to motor neuron disease (MND) is supported by association of paraoxonase 1 polymorphisms with amyotrophic lateral sclerosis (ALS) and the occurrence of MND in OP compound-induced delayed neuropathy (OPIDN), in which neuropathy target esterase (NTE) is inhibited by organophosphorylation. We evaluated a consanguineous kindred and a genetically unrelated nonconsanguineous kindred in which affected subjects exhibited progressive spastic paraplegia and distal muscle wasting. Affected subjects resembled those with OPIDN and those with Troyer Syndrome due to SPG20/spartin gene mutation (excluded by genetic linkage and SPG20/spartin sequence analysis). Genome-wide analysis suggested linkage to a 22 cM homozygous locus (D19S565 to D19S884, maximum multipoint LOD score 3.28) on chromosome 19p13 to which NTE had been mapped (GenBank AJ004832). NTE was a candidate because of its role in OPIDN and the similarity of our patients to those with OPIDN. Affected subjects in the consanguineous kindred were homozygous for disease-specific NTE mutation c.3034A?G that disrupted an interspecies conserved residue (M1012V) in NTE's catalytic domain. Affected subjects in the nonconsanguineous family were compound heterozygotes: one allele had c.2669G?A mutation, which disrupts an interspecies conserved residue in NTE's catalytic domain (R890H), and the other allele had an insertion (c.2946_2947insCAGC) causing frameshift and protein truncation (p.S982fs1019). Disease-specific, nonconserved NTE mutations in unrelated MND patients indicates NTE's importance in maintaining axonal integrity, raises the possibility that NTE pathway disturbances contribute to other MNDs including ALS, and supports the role of NTE abnormalities in axonopathy produced by neuropathic OP compounds. PMID:18313024

Rainier, Shirley; Bui, Melanie; Mark, Erin; Thomas, Donald; Tokarz, Debra; Ming, Lei; Delaney, Colin; Richardson, Rudy J.; Albers, James W.; Matsunami, Nori; Stevens, Jeff; Coon, Hilary; Leppert, Mark; Fink, John K.

2008-01-01

140

Three new mutations in the uroporphyrinogen decarboxylase gene in familial porphyria cutanea tarda. Mutation in brief no. 237. Online.  

PubMed

We have characterised three new mutations in the uroporphyrinogen decarboxylase gene in familial porphyria cutanea tarda. The first of these was a G to A substitution in the 5' splice junction of exon 4 which generated an mRNA that lacked exon 4. The second was a nonsense mutation in exon 5 which changed the arginine residue at position 142 to a stop codon, and the third mutation, also in exon 5, was a triple base substitution from nucleotide position 417 to 419. This mutation encompassed two codons but only changed the amino acid predicted from the second codon, resulting in the replacement of valine with glutamine at position 134. This missense mutation has been described previously by Meguro et al. 1994, on one allele in a compound heterozygote with hepatoerythropoietic porphyria. This is the third case of an hepatoerythropoietic porphyria mutation in an individual diagnosed with familial porphyria cutanea tarda. PMID:10338097

McManus, J F; Begley, C G; Sassa, S; Ratnaike, S

1999-01-01

141

Genotype analysis of the NRF2 gene mutation in lung cancer.  

PubMed

Nuclear factor (erythroid derived 2)-like 2 (NRF2, gene name NFE2L2) gene mutations have been previously identified in lung cancers. The constitutive activation of NRF2 resulting from gene mutations has been correlated with the poor prognosis of patients with squamous cell lung cancer. However, DNA sequencing using PCR methods described to date is time-consuming and requires significant quantities of DNA. Thus, this existing approach is not suitable for a routine pre-therapeutic screening program. We genotyped the NRF2 gene mutation status in 262 surgically treated lung cancer cases using LightCycler analysis. The presence of the NRF2 gene mutation was confirmed by direct sequencing. We detected 6 cases (2.3%) with NRF2 gene mutations in our cohort, particularly smokers (P=0.04) with squamous histology (P=0.0001). NRF2 gene mutations were present in 10% (6/60) of the lung squamous cell carcinoma (SqCC) cases. The NRF2 gene mutation was exclusive of epidermal growth factor receptor mutations. The NRF2 gene mutation occurred with a tendency towards a higher frequency in male patients. Patients with the NRF2 gene mutation (n=22, 11 succumbed to disease) had a significantly worse prognosis when compared with the patients with the wild-type NRF2 gene (n=521, 98 succumbed to disease) from a larger cohort study (log-rank test, P<0.0001) even upon multivariate analysis. In our study, NRF2 gene mutations played a role in the prognosis of patients with SqCC of the lung. PMID:23545629

Sasaki, Hidefumi; Suzuki, Ayumi; Shitara, Masayuki; Hikosaka, Yu; Okuda, Katsuhiro; Moriyama, Satoru; Yano, Motoki; Fujii, Yoshitaka

2013-05-01

142

Mutations of the cystic fibrosis gene, but not cationic trypsinogen gene, are associated with recurrent or chronic idiopathic pancreatitis  

Microsoft Academic Search

OBJECTIVE:We investigated whether mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene and cationic trypsinogen gene are associated with recurrent acute, or chronic idiopathic pancreatitis.METHODS:Twenty patients with idiopathic pancreatitis (11 women, nine men; mean age, 30 yr) were studied for the presence of a CFTR mutation by screening the genomic DNA for more than 30 mutations and variants in

J Ockenga; M Stuhrmann; M Ballmann; N Teich; V Keim; T Dörk; M. P Manns

2000-01-01

143

Mutagenesis in cloned yeast genes. Mutation frequencies in a yeast gene in plasmid and chromosome  

SciTech Connect

Yeast cells were transformed with o-methyl-hydroxylamine-treated plasmid DNA. A collection of mutants possessing a mutated allele of the ADE2 gene in the plasmid was selected. The mutations were subjected to interallelic complementation and suppression-induced interallelic complementation tests. Some of the mutations were imparted to the chromosome via the conversion mechanism. Three pairs of strains, each of which carried an identical mutant allele in the plasmid and chromosome, were picked up. These alleles in the plasmid and chromosome were back-mutated by UV light and hydroxylaminopurine (HAP) and the results were compared. The plasmid alleles were shown to mutate less efficiently on exposure to UV light than to HAP. The HAP-induced mutation rate was 8-10 times higher in the plasmid than in the chromosome, which apparently reflected the plurality of plasmid copies in the cell. After UV irradiation the difference was only two- or threefold; the reason for this difference might be a different repair efficiency in chromosome and plasmid.

Gracheva, L.M.; Kasinova, G.V.; Korolev, V.G.; Fedorova, I.V.

1989-01-01

144

Linkage and mutational analysis of familial Alzheimer disease kindreds for the APP gene region  

Microsoft Academic Search

A large number of familial Alzheimer disease (FAD) kindreds were examined to determine whether mutations in the amyloid precursor protein (APP) gene could be responsible for the disease. Previous studies have identified three mutations at APP codon 717 which are pathogenic for Alzheimer disease (AD). Samples from affected subjects were examined for mutations in exons 16 and 17 of the

K. Kamino; L. Anderson; S. Odahl; E. Nemens; T. D. Bird; G. D. Schellenberg; E. M. Wijsman; W. Kukall; E. Larson; L. L. Heston

1992-01-01

145

Mutation Hotspots Due to Sunlight in the p53 Gene of Nonmelanoma Skin Cancers  

Microsoft Academic Search

To identify the sites in the p53 tumor suppressor gene most susceptible to carcinogenic mutation by sunlight, the entire coding region of 27 basal cell carcinomas (BCCs) of the skin was sequenced. Fifty-six percent of tumors contained mutations, and these were UV-like: primarily CC --> TT or C --> T changes at dipyrimidine sites. Such mutations can alter more than

Annemarie Ziegler; David J. Leffell; Subrahmanyam Kunala; Harsh W. Sharma; Mae Gailani; Jeffrey A. Simon; Alan J. Halperin; Howard P. Baden; Philip E. Shapiro; Allen E. Bale; Douglas E. Brash

1993-01-01

146

Analysis of RAS Gene Mutations in Acute Myeloid Leukemia by Polymerase Chain Reaction and Oligonucleotide Probes  

Microsoft Academic Search

In vitro DNA amplification followed by oligonucleotide dot blot analysis were used to study RAS gene mutations in acute myeloid leukemia (AML). Fifty-two presentation AML DNAs were screened for mutations in codons 12, 13, and 61 of NRAS and in codons 12 and 61 of KRAS and HRAS. Fourteen (27%) contained mutations--all in NRAS and predominantly in codon 12. The

Christine J. Farr; Randall K. Saiki; Henry A. Erlich; Frank McCormick; Christopher J. Marshall

1988-01-01

147

Sodium channel gene family: epilepsy mutations, gene interactions and modifier effects  

PubMed Central

The human sodium channel family includes seven neuronal channels that are essential for the initiation and propagation of action potentials in the CNS and PNS. In view of their critical role in neuronal firing and their strong sequence conservation during evolution, it is not surprising that mutations in the sodium channel genes are responsible for a growing spectrum of channelopathies. Nearly 700 mutations of the SCN1A gene have been identified in patients with Dravet's syndrome (severe myoclonic epilepsy of infancy), making this the most commonly mutated gene in human epilepsy. A small number of mutations have been found in SCN2A, SCN3A and SCN9A, and studies in the mouse suggest that SCN8A may also contribute to seizure disorders. Interactions between genetic variants of SCN2A and KCNQ2 in the mouse and variants of SCN1A and SCN9A in patients provide models of potential genetic modifier effects in the more common human polygenic epilepsies. New methods for generating induced pluripotent stem cells and neurons from patients will facilitate functional analysis of amino acid substitutions in channel proteins. Whole genome sequencing and exome sequencing in patients with epilepsy will soon make it possible to detect multiple variants and their interactions in the genomes of patients with seizure disorders. PMID:20351042

Meisler, Miriam H; O’Brien, Janelle E; Sharkey, Lisa M

2010-01-01

148

A novel alpha-thalassemia nonsense mutation in HBA2: C.382 A > T globin gene.  

PubMed

In this study, a new alpha globin gene mutation on the ?2-globin gene is reported. This mutation resulted in a Lys > stop codon substitution at position 127 which was detected in four individuals (three males and one female). DNA sequencing revealed this mutation in unrelated persons in Khuzestan province, Southwestern Iran of Lor ethnicity. This mutation caused no severe hematological abnormalities in the carriers. From the nature of substituted residues in ?2-globin, it is widely expected that this mutation leads to unstable and truncated protein and should be detected in couples at risk for ?-thalassemia. PMID:24979558

Hamid, Mohammad; Bokharaei Merci, Hanieh; Galehdari, Hamid; Saberi, Ali Hossein; Kaikhaei, Bijan; Mohammadi-Anaei, Marziye; Ahmadzadeh, Ahmad; Shariati, Gholamreza

2014-07-01

149

Chronic inflammatory state in sickle cell anemia patients is associated with HBB(*)S haplotype.  

PubMed

The chronic inflammatory state in sickle cell anemia (SCA) is associated with several factors such as the following: endothelial damage; increased production of reactive oxygen species; hemolysis; increased expression of adhesion molecules by leukocytes, erythrocytes, and platelets; and increased production of proinflammatory cytokines. Genetic characteristics affecting the clinical severity of SCA include variations in the hemoglobin F (HbF) level, coexistence of alpha-thalassemia, and the haplotype associated with the HbS gene. The different haplotypes of SCA are Bantu, Benin, Senegal, Cameroon, and Arab-Indian. These haplotypes are associated with ethnic groups and also based on the geographical origin. Studies have shown that the Bantu haplotype is associated with higher incidence of clinical complications than the other haplotypes and is therefore considered to have the worst prognosis. This study aimed to evaluate the profile of the proinflammatory cytokines interleukin-6, tumor necrosis factor-?, and interleukin-17 in patients with SCA and also to assess the haplotypes associated with beta globin cluster S (HBB(*)S). We analyzed a total of 62 patients who had SCA and had been treated with hydroxyurea; they had received a dose ranging between 15 and 25 (20.0±0.6)mg/kg/day for 6-60 (18±3.4)months; their data were compared with those for 30 normal individuals. The presence of HbS was detected and the haplotypes of the beta S gene cluster were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Our study demonstrated that SCA patients have increased inflammatory profile when compared to the healthy individuals. Further, analysis of the association between the haplotypes and inflammatory profile showed that the levels of IL-6 and TNF-? were greater in subjects with the Bantu/Bantu haplotype than in subjects with the Benin/Benin haplotype. The Bantu/Benin haplotype individuals had lower levels of cytokines than those with the Bantu/Bantu haplotype and greater levels than those of subjects with the Benin/Benin haplotype. For IL-17, a slight trend toward decreased levels was observed in the subjects with the Benin/Benin haplotype, when compared to those with the Bantu/Bantu and Bantu/Benin haplotypes; however, this difference was not statistically significant. Our results show that genetic polymorphisms in sickle cell anemia are associated with the inflammatory profile. PMID:24290434

Bandeira, Izabel C J; Rocha, Lillianne B S; Barbosa, Maritza C; Elias, Darcielle B D; Querioz, José A N; Freitas, Max Vitor Carioca; Gonçalves, Romélia P

2014-02-01

150

C-kit and PDGFRA gene mutations in triple negative breast cancer  

PubMed Central

In this study, we evaluated C-kit immunohistochemical expression and C-kit and platelet derived growth factor receptor A (PDGFRA) gene mutations in triple negative breast cancer. 171 cases were analyzed by immunohistochemical staining for the expression of C-kit and 45 cases, including 10 C-kit negative cases and 35 C-kit positive cases, were performed for C-kit gene mutations in exons 9, 11, 13 and 17 and PDGFRA gene mutations in exons 12 and 18. C-kit expression was detected in 42.1% of triple negative breast cancers. Only 1 activating mutation was detected in exon 11 of C-kit gene in 1 case. No activating mutations were found in the other 44 cases. C-kit expression is a frequent finding in triple negative breast cancers; 1 activating mutation which was also found in gastrointestinal stromal tumors was detected; a few cases might benefit from imatinib. PMID:25120810

Zhu, Yun; Wang, Yan; Guan, Bing; Rao, Qiu; Wang, Jiandong; Ma, Henghui; Zhang, Zhihong; Zhou, Xiaojun

2014-01-01

151

Mutation screening of the RYR1 gene in malignant hyperthermia: Detection of a novel Tyr to ser mutation in a pedigree with associated centrl cores  

Microsoft Academic Search

The ryanodine receptor gene (RYR1) has been shown to be mutated in a small number of malignant hyperthermia (MH) predigrees. Missense mutations in this gene have also been identified in two families with central core disease (CCD), a rare myopathy closely associated with MH. In an effort to identify other RYR1 mutations responsible for MH and CCD, we used a

K. A. Quane; K. E. Keating; J. M. S. Healy

1994-01-01

152

MECP2 and CDKL5 gene mutation analysis in Chinese patients with Rett syndrome  

Microsoft Academic Search

Rett syndrome (RTT) is a progressive neurodevelopmental disorder that is caused by mutations in the X-linked methyl-CpG-binding\\u000a protein2 (MECP2) gene. In this study, the MECP2 sequences in 121 unrelated Chinese patients with classical or atypical RTT were screened for deletions and mutations. In\\u000a all, we identified 45 different MECP2 mutations in 102 of these RTT patients. The p. T158M mutation

Mei-rong Li; Hong Pan; Xin-Hua Bao; Yu-Zhi Zhang; Xi-Ru Wu

2007-01-01

153

Muscle disease caused by mutations in the skeletal muscle alpha-actin gene (ACTA1)  

Microsoft Academic Search

Mutations in the skeletal muscle alpha-actin gene (ACTA1) associated with congenital myopathy with excess of thin myofilaments, nemaline myopathy and intranuclear rod myopathy were first described in 1999. At that time, only 15 different missense mutations were known in ACTA1. More than 60 mutations have now been identified. This review analyses this larger spectrum of mutations in ACTA1. It investigates

John C. Sparrowa; Kristen J. Nowakb; Hayley J. Durlingb; Alan H. Beggse; Carina Wallgren-Petterssonf; Norma Romerog; Ikuya Nonakah; Nigel G. Laingb

154

Muscle disease caused by mutations in the skeletal muscle alpha-actin gene ( ACTA1)  

Microsoft Academic Search

Mutations in the skeletal muscle alpha-actin gene (ACTA1) associated with congenital myopathy with excess of thin myofilaments, nemaline myopathy and intranuclear rod myopathy were first described in 1999. At that time, only 15 different missense mutations were known in ACTA1. More than 60 mutations have now been identified. This review analyses this larger spectrum of mutations in ACTA1. It investigates

John C. Sparrow; Kristen J. Nowak; Hayley J. Durling; Alan H. Beggs; Carina Wallgren-Pettersson; Norma Romero; Ikuya Nonaka; Nigel G. Laing

2003-01-01

155

Identification of p53 Gene Mutations in Bladder Cancers and Urine Samples  

Microsoft Academic Search

Although bladder cancers are very common, little is known about their molecular pathogenesis. In this study, invasive bladder cancers were evaluated for the presence of gene mutations in the p53 suppressor gene. Of 18 tumors evaluated, 11 (61 percent) were found to have genetic alterations of p53. The alterations included ten point mutations resulting in single amino acid substitutions, and

David Sidransky; Andrew von Eschenbach; Yvonne C. Tsai; Peter Jones; Ian Summerhayes; Fray Marshall; Meera Paul; Pearl Green; Philip Frost; Bert Vogelstein

1991-01-01

156

Three Classes of Genes Mutated In Colorectal Cancers with Chromosomal Instability  

Microsoft Academic Search

Although most colorectal cancers are chromosomally unstable, the basis for this instability has not been defined. To determine whether genes shown to cause chromosomal instability in model systems were mutated in colorectal cancers, we identified their human homologues and determined their sequence in a panel of colorectal cancers. We found 19 somatic mutations in five genes representing three distinct instability

Zhenghe Wang; Jordan M. Cummins; Dong Shen; Daniel P. Cahill; Prasad V. Jallepalli; Tian-Li Wang; D. Williams Parsons; Giovanni Traverso; Mark Awad; Natalie Silliman; Janine Ptak; Steve Szabo; James K. V. Willson; Sanford D. Markowitz; Michael L. Goldberg; Roger Karess; Kenneth W. Kinzler; Bert Vogelstein; Victor E. Velculescu; Christoph Lengauer

2004-01-01

157

Mutations in the gene encoding gap junction protein ?–3 associated with autosomal dominant hearing impairment  

Microsoft Academic Search

Hearing impairment is the most commonly occurring condition that affects the ability of humans to communicate. More than 50% of the cases of profound early-onset deafness are caused by genetic factors. Over 40 loci for non-syndromic deafness have been genetically mapped, and mutations in several genes have been shown to cause hearing loss. Mutations in the gene encoding connexin 26

Chun-yu Liu; Bei-sha Tang; Qian Pan; Lei Huang; He-ping Dai; Bao-rong Zhang; Wei Xie; Dong-xu Hu; Duo Zheng; Xiao-liu Shi; De-an Wang; Kun Xia; Kuan-ping Yu; Xiao-dong Liao; Yong Feng; Yi-feng Yang; Jian-yun Xiao; Ding-hua Xie; Jian-zheng Huang

1999-01-01

158

Mutation of the PAX6 gene in patients with autosomal dominant keratitis  

Microsoft Academic Search

Autosomal dominant keratitis (ADK) is an eye disorder chiefly characterized by corneal opacification and vascularization and by foveal hypoplasia. Aniridia (shown recently to result from mutations in the PAX6 gene) has overlapping clinical findings and a similar pattern of inheritance with ADK. On the basis of these similarities, we used a candidate-gene approach to investigate whether mutations in the PAX6

F. Mirzayans; W. G. Pearce; I. M. MacDonald; M. A. Walter

1995-01-01

159

Leber congenital amaurosis due to RPE65 mutations and its treatment with gene therapy  

Microsoft Academic Search

Leber congenital amaurosis (LCA) is a rare hereditary retinal degeneration caused by mutations in more than a dozen genes. RPE65, one of these mutated genes, is highly expressed in the retinal pigment epithelium where it encodes the retinoid isomerase enzyme essential for the production of chromophore which forms the visual pigment in rod and cone photoreceptors of the retina. Congenital

Artur V. Cideciyan

2010-01-01

160

The role of hemochromatosis susceptibility gene mutations in protecting against iron deficiency in celiac disease  

Microsoft Academic Search

Background & Aims: Celiac disease and hereditary hemochromatosis are common HLA-defined conditions in northwestern Europe. We sought to determine whether there is a genetic relationship between the 2 diseases and if hemochromatosis susceptibility gene (HFE) mutations are protective against iron deficiency in celiac disease. Methods: Polymerase chain reaction amplification using sequence-specific primers capable of identifying the 2 HFE gene mutations

Jeffrey R. Butterworth; Brian T. Cooper; William M. C. Rosenberg; Michael Purkiss; Shirley Jobson; Mark Hathaway; David Briggs; W. Martin Howell; Gordon M. Wood; David H. Adams; Tariq H. Iqbal

2002-01-01

161

Proteolipid Protein Gene Mutation Induces Altered Ventilatory Response to Hypoxia in the Myelin-Deficient Rat  

Microsoft Academic Search

Pelizaeus Merzbacher disease is an X-linked dysmyelinating disorder of the CNS, resulting from mutations in the proteolipid protein (PLP) gene. An animal model for this disorder, the myelin-deficient (MD) rat, carries a point mutation in the PLP gene and exhibits a phenotype similar to the fatal, connatal disease, including extensive dysmyelination, tremors, ataxia, and death at approximately post- natal day

Martha J. Miller; Musa A. Haxhiu; Paraskevi Georgiadis; Tatyana I. Gudz; Cindy D. Kangas; Wendy B. Macklin

2003-01-01

162

High Frequency of Coexistent Mutations of PIK3CA and PTEN Genes in Endometrial Carcinoma  

Microsoft Academic Search

The phosphatidylinositol 3V-kinase (PI3K) pathway is activated in many human cancers. In addition to inactivation of the PTEN tumor suppressor gene, mutations or amplifications of the catalytic subunit A of PI3K (PIK3CA) have been reported. However, the coexistence of mutations in these two genes seems exceedingly rare. As PTEN mutations occur at high frequency in endometrial carcinoma, we screened 66

Katsutoshi Oda; David Stokoe; Yuji Taketani; Frank McCormick

2005-01-01

163

K- ras gene mutations: an unfavorable prognostic marker in stage I lung adenocarcinoma  

Microsoft Academic Search

Activation of K-ras gene by point mutations, a common finding in lung adenocarcinomas, has been suggested to decrease patient survival. We investigated 109 lung adenocarcinomas, mostly small, peripheral, stage I tumours (81\\/109) for presence of K-ras gene mutations at codons 12 and 13. Mutations were detected by denaturing gradient gel electrophoresis analysis of specific sequences amplified by polymerase chain reaction

E. M. Silini; F. Bosi; E. Solcia; R. Fiocca; N. S. Pellegata; G. N. Ranzani; G. Volpato; A. Romano; S. Nazari; C. Tinelli

1994-01-01

164

Mutation update for GNE gene variants associated with GNE myopathy.  

PubMed

The GNE gene encodes the rate-limiting, bifunctional enzyme of sialic acid biosynthesis, uridine diphosphate-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE). Biallelic GNE mutations underlie GNE myopathy, an adult-onset progressive myopathy. GNE myopathy-associated GNE mutations are predominantly missense, resulting in reduced, but not absent, GNE enzyme activities. The exact pathomechanism of GNE myopathy remains unknown, but likely involves aberrant (muscle) sialylation. Here, we summarize 154 reported and novel GNE variants associated with GNE myopathy, including 122 missense, 11 nonsense, 14 insertion/deletions, and seven intronic variants. All variants were deposited in the online GNE variation database (http://www.dmd.nl/nmdb2/home.php?select_db=GNE). We report the predicted effects on protein function of all variants well as the predicted effects on epimerase and/or kinase enzymatic activities of selected variants. By analyzing exome sequence databases, we identified three frequently occurring, unreported GNE missense variants/polymorphisms, important for future sequence interpretations. Based on allele frequencies, we estimate the world-wide prevalence of GNE myopathy to be ?4-21/1,000,000. This previously unrecognized high prevalence confirms suspicions that many patients may escape diagnosis. Awareness among physicians for GNE myopathy is essential for the identification of new patients, which is required for better understanding of the disorder's pathomechanism and for the success of ongoing treatment trials. PMID:24796702

Celeste, Frank V; Vilboux, Thierry; Ciccone, Carla; de Dios, John Karl; Malicdan, May Christine V; Leoyklang, Petcharat; McKew, John C; Gahl, William A; Carrillo-Carrasco, Nuria; Huizing, Marjan

2014-08-01

165

Mutation analysis of the BRCA2 gene in breast\\/ovarian cancer Spanish families: identification of two new mutations  

Microsoft Academic Search

The recently isolated gene BRCA2 is responsible for about 45% of familial breast cancer and the majority of male breast cancer families. We have screened 12 high risk breast\\/ovarian Spanish families for mutations in BRCA2, using SSCP followed by direct sequencing. We have found mutations in four of our 12 families (33.3%), including two with male breast cancer. Three of

Ana Osorio; Mercedes Robledo; Jose Albertos; Jesús Andrade; Ana Barabash; Javier Ben??tez

1997-01-01

166

DPY19L2 gene mutations are a major cause of globozoospermia: identification of three novel point mutations.  

PubMed

Globozoospermia, characterized by round-headed spermatozoa without acrosomes, is a rare and severe teratozoospermia causing primary male infertility. Homozygous DPY19L2 deletions have been identified as the main cause of globozoospermia, blocking sperm head elongation and acrosome formation. Several previous studies showed a very different prevalence of DPY19L2 gene deletions among globozoospermic patients in cohorts with different sample sizes and in different ethnic background. And all the patients previously analyzed were mainly of European, North African and Middle Eastern origins. So far, only 11 different point mutations of the DPY19L2 gene have been reported. To investigate the prevalence of DPY19L2 gene mutations in Chinese patients with globozoospermia and whether we can identify new sequence variants in this study, we recruited a total of 16 globozoospermic patients. Excluding one of two brothers, molecular analysis for deletions and mutations in the DPY19L2 gene was performed on 15 genetically independent individuals. Four of the 15 genetically independent patients with globozoospermia were homozygous for the DPY19L2 deletion, 5 were homozygous for a point mutation including a nucleotide deletion c.1532delA (two patients), a multi-mutation consisting of a nucleotide deletion c.1679delT and a two-nucleotide deletion c.1681_1682delAC (c.[1679delT; 1681_1682delAC]) (one patient), a recurrent missense mutation R290H (one patient) and a missense mutation L330P (one patient). One additional patient had a heterozygous deletion in one allele but with no mutation identified in another allele. Overall, 60% of the patients (9/15) have a sequence variant of DPY19L2 in both alleles. This study confirms that the DPY19L2 mutations are the major cause of globozoospermia. Three novel point mutations and a recurrent missense mutation were found in this study, further broadening the spectrum of DPY19L2 mutations. PMID:23512994

Zhu, Fuxi; Gong, Fei; Lin, Ge; Lu, Guangxiu

2013-06-01

167

A missense mutation in the NF2 gene results in moderate and mild clinical phenotypes of neurofibromatosis type 2  

Microsoft Academic Search

Since the identification of the NF2 tumor suppressor gene in 1993, various mutations have been found in NF2-related tumors and in lymphocytes from NF2 patients. Most of the reported mutations result in truncated gene products. Missense mutations affecting the tumor suppressor are rare. These missense mutations would provide valuable information for the understanding of the function of the tumor suppressor,

Lan Kluwe; Victor-F. Mautner

1996-01-01

168

Recurrent and founder mutations in the PMS2 gene  

PubMed Central

Germline mutations in PMS2 are associated with Lynch syndrome (LS), the most common known cause of hereditary colorectal cancer. Mutation detection in PMS2 has been difficult due to the presence of several pseudogenes, but a custom-designed long-range PCR strategy now allows adequate mutation detection. Many mutations are unique. However some mutations are observed repeatedly, across individuals not known to be related, due to the mutation being either recurrent, arising multiple times de novo at hot spots for mutations, or of founder origin, having occurred once in an ancestor. Previously, we observed 36 distinct mutations in a sample of 61 independently ascertained Caucasian probands of mixed European background with PMS2 mutations. Eleven of these mutations were detected in more than one individual not known to be related and of these, six were detected more than twice. These six mutations accounted for 31 (51%) ostensibly unrelated probands. Here we performed genotyping and haplotype analysis in four mutations observed in multiple probands and found two (c.137G>T and exon 10 deletion) to be founder mutations, one (c.903G>T) a probable founder, and one (c.1A>G) where founder mutation status could not be evaluated. We discuss possible explanations for the frequent occurrence of founder mutations in PMS2. PMID:22577899

Tomsic, Jerneja; Senter, Leigha; Liyanarachchi, Sandya; Clendenning, Mark; Vaughn, Cecily P.; Jenkins, Mark A.; Hopper, John L.; Young, Joanne; Samowitz, Wade; de la Chapelle, Albert

2012-01-01

169

Reappraisal of the wrong-sign hbbŻ coupling and the study of h?Z?  

NASA Astrophysics Data System (ADS)

It has been pointed out recently that current experiments still allow for a two Higgs doublet model where the hbbŻ coupling (kDmb/v) is negative; a sign opposite to that of the Standard Model. Due to the importance of delayed decoupling in the hH+H- coupling, h??? improved measurements will have a strong impact on this issue. For the same reason, measurements or even bounds on h?Z? are potentially interesting. In this article, we revisit this problem, highlighting the crucial importance of h?VV, which can be understood with simple arguments. We show that the impacts on kD<0 models of both h?bbŻ and h??+?- are very sensitive to input values for the gluon fusion production mechanism; in contrast, h??? and h?Z? are not. We also inquire if the search for h?Z? and its interplay with h??? will impact the sign of the hbbŻ coupling. Finally, we study these issues in the context of the flipped two Higgs doublet model.

Fontes, Duarte; Romăo, J. C.; Silva, Joăo P.

2014-07-01

170

Mutation analysis of Leber congenital amaurosis?associated genes in patients with retinitis pigmentosa.  

PubMed

The genetic defects underlying approximately half of all retinitis pigmentosa (RP) cases are unknown. A number of genes responsible for Leber congenital amaurosis (LCA) may also cause RP when they are mutated. Our previous study revealed that variants in the most frequently mutated nine exons accounted for approximately half of the mutations detected in a cohort of patients with LCA. The aim of the present study was to detect mutations in LCA-associated genes in patients with RP using two different strategies. Sanger sequencing was used to screen mutations in the nine exons in 293 patients with RP and exome sequencing was used to detect variants in 12 LCA-associated genes in 157 of the 293 patients with RP and then to validate the variants by Sanger sequencing. Potential pathogenic mutations were identified in four patients with early onset RP, including homozygous CRB1 mutations in two patients, compound heterozygous CRB1 mutations in one patient and compound heterozygous CEP290 mutations in one patient. The present study indicated that mutations in CEP290 may also be associated with RP but not with LCA. With the exception of CEP290, the remaining 11 genes known to be associated with LCA but not with RP are unlikely to be a common cause of RP. PMID:25377065

Shen, Tao; Guan, Liping; Li, Shiqiang; Zhang, Jianguo; Xiao, Xueshan; Jiang, Hui; Yang, Jianhua; Guo, Xiangming; Wang, Jun; Zhang, Qingjiong

2015-03-01

171

Peptide nucleic acid probe detection of mutations in Mycobacterium tuberculosis genes associated with drug resistance.  

PubMed

The emergence of drug-resistant strains of Mycobacterium tuberculosis is a serious public health problem. Many of the specific gene mutations that cause drug resistance in M. tuberculosis are point mutations. We are developing a PCR-peptide nucleic acid (PNA)-based ELISA as a diagnostic method to recognize point mutations in genes associated with isoniazid and rifampin resistance in M. tuberculosis. Specific point mutation-containing sequences and wild-type sequences of cloned mycobacterial genes were PCR-amplified, denatured, and hybridized with PNA probes bound to microplate wells. Using 15-base PNA probes, we established the hybridization temperatures (50 degrees C-55 degrees C) and other experimental conditions suitable for detecting clinically relevant point mutations in the katG and rpoB genes. Hybridization of PCR-amplified sequences that contained these point mutations with complementary mutation-specific PNAs resulted in significant increases in ELISA response compared with hybridization using wild-type-specific PNAs. Conversely, PCR-amplified wild-type sequences hybridized much more efficiently with wild-type PNAs than with the mutation-specific PNAs. Using the M. tuberculosis cloned genes and PCR-PNA-ELISA format developed here, M. tuberculosis sequences containing point mutations associated with drug resistance can be identified in less than 24 h. PMID:11926172

Bockstahler, L E; Li, Z; Nguyen, N Y; Van Houten, K A; Brennan, M J; Langone, J J; Morris, S L

2002-03-01

172

Early onset of somatic mutation in immunoglobulin VH genes during the primary immune response  

PubMed Central

The dynamics of somatic mutation in Ig variable genes was investigated in order to define a population of B cells undergoing mutation. BALB/cJ mice were injected with PC-KLH, and splenic RNA was prepared 5, 7, and 13 d later. The mRNA was annealed to gamma constant region primers to make cDNA transcripts encoding VH genes. 103 cDNA clones corresponding to 18 different genes from the VH7183, VH3660, and VHS107 subfamilies were sequenced to identify mutation. VH genes had a low level of mutation on day 5 after immunization and accumulated more mutation by day 7 at a rate of 10(-3) mutations per nucleotide per generation. However, by day 13, the number of mutations per gene did not increase, and most of the substitutions encoded replacement amino acid changes that were clustered in the hypervariable regions, indicating that the mutational process was less active during the second week and that antigen selection had occurred. The data are consistent with a developmentally regulated mechanism in which mutation is activated during the first week of the primary immune response for a limited time period, after which selection acts to preserve the beneficial mutants. PMID:2499654

1989-01-01

173

Interaction between Mutations and Regulation of Gene Expression during Development of De Novo Antibiotic Resistance  

PubMed Central

Bacteria can become resistant not only by horizontal gene transfer or other forms of exchange of genetic information but also by de novo by adaptation at the gene expression level and through DNA mutations. The interrelationship between changes in gene expression and DNA mutations during acquisition of resistance is not well documented. In addition, it is not known whether the DNA mutations leading to resistance always occur in the same order and whether the final result is always identical. The expression of >4,000 genes in Escherichia coli was compared upon adaptation to amoxicillin, tetracycline, and enrofloxacin. During adaptation, known resistance genes were sequenced for mutations that cause resistance. The order of mutations varied within two sets of strains adapted in parallel to amoxicillin and enrofloxacin, respectively, whereas the buildup of resistance was very similar. No specific mutations were related to the rather modest increase in tetracycline resistance. Ribosome-sensed induction and efflux pump activation initially protected the cell through induction of expression and allowed it to survive low levels of antibiotics. Subsequently, mutations were promoted by the stress-induced SOS response that stimulated modulation of genetic instability, and these mutations resulted in resistance to even higher antibiotic concentrations. The initial adaptation at the expression level enabled a subsequent trial and error search for the optimal mutations. The quantitative adjustment of cellular processes at different levels accelerated the acquisition of antibiotic resistance. PMID:24841263

Händel, Nadine; Schuurmans, Jasper M.; Feng, Yanfang; Brul, Stanley

2014-01-01

174

Nuclear Gene-Induced Plastome Mutations in OENOTHERA HOOKERI. I. Genetic Analysis  

PubMed Central

A nuclear gene mutation in Oenothera hookeri increases the frequency of variegated sectors. The gene is recessive; the variegation is cytoplasmically transmitted. Once variegation is induced, the mutant gene is not required for its continued expression. The induced sectors may differ one from another. The gene expresses unique patterns of penetrance and of maternal effect. The genetic data implicate the chloroplasts as the site for the expression of variegation. The chloroplasts of O. parviflora are also subject to the action of the nuclear gene. Possible mechanisms by which a gene might cause chloroplasts to mutate are discussed. PMID:17248643

Epp, Melvin D.

1973-01-01

175

Atypical familial juvenile hyperuricemic nephropathy associated with a hepatocyte nuclear factor-1? gene mutation  

Microsoft Academic Search

Atypical familial juvenile hyperuricemic nephropathy associated with a hepatocyte nuclear factor-1? gene mutation.BackgroundFamilial juvenile hyperuricemic nephropathy (FJHN) is a dominantly inherited condition characterized by young-onset hyperuricemia, gout, and renal disease. The etiologic genes are unknown, although a locus on chromosome 16 has been identified in some kindreds. Mutations in the gene encoding hepatocyte nuclear factor (HNF)-1? have been associated with

Coralie Bingham; Sian Ellard; William G van't Hoff; H Anne Simmonds; Anthony M Marinaki; Michael K Badman; Peter H Winocour; Amanda Stride; Christopher R Lockwood; Anthony J Nicholls; Katharine R Owen; Ghislaine Spyer; Ewan R Pearson; Andrew T Hattersley

2003-01-01

176

Mutation Analysis of Autosomal Dominant Polycystic Kidney Disease Genes in Han Chinese  

Microsoft Academic Search

Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in two genes, PKD1 and PKD2. The complexity of these genes, particularly PKD1, has complicated genetic screening, though recent advances have provided new opportunities for amplifying these genes. In the Han Chinese population, no complete mutational analysis has previously been conducted across the entire span of PKD1 and PKD2. Here,

Shuzhong Zhang; Changlin Mei; Dianyong Zhang; Bing Dai; Bing Tang; Tianmei Sun; Haidan Zhao; Yukun Zhou; Lin Li; Yumei Wu; Wenjing Wang; Xuefei Shen; Ji Song

2005-01-01

177

K- ras gene point mutations in human endometrial carcinomas: correlation with clinicopathological features and patients' outcome  

Microsoft Academic Search

In order to evaluate the role of K-ras gene point mutations in the progression of endometrial carcinoma, we applied the polymerase chain reaction\\/restriction-fragment-length\\u000a polymorphism technique to 57 tumours surgically removed from women of Polish origin. We assessed the relationship between\\u000a K-ras gene activation and clinicopathological features as well as patients' outcome. Mutational activation in codon 12 of the K-ras gene

A. Semczuk; H. Berbe?; M. Kostuch; M. Cybulski; J. Wojcierowski; W. Baranowski

1998-01-01

178

A case of restless leg syndrome in a family with LRRK2 gene mutation.  

PubMed

LRRK2 gene mutations (PARK8) are a common cause of genetic Parkinson disease (PD). G2019S, the most frequent mutation, is responsible for both familial and sporadic cases of PD. The clinical picture is usually indistinguishable from that observed in idiopathic PD; however, a wide range of clinical presentations and pathological findings has been described. Restless leg syndrome (RLS) is a disabling sleep-related sensorimotor disorder whose pathogenesis is likely related to dopaminergic dysfunction. We report a 77-year-old woman with RLS and familial history of parkinsonism. The father, one sister, two cousins and one uncle were affected by PD. The proband and her sister were analyzed for mutations in LRRK2 gene and resulted to carry one heterozygous G2019S mutation in LRRK2 gene. The association between RLS and LRRK2 gene mutation may be casual, but it can hypothesized that RLS is a possible phenotypic presentation in PARK8. PMID:23227859

De Rosa, Anna; Guacci, Anna; Peluso, Silvio; Del Gaudio, Luigi; Massarelli, Marco; Barbato, Stefano; Criscuolo, Chiara; De Michele, Giuseppe

2013-04-01

179

Mutations in origin recognition complex gene ORC4 cause Meier-Gorlin syndrome.  

PubMed

Meier-Gorlin syndrome is a rare autosomal recessive genetic condition whose primary clinical hallmarks include small stature, small external ears and small or absent patellae. Using marker-assisted mapping in multiple families from a founder population and traditional coding exon sequencing of positional candidate genes, we identified three different mutations in the gene encoding ORC4, a component of the eukaryotic origin recognition complex, in five individuals with Meier-Gorlin syndrome. In two such individuals that were negative for mutations in ORC4, we found potential mutations in ORC1 and CDT1, two other genes involved in origin recognition. ORC4 is well conserved in eukaryotes, and the yeast equivalent of the human ORC4 missense mutation was shown to be pathogenic in functional assays of cell growth. This is the first report, to our knowledge, of a germline mutation in any gene of the origin recognition complex in a vertebrate organism. PMID:21358631

Guernsey, Duane L; Matsuoka, Makoto; Jiang, Haiyan; Evans, Susan; Macgillivray, Christine; Nightingale, Mathew; Perry, Scott; Ferguson, Meghan; LeBlanc, Marissa; Paquette, Jean; Patry, Lysanne; Rideout, Andrea L; Thomas, Aidan; Orr, Andrew; McMaster, Chris R; Michaud, Jacques L; Deal, Cheri; Langlois, Sylvie; Superneau, Duane W; Parkash, Sandhya; Ludman, Mark; Skidmore, David L; Samuels, Mark E

2011-04-01

180

p53 Gene Mutations Occur in Combination with 17p Allelic Deletions as Late Events in Colorectal Tumorigenesis1  

Microsoft Academic Search

Coordinate loss of one copy of the p53 gene and mutation of the remaining copy occur in colorectal carcinomas and in many other human malignancies. However, the prevalence of p53 gene mutations in carci nomas which maintain both parental copies of p53 has not previously been evaluated. Moreover, it is not known whether p53 gene mutations are limited to malignant

Suzanne J. Baker; Antonette C. Preisinger; J. Milburn Jessup; Christos Paraskeva; Sanford Markowitz; J. K. V. Willson; Bert Vogelstein

1990-01-01

181

KIT gene exon 11 mutations in canine malignant melanoma.  

PubMed

The proto-oncogene KIT encodes a receptor tyrosine kinase which has been shown to be upregulated in canine melanomas. KIT mutations lead to constitutive phosphorylation and activation of KIT in the absence of ligand binding. The presence of KIT mutations and KIT protein expression was examined in a cohort of 49 dogs with canine malignant melanoma. An exon 11 synonymous nucleotide 1743C?T mutation was identified in five cases in which one also harbored a L579P mutation. Tumors that harbored the KIT exon 11 mutation(s) correlated significantly with disease recurrence (P = 0.05). All 36 melanomas available for immunohistochemical analysis showed either weak (16 cases, 44.4%) or strong (20 cases, 55.6%) expression of the KIT protein. The five KIT mutation carriers were all strongly positive for KIT by immunohistochemical staining. These findings suggest that a subset of canine malignant melanomas harbors a KIT exon 11 mutation. PMID:23069279

Chu, Pei-Yi; Pan, Siou-Li; Liu, Chen-Hsuan; Lee, Jihjong; Yeh, Lih-Seng; Liao, Albert T

2013-05-01

182

Epidermal growth factor receptor in breast carcinoma: association between gene copy number and mutations  

PubMed Central

Background The epidermal growth factor receptor (EGFR) is an available target of effective anti-EGFR therapy for human breast cancer. The aim of this study was to assess the presence of EGFR gene amplification and mutations in breast cancer and to analyze the association between the statuses of these two gene alterations. Materials and methods EGFR gene amplification and mutations were investigated in formalin-fixed, paraffin-embedded tissues from 139 Chinese female patients with breast cancer by means of fluorescence in-situ hybridization (FISH) and fluorescently labeled real-time quantitative polymerase chain reaction (RT-PCR), respectively. Results EGFR gene amplification was observed in 46/139 (33.1%) of cases by FISH. Based on RT-PCR, 2/139 (1.4%) samples had EGFR gene mutations. Overall, only 1 (0.7%) of the cases was identified with both whole gene amplification and mutation, and 92 (66.2%) of cases were negative for both. High gene copy numbers of EGFR had significant correlation with the occurrence of EGFR protein expressions (P = 0.002). Conclusion In this study, EGFR mutations were presented in only two samples, indicating that EGFR mutations should not be employed in future trials with anti-EGFR therapies for breast cancer. However, EGFR whole gene amplification is frequently observed in patients with breast cancer. It will be of significant interest to investigate whether EGFR gene copy number is a suitable screening test for EGFR-targeted therapy for breast cancer. PMID:22132735

2011-01-01

183

Clinical, electrophysiological and genetic studies of two families with mutations in the GDAP1 gene.  

PubMed

Mutations in the gene for the ganglioside-induced-differentiation-associated-protein 1 on 8q21 were recently reported to cause autosomal recessive Charcot-Marie-Tooth sensorimotor neuropathy. We report a detailed clinical, electrophysiological and genetic study of two young patients harbouring missense GDAP1 mutations. The two patients presented severe neuropathy with an early onset. One of the mutations (Tyr279Cys) has never been hitherto reported. Electrophysiological investigations suggested a predominant axonal damage in both patients. Despite the similitude of the type of mutations and electromyographic features, the clinical course was different for the patients, highlighting the complexity of genotype/phenotype relationships among GDAP1 mutations. PMID:18991200

Rougeot, C; Chabrier, S; Camdessanche, J-P; Prieur, F; d'Anjou, M-C; Latour, P

2008-06-01

184

Whole Exome Sequencing Identifies Novel Recurrently Mutated Genes in Patients with Splenic Marginal Zone Lymphoma  

PubMed Central

The pathogenesis of splenic marginal zone lymphoma (SMZL) remains largely unknown. Recent high-throughput sequencing studies have identified recurrent mutations in key pathways, most notably NOTCH2 mutations in >25% of patients. These studies are based on small, heterogeneous discovery cohorts, and therefore only captured a fraction of the lesions present in the SMZL genome. To identify further novel pathogenic mutations within related biochemical pathways, we applied whole exome sequencing (WES) and copy number (CN) analysis to a biologically and clinically homogeneous cohort of seven SMZL patients with 7q abnormalities and IGHV1-2*04 gene usage. We identified 173 somatic non-silent variants, affecting 160 distinct genes. In additional to providing independent validation of the presence of mutation in several previously reported genes (NOTCH2, TNFAIP3, MAP3K14, MLL2 and SPEN), our study defined eight additional recurrently mutated genes in SMZL; these genes are CREBBP, CBFA2T3, AMOTL1, FAT4, FBXO11, PLA2G4D, TRRAP and USH2A. By integrating our WES and CN data we identified three mutated putative candidate genes targeted by 7q deletions (CUL1, EZH2 and FLNC), with FLNC positioned within the well-characterized 7q minimally deleted region. Taken together, this work expands the reported directory of recurrently mutated cancer genes in this disease, thereby expanding our understanding of SMZL pathogenesis. Ultimately, this work will help to establish a stratified approach to care including the possibility of targeted therapy. PMID:24349473

Ennis, Sarah; Walewska, Renata; Forster, Jade; Parker, Helen; Davis, Zadie; Gardiner, Anne; Collins, Andrew; Oscier, David G.; Strefford, Jonathan C.

2013-01-01

185

Whole exome sequencing identifies novel recurrently mutated genes in patients with splenic marginal zone lymphoma.  

PubMed

The pathogenesis of splenic marginal zone lymphoma (SMZL) remains largely unknown. Recent high-throughput sequencing studies have identified recurrent mutations in key pathways, most notably NOTCH2 mutations in >25% of patients. These studies are based on small, heterogeneous discovery cohorts, and therefore only captured a fraction of the lesions present in the SMZL genome. To identify further novel pathogenic mutations within related biochemical pathways, we applied whole exome sequencing (WES) and copy number (CN) analysis to a biologically and clinically homogeneous cohort of seven SMZL patients with 7q abnormalities and IGHV1-2*04 gene usage. We identified 173 somatic non-silent variants, affecting 160 distinct genes. In additional to providing independent validation of the presence of mutation in several previously reported genes (NOTCH2, TNFAIP3, MAP3K14, MLL2 and SPEN), our study defined eight additional recurrently mutated genes in SMZL; these genes are CREBBP, CBFA2T3, AMOTL1, FAT4, FBXO11, PLA2G4D, TRRAP and USH2A. By integrating our WES and CN data we identified three mutated putative candidate genes targeted by 7q deletions (CUL1, EZH2 and FLNC), with FLNC positioned within the well-characterized 7q minimally deleted region. Taken together, this work expands the reported directory of recurrently mutated cancer genes in this disease, thereby expanding our understanding of SMZL pathogenesis. Ultimately, this work will help to establish a stratified approach to care including the possibility of targeted therapy. PMID:24349473

Parry, Marina; Rose-Zerilli, Matthew J J; Gibson, Jane; Ennis, Sarah; Walewska, Renata; Forster, Jade; Parker, Helen; Davis, Zadie; Gardiner, Anne; Collins, Andrew; Oscier, David G; Strefford, Jonathan C

2013-01-01

186

Phenylalanine hydroxylase gene mutations in the United States: report from the Maternal PKU Collaborative Study.  

PubMed Central

The major cause of hyperphenylalaninemia is mutations in the gene encoding phenylalanine hydroxylase (PAH). The known mutations have been identified primarily in European patients. The purpose of this study was to determine the spectrum of mutations responsible for PAH deficiency in the United States. One hundred forty-nine patients enrolled in the Maternal PKU Collaborative Study were subjects for clinical and molecular investigations. PAH gene mutations associated with phenylketonuria (PKU) or mild hyperphenylalaninemia (MHP) were identified on 279 of 294 independent mutant chromosomes, a diagnostic efficiency of 95%. The spectrum is composed of 71 different mutations, including 47 missense mutations, 11 splice mutations, 5 nonsense mutations, and 8 microdeletions. Sixteen previously unreported mutations were identified. Among the novel mutations, five were found in patients with MHP, and the remainder were found in patients with PKU. The most common mutations were R408W, IVS12nt1g-->a, and Y414C, accounting for 18.7%, 7.8%, and 5.4% of the mutant chromosomes, respectively. Thirteen mutations had relative frequencies of 1%-5%, and 55 mutations each had frequencies < or = 1%. The mutational spectrum corresponded to that observed for the European ancestry of the U.S. population. To evaluate the extent of allelic variation at the PAH locus within the United States in comparison with other populations, we used allele frequencies to calculate the homozygosity for 11 populations where >90% ascertainment of mutations has been obtained. The United States was shown to contain one of the most heterogeneous populations, with homozygosity values similar to Sicily and ethnically mixed sample populations in Europe. The extent of allelic heterogeneity must be a major determining factor in the choice of mutation-detection methodology for molecular diagnosis in PAH deficiency. Images Figure 1 PMID:8659548

Guldberg, P.; Levy, H. L.; Hanley, W. B.; Koch, R.; Matalon, R.; Rouse, B. M.; Trefz, F.; de la Cruz, F.; Henriksen, K. F.; Güttler, F.

1996-01-01

187

EpilepsyGene: a genetic resource for genes and mutations related to epilepsy  

PubMed Central

Epilepsy is one of the most prevalent chronic neurological disorders, afflicting about 3.5–6.5 per 1000 children and 10.8 per 1000 elderly people. With intensive effort made during the last two decades, numerous genes and mutations have been published to be associated with the disease. An organized resource integrating and annotating the ever-increasing genetic data will be imperative to acquire a global view of the cutting-edge in epilepsy research. Herein, we developed EpilepsyGene (http://61.152.91.49/EpilepsyGene). It contains cumulative to date 499 genes and 3931 variants associated with 331 clinical phenotypes collected from 818 publications. Furthermore, in-depth data mining was performed to gain insights into the understanding of the data, including functional annotation, gene prioritization, functional analysis of prioritized genes and overlap analysis focusing on the comorbidity. An intuitive web interface to search and browse the diversified genetic data was also developed to facilitate access to the data of interest. In general, EpilepsyGene is designed to be a central genetic database to provide the research community substantial convenience to uncover the genetic basis of epilepsy. PMID:25324312

Ran, Xia; Li, Jinchen; Shao, Qianzhi; Chen, Huiqian; Lin, Zhongdong; Sun, Zhong Sheng; Wu, Jinyu

2015-01-01

188

Repeated Evolution of Chimeric Fusion Genes in the ?-Globin Gene Family of Laurasiatherian Mammals  

PubMed Central

The evolutionary fate of chimeric fusion genes may be strongly influenced by their recombinational mode of origin and the nature of functional divergence between the parental genes. In the ?-globin gene family of placental mammals, the two postnatally expressed ?- and ?-globin genes (HBD and HBB, respectively) have a propensity for recombinational exchange via gene conversion and unequal crossing-over. In the latter case, there are good reasons to expect differences in retention rates for the reciprocal HBB/HBD and HBD/HBB fusion genes due to thalassemia pathologies associated with the HBD/HBB “Lepore” deletion mutant in humans. Here, we report a comparative genomic analysis of the mammalian ?-globin gene cluster, which revealed that chimeric HBB/HBD fusion genes originated independently in four separate lineages of laurasiatherian mammals: Eulipotyphlans (shrews, moles, and hedgehogs), carnivores, microchiropteran bats, and cetaceans. In cases where an independently derived “anti-Lepore” duplication mutant has become fixed, the parental HBD and/or HBB genes have typically been inactivated or deleted, so that the newly created HBB/HBD fusion gene is primarily responsible for synthesizing the ?-type subunits of adult and fetal hemoglobin (Hb). Contrary to conventional wisdom that the HBD gene is a vestigial relict that is typically inactivated or expressed at negligible levels, we show that HBD-like genes often encode a substantial fraction (20–100%) of ?-chain Hbs in laurasiatherian taxa. Our results indicate that the ascendancy or resuscitation of genes with HBD-like coding sequence requires the secondary acquisition of HBB-like promoter sequence via unequal crossing-over or interparalog gene conversion. PMID:24814285

Gaudry, Michael J.; Storz, Jay F.; Butts, Gary Tyler; Campbell, Kevin L.; Hoffmann, Federico G.

2014-01-01

189

Repeated evolution of chimeric fusion genes in the ?-globin gene family of laurasiatherian mammals.  

PubMed

The evolutionary fate of chimeric fusion genes may be strongly influenced by their recombinational mode of origin and the nature of functional divergence between the parental genes. In the ?-globin gene family of placental mammals, the two postnatally expressed ?- and ?-globin genes (HBD and HBB, respectively) have a propensity for recombinational exchange via gene conversion and unequal crossing-over. In the latter case, there are good reasons to expect differences in retention rates for the reciprocal HBB/HBD and HBD/HBB fusion genes due to thalassemia pathologies associated with the HBD/HBB "Lepore" deletion mutant in humans. Here, we report a comparative genomic analysis of the mammalian ?-globin gene cluster, which revealed that chimeric HBB/HBD fusion genes originated independently in four separate lineages of laurasiatherian mammals: Eulipotyphlans (shrews, moles, and hedgehogs), carnivores, microchiropteran bats, and cetaceans. In cases where an independently derived "anti-Lepore" duplication mutant has become fixed, the parental HBD and/or HBB genes have typically been inactivated or deleted, so that the newly created HBB/HBD fusion gene is primarily responsible for synthesizing the ?-type subunits of adult and fetal hemoglobin (Hb). Contrary to conventional wisdom that the HBD gene is a vestigial relict that is typically inactivated or expressed at negligible levels, we show that HBD-like genes often encode a substantial fraction (20-100%) of ?-chain Hbs in laurasiatherian taxa. Our results indicate that the ascendancy or resuscitation of genes with HBD-like coding sequence requires the secondary acquisition of HBB-like promoter sequence via unequal crossing-over or interparalog gene conversion. PMID:24814285

Gaudry, Michael J; Storz, Jay F; Butts, Gary Tyler; Campbell, Kevin L; Hoffmann, Federico G

2014-05-01

190

Spectrum of MECP2 gene mutations in a cohort of Indian patients with Rett syndrome: report of two novel mutations.  

PubMed

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder, primarily affecting females and characterized by developmental regression, epilepsy, stereotypical hand movements, and motor abnormalities. Its prevalence is about 1 in 10,000 female births. Rett syndrome is caused by mutations within methyl CpG-binding protein 2 (MECP2) gene. Over 270 individual nucleotide changes which cause pathogenic mutations have been reported. However, eight most commonly occurring missense and nonsense mutations account for almost 70% of all patients. We screened 90 individuals with Rett syndrome phenotype. A total of 19 different MECP2 mutations and polymorphisms were identified in 27 patients. Of the 19 mutations, we identified 7 (37%) frameshift, 6 (31%) nonsense, 14 (74%) missense mutations and one duplication (5%). The most frequent pathogenic changes were: missense p.T158M (11%), p.R133C (7.4%), and p.R306C (7.4%) and nonsense p.R168X (11%), p.R255X (7.4%) mutations. We have identified two novel mutations namely p.385-388delPLPP present in atypical patients and p.Glu290AlafsX38 present in a classical patient of Rett syndrome. Sequence homology for p.385-388delPLPP mutation revealed that these 4 amino acids were conserved across mammalian species. This indicated the importance of these 4 amino acids in structure and function of the protein. A novel variant p.T479T has also been identified in a patient with atypical Rett syndrome. A total of 62 (69%) patients remained without molecular genetics diagnosis that necessitates further search for mutations in other genes like CDKL5 and FOXG1 that are known to cause Rett phenotype. The majority of mutations are detected in exon 4 and only one mutation was present in exon 3. Therefore, our study suggests the need for screening exon 4 of MECP2 as first line of diagnosis in these patients. PMID:23262346

Das, Dhanjit Kumar; Raha, Sarbani; Sanghavi, Daksha; Maitra, Anurupa; Udani, Vrajesh

2013-02-15

191

Interleukin-7 receptor-? gene mutations are not detected in adult T-cell acute lymphoblastic leukemia.  

PubMed

Somatic mutations in cancer cell genes are classified according to their functional significance. Those that provide the malignant cells with significant advantage are collectively referred to as driver mutations and those that do not, are the passenger mutations. Accordingly, analytical criteria to distinguish driver mutations from passenger mutations have been recently suggested. Recent studies revealed mutations in interleukin-7 receptor-? (IL7R) gene in 10% of pediatric T-cell acute lymphoblastic leukemia (T-ALL) patients and in only a few cases of pediatric B-ALL. IL7R mutations are also frequently found in patients with lung cancer, but whereas in pediatric T-ALL IL7R mutations are "drivers" (consisting of gain-of-function mutations within a narrow 50-base pair interval at exon 6 that confer cytokine-independent cell growth and promote tumor transformation), in lung cancer, mutations are substitution mutations randomly distributed across the gene and are probably only "passenger" events. Because the treatment response of adult T-ALL is significantly poorer than that of childhood T-ALL and because exon 6 IL7R mutations play a role in the pathogenesis of childhood T-ALL, we sought to determine how the pattern of IL7R mutations varies between adult and childhood T-ALL. To that end, we sequenced the 50-base pair interval in exon 6 of the IL7R of DNA obtained from bone marrow samples of 35 randomly selected adult patients with T-ALL. Our analysis revealed that none of these 35 samples carried an IL7R mutation in exon 6. Whether differences in the genetic makeup of adult and childhood T-ALL explain the differential response to therapy remains to be determined. PMID:24678068

Rozovski, Uri; Li, Ping; Harris, David; Ohanian, Maro; Kantarjian, Hagop; Estrov, Zeev

2014-06-01

192

Overview of Cytochrome P450 1B1 gene mutations in patients with primary congenital glaucoma.  

PubMed

The objective of this study was to investigate the distribution of mutations in the Cytochrome P450 1B1 gene (CYP1B1) in patients with primary congenital glaucoma (PCG) among different populations. All identifiable original studies on CYP1B1 gene mutations of patients with PCG were reviewed. Finally, DNA mutations within the CYP1B1 gene were identified in 542 patients with PCG according to 52 scientific articles and 147 distinct mutations were found. The 3987G>A (G61E) missense mutation is a founder mutation in Middle Eastern population, responsible for 45.52% of CYP1B1 mutations. In Gypsies, missense mutation 7996G>A (E387K) seems to be a founder mutation, accounting for 79.63% of CYP1B1 mutations. It seems that there is no founder mutation in Asian or Caucasian population, but also accumulates in some spots. Mutations 7927G>A (V364M), 7990C>T (L385F) and 8006G>A (R390H) are common in Asian population. In Caucasians, 7940G>A (R368H), 8037dup10, 8006G>A (R390H), 7901del13, 4340delG, 3987G>A (G61E), 7996G>A (E387K), 4490G>A (E229K) and 8005C>T/A (R390C/S) are common mutations. The findings suggest that ethnic differences and the geographical distribution of PCG may be associated with different CYP1B1 mutation patterns. Such information may be useful in developing strategies for reliable clinical genetic testing of patients with PCG and their families. PMID:21854771

Li, Ni; Zhou, Yong; Du, Liang; Wei, Maoling; Chen, Xiaoming

2011-11-01

193

A compound heterozygous mutation in the BSND gene detected in Bartter syndrome type IV.  

PubMed

Bartter syndrome is a genetic disorder with hypokalemic metabolic alkalosis and is classified into five types. Type IV Bartter syndrome is a type of neonatal Bartter syndrome with sensorineural deafness and has been recently shown to be caused by mutations in the BSND gene. Owing to the rarity of this disease, only a limited number of mutations have been reported. We analyzed the BSND gene in a patient with type IV Bartter syndrome. The patient was delivered at 37 weeks, with normal body weight, and his neonatal course was uneventful. He was examined for developmental delay and polyuria at age 1 year 8 months and was found to have hypokalemia, metabolic alkalosis, hyperreninemic hyperaldosteronism, and sensorineural deafness. He developed end-stage renal failure at age 15 years, and renal transplantation was performed. We identified compound heterozygous mutations (Q32X and G47R) in the BSND gene. Each mutation was inherited from the parents. The Q32X mutation is a novel mutation and the first nonsense mutation identified in this gene. The mild perinatal clinical features of the patient were similar to those of a patient reported with a homozygous G47R mutation. However, the severity of renal failure suggested that factors other than this gene might affect the manifestation of renal abnormalities. PMID:16328537

Kitanaka, Sachiko; Sato, Utako; Maruyama, Kenichi; Igarashi, Takashi

2006-02-01

194

Mutation analysis of BRCA1 gene in African-American patients with breast cancer.  

PubMed Central

An estimated 7% of all breast cancers and 10% of all ovarian cancers are associated with inherited mutations in BRCA1 and BRCA2 genes. The mutations of a breast cancer-susceptible gene, BRCA1, confers increased risk of breast cancer in young women. Numerous studies have reported specific mutations in the BRCA1 and BRCA2 genes in the white population. However, there are very few studies on African-American and other ethnic minority groups. The goal of this study is to identify whether African-American patients with breast cancer carry some common mutations reported in other ethnic groups and whether they carry some novel mutations. We screened hot-region mutations on exons 2, 5, 11, 16, and 20 of BRCA1 gene in 54 African-American patients with breast cancer by NIRCA and SSCP methods. Our data revealed one novel frameshift mutation (3331 insG) and three missense sequence variants (A3537G, A3667G, and C4009T) on exon 11. Each sequence change was confirmed by automatic DNA sequencing. One rare sequence variant, A3537G, has been revealed in high frequency (3/54). Our data suggested that African-American patients with breast cancer carry some unique BRCA1 gene mutations. Images Figure 1 Figure 2 PMID:10800284

Shen, D.; Wu, Y.; Subbarao, M.; Bhat, H.; Chillar, R.; Vadgama, J. V.

2000-01-01

195

A novel mutation in the calcium channel gene in a family with hypokalemic periodic paralysis.  

PubMed

Hypokalemic periodic paralysis (HypoPP) type 1 is an autosomal dominant disease caused by mutations in the Ca(V)1.1 calcium channel encoded by the CACNA1S gene. Only seven mutations have been found since the discovery of the causative gene in 1994. We describe a patient with HypoPP who had a high serum potassium concentration after recovery from a recent paralysis, which complicated the correct diagnosis. This patient and other affected family members had a novel mutation, p.Arg900Gly, in the CACNA1S gene. PMID:21855088

Hirano, Makito; Kokunai, Yosuke; Nagai, Asami; Nakamura, Yusaku; Saigoh, Kazumasa; Kusunoki, Susumu; Takahashi, Masanori P

2011-10-15

196

Clinical Significance of a Point Mutation in DNA Polymerase Beta (POLB) Gene in Gastric Cancer  

PubMed Central

Gastric cancer (GC) is a major cause of global cancer mortality. Genetic variations in DNA repair genes can modulate DNA repair capability and, consequently, have been associated with risk of developing cancer. We have previously identified a T to C point mutation at nucleotide 889 (T889C) in DNA polymerase beta (POLB) gene, a key enzyme involved in base excision repair in primary GCs. The purpose of this study was to evaluate the mutation and expression of POLB in a larger cohort and to identify possible prognostic roles of the POLB alterations in GC. Primary GC specimens and their matched normal adjacent tissues were collected at the time of surgery. DNA, RNA and protein samples were isolated from GC specimens and cell lines. Mutations were detected by PCR-RFLP/DHPLC and sequencing analysis. POLB gene expression was examined by RT-PCR, tissue microarray, Western blotting and immunofluorescence assays. The function of the mutation was evaluated by chemosensitivity, MTT, Transwell matrigel invasion and host cell reactivation assays. The T889C mutation was detected in 18 (10.17%) of 177 GC patients. And the T889C mutation was associated with POLB overexpression, lymph nodes metastases and poor tumor differentiation. In addition, patients with- the mutation had significantly shorter survival time than those without-, following postoperative chemotherapy. Furthermore, cell lines with T889C mutation in POLB gene were more resistant to the treatment of 5-fluorouracil, cisplatin and epirubicin than those with wild type POLB. Forced expression of POLB gene with T889C mutation resulted in enhanced cell proliferation, invasion and resistance to anticancer drugs, along with increased DNA repair capability. These results suggest that POLB gene with T889C mutation in surgically resected primary gastric tissues may be clinically useful for predicting responsiveness to chemotherapy in patients with GC. The POLB gene alteration may serve as a prognostic biomarker for GC. PMID:25561897

Tan, Xiaohui; Wang, Hongyi; Luo, Guangbin; Ren, Shuyang; Li, Wenmei; Cui, Jiantao; Gill, Harindarpal S.; Fu, Sidney W.; Lu, Youyong

2015-01-01

197

Clinical significance of a point mutation in DNA polymerase beta (POLB) gene in gastric cancer.  

PubMed

Gastric cancer (GC) is a major cause of global cancer mortality. Genetic variations in DNA repair genes can modulate DNA repair capability and, consequently, have been associated with risk of developing cancer. We have previously identified a T to C point mutation at nucleotide 889 (T889C) in DNA polymerase beta (POLB) gene, a key enzyme involved in base excision repair in primary GCs. The purpose of this study was to evaluate the mutation and expression of POLB in a larger cohort and to identify possible prognostic roles of the POLB alterations in GC. Primary GC specimens and their matched normal adjacent tissues were collected at the time of surgery. DNA, RNA and protein samples were isolated from GC specimens and cell lines. Mutations were detected by PCR-RFLP/DHPLC and sequencing analysis. POLB gene expression was examined by RT-PCR, tissue microarray, Western blotting and immunofluorescence assays. The function of the mutation was evaluated by chemosensitivity, MTT, Transwell matrigel invasion and host cell reactivation assays. The T889C mutation was detected in 18 (10.17%) of 177 GC patients. And the T889C mutation was associated with POLB overexpression, lymph nodes metastases and poor tumor differentiation. In addition, patients with- the mutation had significantly shorter survival time than those without-, following postoperative chemotherapy. Furthermore, cell lines with T889C mutation in POLB gene were more resistant to the treatment of 5-fluorouracil, cisplatin and epirubicin than those with wild type POLB. Forced expression of POLB gene with T889C mutation resulted in enhanced cell proliferation, invasion and resistance to anticancer drugs, along with increased DNA repair capability. These results suggest that POLB gene with T889C mutation in surgically resected primary gastric tissues may be clinically useful for predicting responsiveness to chemotherapy in patients with GC. The POLB gene alteration may serve as a prognostic biomarker for GC. PMID:25561897

Tan, Xiaohui; Wang, Hongyi; Luo, Guangbin; Ren, Shuyang; Li, Wenmei; Cui, Jiantao; Gill, Harindarpal S; Fu, Sidney W; Lu, Youyong

2015-01-01

198

Recurrent de novo mutations implicate novel genes underlying simplex autism risk.  

PubMed

Autism spectrum disorder (ASD) has a strong but complex genetic component. Here we report on the resequencing of 64 candidate neurodevelopmental disorder risk genes in 5,979 individuals: 3,486 probands and 2,493 unaffected siblings. We find a strong burden of de novo point mutations for these genes and specifically implicate nine genes. These include CHD2 and SYNGAP1, genes previously reported in related disorders, and novel genes TRIP12 and PAX5. We also show that mutation carriers generally have lower IQs and enrichment for seizures. These data begin to distinguish genetically distinct subtypes of autism important for aetiological classification and future therapeutics. PMID:25418537

O'Roak, B J; Stessman, H A; Boyle, E A; Witherspoon, K T; Martin, B; Lee, C; Vives, L; Baker, C; Hiatt, J B; Nickerson, D A; Bernier, R; Shendure, J; Eichler, E E

2014-01-01

199

Prevalence of Mutations in eyeGENE Probands With a Diagnosis of Autosomal Dominant Retinitis Pigmentosa  

PubMed Central

Purpose. To screen samples from patients with presumed autosomal dominant retinitis pigmentosa (adRP) for mutations in 12 disease genes as a contribution to the research and treatment goals of the National Ophthalmic Disease Genotyping and Phenotyping Network (eyeGENE). Methods. DNA samples were obtained from eyeGENE. A total of 170 probands with an intake diagnosis of adRP were tested through enrollment in eyeGENE. The 10 most common genes causing adRP (IMPDH1, KLHL7, NR2E3, PRPF3/RP18, PRPF31/RP11, PRPF8/RP13, PRPH2/RDS, RHO, RP1, and TOPORS) were chosen for PCR-based dideoxy sequencing, along with the two X-linked RP genes, RPGR and RP2. RHO, PRPH2, PRPF31, RPGR, and RP2 were completely sequenced, while only mutation hotspots in the other genes were analyzed. Results. Disease-causing mutations were identified in 52% of the probands. The frequencies of disease-causing mutations in the 12 genes were consistent with previous studies. Conclusions. The Laboratory for Molecular Diagnosis of Inherited Eye Disease at the University of Texas in Houston has thus far received DNA samples from 170 families with a diagnosis of adRP from the eyeGENE Network. Disease-causing mutations in autosomal genes were identified in 48% (81/170) of these families while mutations in X-linked genes accounted for an additional 4% (7/170). Of the 55 distinct mutations detected, 19 (33%) have not been previously reported. All diagnostic results were returned by eyeGENE to participating patients via their referring clinician. These genotyped samples along with their corresponding phenotypic information are also available to researchers who may request access to them for further study of these ophthalmic disorders. (ClinicalTrials.gov number, NCT00378742.) PMID:23950152

Sullivan, Lori S.; Bowne, Sara J.; Reeves, Melissa J.; Blain, Delphine; Goetz, Kerry; NDifor, Vida; Vitez, Sally; Wang, Xinjing; Tumminia, Santa J.; Daiger, Stephen P.

2013-01-01

200

Mutations in the EXT1 and EXT2 genes in Spanish patients with multiple osteochondromas  

PubMed Central

Multiple osteochondromas is an autosomal dominant skeletal disorder characterized by the formation of multiple cartilage-capped tumours. Two causal genes have been identified, EXT1 and EXT2, which account for 65% and 30% of cases, respectively. We have undertaken a mutation analysis of the EXT1 and EXT2 genes in 39 unrelated Spanish patients, most of them with moderate phenotype, and looked for genotype-phenotype correlations. We found the mutant allele in 37 patients, 29 in EXT1 and 8 in EXT2. Five of the EXT1 mutations were deletions identified by MLPA. Two cases of mosaicism were documented. We detected a lower number of exostoses in patients with missense mutation versus other kinds of mutations. In conclusion, we found a mutation in EXT1 or in EXT2 in 95% of the Spanish patients. Eighteen of the mutations were novel. PMID:23439489

Sarrión, P.; Sangorrin, A.; Urreizti, R.; Delgado, A.; Artuch, R.; Martorell, L.; Armstrong, J.; Anton, J.; Torner, F.; Vilaseca, M. A.; Nevado, J.; Lapunzina, P.; Asteggiano, C. G.; Balcells, S.; Grinberg, D.

2013-01-01

201

A novel missense mutation in the Connexin 26 gene associated with autosomal recessive sensorineural deafness.  

PubMed

Mutations in the Connexin 26 (Cx26) gene (GJB2) are a common cause of hereditary hearing impairment. We report the identification of a novel point mutation in the Cx26 gene, Leu205Pro(L205P), linked to familial, autosomal recessive sensorineural hearing loss. This missense mutation, causing amino acid leucine at position 205 to be substituted by proline, is located in the highly conserved sequence of the fourth transmembrane domain (TM4) of Cx26. Hearing loss with this mutation occurred in a Georgian Jewish family, was congenital, moderate to profound and nonprogressive. We have shown that the new mutation L205P in Cx26 is strongly associated with congenital NSHL. Multiple-sample screening for this mutation can be easily performed with a mismatch PCR that creates a restriction site. PMID:15811717

Leshinsky-Silver, E; Berman, Z; Vinkler, C; Yannov-Sharav, M; Lev, D

2005-04-01

202

KMeyeDB: a graphical database of mutations in genes that cause eye diseases.  

PubMed

KMeyeDB (http://mutview.dmb.med.keio.ac.jp/) is a database of human gene mutations that cause eye diseases. We have substantially enriched the amount of data in the database, which now contains information about the mutations of 167 human genes causing eye-related diseases including retinitis pigmentosa, cone-rod dystrophy, night blindness, Oguchi disease, Stargardt disease, macular degeneration, Leber congenital amaurosis, corneal dystrophy, cataract, glaucoma, retinoblastoma, Bardet-Biedl syndrome, and Usher syndrome. KMeyeDB is operated using the database software MutationView, which deals with various characters of mutations, gene structure, protein functional domains, and polymerase chain reaction (PCR) primers, as well as clinical data for each case. Users can access the database using an ordinary Internet browser with smooth user-interface, without user registration. The results are displayed on the graphical windows together with statistical calculations. All mutations and associated data have been collected from published articles. Careful data analysis with KMeyeDB revealed many interesting features regarding the mutations in 167 genes that cause 326 different types of eye diseases. Some genes are involved in multiple types of eye diseases, whereas several eye diseases are caused by different mutations in one gene. PMID:20232414

Kawamura, Takashi; Ohtsubo, Masafumi; Mitsuyama, Susumu; Ohno-Nakamura, Saho; Shimizu, Nobuyoshi; Minoshima, Shinsei

2010-06-01

203

DNA repair genes are selectively mutated in diffuse large B cell lymphomas  

PubMed Central

DNA repair mechanisms are fundamental for B cell development, which relies on the somatic diversification of the immunoglobulin genes by V(D)J recombination, somatic hypermutation, and class switch recombination. Their failure is postulated to promote genomic instability and malignant transformation in B cells. By performing targeted sequencing of 73 key DNA repair genes in 29 B cell lymphoma samples, somatic and germline mutations were identified in various DNA repair pathways, mainly in diffuse large B cell lymphomas (DLBCLs). Mutations in mismatch repair genes (EXO1, MSH2, and MSH6) were associated with microsatellite instability, increased number of somatic insertions/deletions, and altered mutation signatures in tumors. Somatic mutations in nonhomologous end-joining (NHEJ) genes (DCLRE1C/ARTEMIS, PRKDC/DNA-PKcs, XRCC5/KU80, and XRCC6/KU70) were identified in four DLBCL tumors and cytogenetic analyses revealed that translocations involving the immunoglobulin-heavy chain locus occurred exclusively in NHEJ-mutated samples. The novel mutation targets, CHEK2 and PARP1, were further screened in expanded DLBCL cohorts, and somatic as well as novel and rare germline mutations were identified in 8 and 5% of analyzed tumors, respectively. By correlating defects in a subset of DNA damage response and repair genes with genomic instability events in tumors, we propose that these genes play a role in DLBCL lymphomagenesis. PMID:23960188

de Miranda, Noel FCC; Peng, Roujun; Georgiou, Konstantinos; Wu, Chenglin; Sörqvist, Elin Falk; Berglund, Mattias; Chen, Longyun; Gao, Zhibo; Lagerstedt, Kristina; Lisboa, Susana; Roos, Fredrik; van Wezel, Tom; Teixeira, Manuel R.; Rosenquist, Richard; Sundström, Christer; Enblad, Gunilla; Nilsson, Mats; Zeng, Yixin; Kipling, David

2013-01-01

204

CFTR Gene Mutations and Asthma in Indian Children: A Case-Control Study.  

PubMed

Cystic Fibrosis Trans membrane conductance regulator (CFTR) gene is an asthma susceptibility gene. In the present study we investigated the possible association of CFTR gene mutations in Indian asthmatic children as compared to controls. The study included 250 asthmatics and 250 age and sex matched controls. Case to control ratio for sample size was 1:1. Genotyping was performed for 24 CFTR gene mutations by ARMS-PCR and PCR-RFLP method. Among 24 CFTR gene mutations, heterozygous allele of R553X mutation was found in 4 (1.6 %) asthmatic cases and 2 (0.8 %) controls. Value of FVC and FEV1/FVC ratio were significantly lower in heterozygous individuals (p value <0.05). No significant difference was observed in the genotype and allele frequency of R553X mutation (OR = 1.339, 95?% CI = 0.755-2.374, p value = 0.685). Furthermore, all wild type homozygous alleles were observed in remaining 23 CFTR gene mutations. Our data concludes that R553X mutation was not significantly associated in Indian asthmatic children. PMID:25646039

Dixit, Pratibha; Awasthi, Shally; Maurya, Nutan; Agarwal, Sarita; Srinivasan, M

2015-01-01

205

Hybrid curation of gene–mutation relations combining automated extraction and crowdsourcing  

PubMed Central

Background: This article describes capture of biological information using a hybrid approach that combines natural language processing to extract biological entities and crowdsourcing with annotators recruited via Amazon Mechanical Turk to judge correctness of candidate biological relations. These techniques were applied to extract gene– mutation relations from biomedical abstracts with the goal of supporting production scale capture of gene–mutation–disease findings as an open source resource for personalized medicine. Results: The hybrid system could be configured to provide good performance for gene–mutation extraction (precision ?82%; recall ?70% against an expert-generated gold standard) at a cost of $0.76 per abstract. This demonstrates that crowd labor platforms such as Amazon Mechanical Turk can be used to recruit quality annotators, even in an application requiring subject matter expertise; aggregated Turker judgments for gene–mutation relations exceeded 90% accuracy. Over half of the precision errors were due to mismatches against the gold standard hidden from annotator view (e.g. incorrect EntrezGene identifier or incorrect mutation position extracted), or incomplete task instructions (e.g. the need to exclude nonhuman mutations). Conclusions: The hybrid curation model provides a readily scalable cost-effective approach to curation, particularly if coupled with expert human review to filter precision errors. We plan to generalize the framework and make it available as open source software. Database URL: http://www.mitre.org/publications/technical-papers/hybrid-curation-of-gene-mutation-relations-combining-automated PMID:25246425

Burger, John D.; Doughty, Emily; Khare, Ritu; Wei, Chih-Hsuan; Mishra, Rajashree; Aberdeen, John; Tresner-Kirsch, David; Wellner, Ben; Kann, Maricel G.; Lu, Zhiyong; Hirschman, Lynette

2014-01-01

206

Campomelic dysplasia and autosomal sex reversal caused by mutations in an SRY-related gene  

Microsoft Academic Search

Induction of testis development in mammals requires the presence of the Y-chromosome gene SPY. This gene must exert its effect by interacting with other genes in the sex-determination pathway. Cloning of a translocation chromosome breakpoint from a sex-reversed patient with campomelic dysplasia, followed by mutation analysis of an adjacent gene, indicates that SOX9, an SRY-related gene, is involved in both

Jamie W. Foster; Marina A. Dominguez-Steglich; Silvana Guioli; Cheni Kwok; Polly A. Weller; Milena Stevanovic; Jean Weissenbach; Sahar Mansour; Ian D. Young; Peter N. Goodfellow; J. David Brook; Alan J. Schafer

1994-01-01

207

[Aged onset of amyloidosis caused by transthyretin gene mutations].  

PubMed

We have identified that familial amyloid polyneuropathy with middle age onset results from missense mutations of the transthyretin gene. In the present study, we investigated molecular abnormalities of transthyretin in elderly patients with cardiac amyloidosis or amyloid polyneuropathy, using DNA sequencing and protein sequencing. We detected 5 cases of transthyretin-related cardiac amyloidosis using immunohistochemical techniques. All of them had late-onset, mild or no peripheral neuropathy or autonomic dysfunctions, and no family history. Three had transthyretin Met30 and two transthyretin Ile50. We also found 15 patients with transthyretin-related amyloid polyneuropathy. All of them had late-onset and no contributory family history. Twelve had transthyretin Met30, two transthyretin Ile50, and one transthyretin Ser109. Clinical manifestations and sequencing procedures of six representative patients were also presented. Molecular investigation of transthyretin is needed for elderly patients with etiology-unknown cardiac amyloidosis or amyloid polyneuropathy even if there is no family history of amyloidosis. PMID:11523162

Nakazato, M; Matsukura, S

2001-07-01

208

Interacting genes that affect microtubule function in Drosophila melanogaster: Two classes of mutation revert the failure to complement between hay sup nc2 and mutations in tubulin genes  

SciTech Connect

The recessive male sterile mutation hay{sup nc2} of Drosophila melanogaster fails to complement certain {beta}{sub 2}-tubulin and {alpha}-tubulin mutations, suggesting that the haywire product plays a role in microtubule function, perhaps as a structural component of microtubules. The genetic interaction appears to require the presence of the aberrant product encoded by hay{sup nc2}, which may act as a structural poison. Based on this observation, the authors have isolated ten new mutations with EMS that revert the failure to complement between hay{sup nc2} and B2t{sup n}. The revertants tested behaved as intragenic mutations of hay in recombination tests, and feel into two phenotypic classes, suggesting two functional domains of the hay gene product. Some revertants were hemizygous viable and less severe than hay{sup nc2} in their recessive phenotype. These mutations might revert the poison by restoring the aberrant product encoded by the hay{sup nc2} allele to more wild-type function. Most of the revertants were recessive lethal mutations, indicating that the hay gene product is essential for viability. These more extreme mutations could revert the poison by destroying the ability of the aberrant haywire{sup nc2} product to interact structurally with microtubules. Flies heterozygous for the original hay{sup nc2} allele and an extreme revertant show defects in both the structure and the function of the male meiotic spindle.

Regan, C.L.; Fuller, M.T. (Univ. of Colorado, Boulder (USA))

1990-05-01

209

Genomic analyses of gynaecologic carcinosarcomas reveal frequent mutations in chromatin remodelling genes  

PubMed Central

Malignant mixed Müllerian tumours, also known as carcinosarcomas, are rare tumours of gynaecological origin. Here we perform whole-exome analyses of 22 tumours using massively parallel sequencing to determine the mutational landscape of this tumour type. On average, we identify 43 mutations per tumour, excluding four cases with a mutator phenotype that harboured inactivating mutations in mismatch repair genes. In addition to mutations in TP53 and KRAS, we identify genetic alterations in chromatin remodelling genes, ARID1A and ARID1B, in histone methyltransferase MLL3, in histone deacetylase modifier SPOP and in chromatin assembly factor BAZ1A, in nearly two thirds of cases. Alterations in genes with potential clinical utility are observed in more than three quarters of the cases and included members of the PI3-kinase and homologous DNA repair pathways. These findings highlight the importance of the dysregulation of chromatin remodelling in carcinosarcoma tumorigenesis and suggest new avenues for personalized therapy. PMID:25233892

Jones, Siân; Stransky, Nicolas; McCord, Christine L.; Cerami, Ethan; Lagowski, James; Kelly, Devon; Angiuoli, Samuel V.; Sausen, Mark; Kann, Lisa; Shukla, Manish; Makar, Rosemary; Wood, Laura D.; Diaz, Luis A.; Lengauer, Christoph; Velculescu, Victor E.

2015-01-01

210

Novel mutations in the sacsin gene in ataxia patients from Maritime Canada.  

PubMed

We ascertained two families in Eastern Canada segregating a form of ataxia consistent with a recessive mode of inheritance. We performed a whole genome scan using dense SNP genotyping, and despite an absence of shared homozygosity in the families we defined linkage to a small region on chromosome 13. Direct DNA resequencing was employed to screen biologically relevant candidate genes in the interval, and two presumptive pathogenic mutations were found in the gene encoding sacsin. One variant is an obligate truncating mutation, the second is a missense variant in a highly conserved residue. Unexpectedly, one family was homozygous for the missense mutation, the other compound heterozygous for the two mutations. Our results expand the genotype phenotype correlation of mutations in the sacsin gene, and highlight the challenge of diagnosing genetically heterogeneous disorders on primarily clinical grounds. We demonstrate that whole genome genotyping on a modest scale can be productive in research, and potentially in a clinical context. PMID:19892370

Guernsey, D L; Dubé, M-P; Jiang, H; Asselin, G; Blowers, S; Evans, S; Ferguson, M; Macgillivray, C; Matsuoka, M; Nightingale, M; Rideout, A; Delatycki, M; Orr, A; Ludman, M; Dooley, J; Riddell, C; Samuels, M E

2010-01-15

211

Mutations in the SLC3A1 transporter gene in cystinuria  

SciTech Connect

Cystinuria is an autosomal recessive disease characterized by the development of kidney stones. Guided by the identification of the SLC3A1 amino acid-transport gene on chromosome 2, we recently established genetic linkage of cystinuria to chromosome 2p in 17 families, without evidence for locus heterogeneity. Other authors have independently identified missense mutations in SLC3A1 in cystinuria patients. In this report we describe four additional cystinuria-associated mutations in this gene: a frameshift, a deletion, a transversion inducing a critical amino acid change, and a nonsense mutation. The latter stop codon was found in all of eight Ashkenazi Jewish carrier chromosomes examined. This report brings the number of disease-associated mutations in this gene to 10. We also assess the frequency of these mutations in our 17 cystinuria families. 24 refs., 4 figs., 1 tab.

Pras, E.; Raben, N.; Aksentijevich, I. [National Heart, Lung, and Blood Institute, Bethesda, MD (United States)] [and others

1995-06-01

212

High Frequency of Mutations of the PIK3CA Gene in Human Cancers  

E-print Network

High Frequency of Mutations of the PIK3CA Gene in Human Cancers Yardena Samuels,1 Zhenghe Wang,1 in 35 colorectal cancers (3). PIK3CA, which encodes the p110 catalytic subunit, was the only gene (1­3). To determine if PI3Ks are genetically altered in tumorigenesis, we se- quenced PI3K genes

Gleeson, Joseph G.

213

CLINICAL STUDY Mutational analysis of the necdin gene in patients with  

E-print Network

candidate loci for IHH include genes with potential influence on GNRH neuron migration, secretion, or actionCLINICAL STUDY Mutational analysis of the necdin gene in patients with congenital isolated Claudia Latronico Unidade de Endocrinologia do Desenvolvimento, Laborato´rio de Hormo^nios e Gene

Mellon, Pamela L.

214

Characterization of a Spontaneous, Recessive, Missense Mutation Arising in the Tecta Gene  

Microsoft Academic Search

The TECTA gene encodes alpha-tectorin (TECTA), a major noncollagenous component of the tectorial membrane (TM). In humans, mutations\\u000a in TECTA lead to either dominant (DFNA8\\/A12) or recessive (DFNB21) forms of nonsyndromic hearing loss. All missense mutations in TECTA that have been reported thus far are associated with the dominant subtype, whereas those leading to recessive deafness are\\u000a all inactivating mutations.

Miguel Ángel Moreno-Pelayo; Richard J. Goodyear; Angeles Mencía; Silvia Modamio-Hřybjřr; P. Kevin Legan; Leticia Olavarrieta; Felipe Moreno; Guy P. Richardson

2008-01-01

215

Novel mutations in the CDKL5 gene, predicted effects and associated phenotypes  

Microsoft Academic Search

It has been found that CDKL5 gene mutations are responsible for early-onset epilepsy and drug resistance. We screened a population\\u000a of 92 patients with classic\\/atypical Rett syndrome, 17 Angelman\\/Angelman-like patients and six idiopathic autistic patients\\u000a for CDKL5 mutations and exon deletions and identified seven novel mutations: six in the Rett subset and one in an Angelman\\u000a patient. This last, an

S. Russo; M. Marchi; F. Cogliati; M. T. Bonati; M. Pintaudi; E. Veneselli; V. Saletti; M. Balestrini; B. Ben-Zeev; L. Larizza

2009-01-01

216

Somatic Mutations of the Protein Kinase Gene Family in Human Lung Cancer  

Microsoft Academic Search

Protein kinases are frequently mutated in human cancer and inhibitors of mutant protein kinases have proven to be effective anticancer drugs. We screened the coding sequences of 518 protein kinases (f1.3 Mb of DNA per sample) for somatic mutations in 26 primary lung neoplasms and seven lung cancer cell lines. One hundred eighty-eight somatic mutations were detected in 141 genes.

Helen Davies; Chris Hunter; Raffaella Smith; Philip Stephens; Chris Greenman; Graham Bignell; Jon Teague; Adam Butler; Sarah Edkins; Claire Stevens; Adrian Parker; Sarah O'Meara; Syd Barthorpe; Lisa Brackenbury; Jody Clements; Jennifer Cole; Ed Dicks; Ken Edwards; Simon Forbes; Matthew Gorton; Kristian Gray; Kelly Halliday; Rachel Harrison; Katy Hills; Jonathon Hinton; David Jones; Vivienne Kosmidou; Ross Laman; Richard Lugg; Andrew Menzies; Janet Perry; Robert Petty; Keiran Raine; Rebecca Shepherd; Alexandra Small; Helen Solomon; Yvonne Stephens; Calli Tofts; Jennifer Varian; Anthony Webb; Sofie West; Sara Widaa; Andrew Yates; Francis Brasseur; Colin S. Cooper; Adrienne M. Flanagan; Anthony Green; Maggie Knowles; Suet Y. Leung; Leendert H. J. Looijenga; Bruce Malkowicz; Marco A. Pierotti; Siu T. Yuen; Sunil R. Lakhani; Douglas F. Easton; Barbara L. Weber; Peter Goldstraw; Andrew G. Nicholson; Richard Wooster; Michael R. Stratton; P. Andrew Futreal

2005-01-01

217

UV and Skin Cancer: Specific p53 Gene Mutation in Normal Skin as a Biologically Relevant Exposure Measurement  

Microsoft Academic Search

Many human skin tumors contain mutated p53 genes that probably result from UV exposure. To investigate the link between UV exposure and p53 gene mutation, we developed two methods to detect presumptive UV-specific p53 gene mutations in UV-exposed normal skin. The methods are based on mutant allele-specific PCRs and ligase chain reactions and designed to detect CC to TT mutations

Hisayoshi Nakazawa; Dallas English; Peter L. Randell; Keiko Nakazawa; Nicole Martel; Bruce K. Armstrong; Hiroshi Yamasaki

1994-01-01

218

Consequences of Marfan mutations to expression of fibrillin gene and to the structure of microfibrils  

SciTech Connect

Marfan syndrome (MFS) is a dominantly inherited connective tissue disorder which is caused by mutations in the fibrillin-1 gene (FBN1). Over 40 family-specific FBN1 mutations have been identified. We have characterized 18 different heterozygous mutations including amino acid substitutions, premature stop, and splicing defects leading to deletions or one insertion, and one compound heterozygote with two differently mutated FBN1 alleles inherited from his affected parents. To unravel the consequences of FBN1 mutations to the transcription of FBN1 gene, we have measured the steady state levels of mRNA transcribed from the normal and mutated alleles. The missense mutations do not affect the transcription of the allele while the nonsense mutation leads to lower steady state amount of mutated allele. For the dissection of molecular pathogenesis of FBN1 mutations we have performed rotary shadowing of the microfibrils produced by the cell cultures from MFS patients. The cells from the neonatal patients with established mutations produced only disorganized fibrillin aggregates but no clearly defined microfibrils could be detected, suggesting a major role of this gene region coding for exons 24-26 in stabilization and organization of the bead structure of microfibrils. From the cells of a rare compound heterozygote case carrying two different mutations, no detectable microfibrils could be detected whereas the cells of his parents with heterozygous mutations were able to form identifiable but disorganized microfibrils. In the cells of an MFS case caused by a premature stop removing the C-terminus of fibrillin, the microfibril assembly takes place but the appropriate packing of the microfibrils is disturbed suggesting that C-terminae are actually located within the interbead domain of the microfibrils.

Peltonen, L.; Karttunen, L.; Rantamaeki, T. [NPHI, Helsinki (Finland)] [and others

1994-09-01

219

Characterization of phenylalanine hydroxylase gene mutations in phenylketonuria in Xinjiang of China  

PubMed Central

To investigate the spectrum and frequency of phenylalanine hydroxylase (PAH) gene mutations in phenylketonuria (PKU) patients in Xinjiang, China. Polymerase chain reaction (PCR), in combination with single-strand conformation polymorphism (SSCP) and DNA sequencing analyses were performed, to screen potential mutations in the PAH gene in 46 individual PKU patients. Direct DNA sequencing was used to analyze the all of the exons in the PAH gene, including the promoter and flanking intron regions, in another 15 PKU patients. Our results indicated that, 30 different mutation types were identified in all 122 PAH alleles, with the mutation detection rate of 78.7% (96/122). Four novel mutations, i.e., 5’-Flanking -626G>A, 5’-Flanking -480DelACT, S196fsX4, and IVS8+1G>C, were identified for the first time. Similar to other regions in North China, R243Q, EX6-96A>G, IVS4-1A>G, R111X, and Y356X were the most prevalent PAH mutations in PKU patients from Xinjiang. Additionally, common mutations showed different frequencies in Xinjiang, when compared to other areas. Furthermore, sixteen different PAH gene mutation types were identified for the first time in the minorities in Xinjiang. Distinctive mutation spectrum of PAH gene in PKU patients from Xinjiang were characterized, which may promote the construction of PAH gene mutation database and serve as valuable tools for genetic diagnosis and counseling, and prognostic evaluation for PKU cases in the local area. PMID:25550961

Yu, Wuzhong; He, Jiang; Yang, Xi; Zou, Hongyun; Gui, Junhao; Wang, Rui; Yang, Liu; Wang, Zheng; Lei, Quan

2014-01-01

220

Revisiting MSUD in Portuguese Gypsies: evidence for a founder mutation and for a mutational hotspot within the BCKDHA gene.  

PubMed

Maple syrup urine disease (MSUD) is a rare autosomal recessive disorder of branched-chain amino acid metabolism. In the context of the wide mutational spectrum known for this disease, a few common mutations have been described in populations where founder effects played a major role in modeling diversities. In Portugal, for instance, a high proportion of patients are of Gypsy origin and all share the same mutation (c.117delC-alpha; p.R40GfsX23), causing the neonatal severe form of MSUD. In this study, we used four microsatellite markers closely flanking the BCKDHA gene (E1alpha protein) to demonstrate that c.117delC-alpha is a founder mutation responsible for the high incidence of the disorder among Portuguese Gypsies. These results are of medical relevance since carrier tests and prenatal diagnosis can be offered to families at risk, particularly because the carrier frequency of c.117delC-alpha was estimated at 1.4% among the healthy Portuguese Gypsies from the South of the country. Finally we present evidence that the genomic region of the BCKDHA gene where c.117delC-alpha is located is likely a mutational hotspot, since recurrence of c.117delC-alpha was observed in two distinct population groups. PMID:19456321

Quental, Sofia; Gusmăo, Alfredo; Rodríguez-Pombo, Pilar; Ugarte, Magdalena; Vilarinho, Laura; Amorim, António; Prata, Maria J

2009-05-01

221

APP717, APP693, and PRIP gene mutations are rare in Alzheimer disease  

PubMed Central

The amyloid precursor protein (APP) gene codes for the precursor to the ?-protein found in the amyloid deposits of Alzheimer disease (AD). Recently Goate et al. identified in codon 717 of this gene a missense mutation which segregates with AD in a familial AD (FAD) kindred. The same mutation was also found in affected subjects from a second FAD family but not in other FAD families or in normal controls. The following work was undertaken to determine the frequency of the codon 717 mutation in FAD and nonfamilial AD cases and in normal controls. We tested 76 FAD families, 127 “sporadic” AD subjects, 16 Down syndrome cases, and 256 normal controls for this mutation, and none were positive. We also tested for the APP codon 693 mutation associated with hereditary cerebral hemorrhage with amyloidosis–Dutch type, for PRIP gene missense mutations at codons 102, 117, and 200, and for the PRIP insertion mutations which are associated with Creutzfeld-Jakob disease and Gerstmann-Straussler Scheinker syndrome. No examples of these mutations were found in our population. Thus these APP and PRIP mutations are rare in both FAD and nonfamilial AD. ImagesFigure 1 PMID:1679288

Schellenberg, Gerard D.; Anderson, Leojean; O'dahl, Sheldon; Wisjman, Ellen M.; Sadovnick, Adele D.; Ball, Melvyn J.; Larson, Eric B.; Kukull, Walter A.; Martin, George M.; Roses, Allen D.; Bird, Thomas D.

1991-01-01

222

Mutated human androgen receptor gene detected in a prostatic cancer patient is also activated by estradiol  

SciTech Connect

Androgens are necessary for the development of prostatic cancer. The mechanisms by which the originally androgen-dependent prostatic cancer cells are relieved of the requirement to use androgen for their growth are largely unknown. The human prostatic cancer cell line LNCaP has been shown to contain a point mutation in the human androgen receptor gene (hAR), suggesting that changes in the hAR may contribute to the abnormal hormone response of prostatic cells. To search for point mutations in the hAR, we used single strand conformation polymorphism analysis and a polymerase chain reaction direct sequencing method to screen 23 prostatic cancer specimens from untreated patients, 6 prostatic cancer specimens from treated patients, and 11 benign prostatic hyperplasia specimens. One mutation was identified in DNA isolated from prostatic cancer tissue, and the mutation was also detected in the leukocyte DNA of the patient and his offspring. The mutation changed codon 726 in exon E from arginine to leucine and was a germ line mutation. The mutation we found in exon E of the hAR gene does not alter the ligand binding specificity of the AR, but the mutated receptor was activated by estradiol to a significantly greater extent than the wild-type receptor. The AR gene mutation described in this study might be one explanation for the altered biological activity of prostatic cancer. 36 refs., 4 figs.

Elo, J.P.; Kvist, L.; Leinonen, K.; Isomaa, V. [Univ. of Oulu (Finland)] [and others] [Univ. of Oulu (Finland); and others

1995-12-01

223

Relation of Gene Expression Phenotype to Immunoglobulin Mutation Genotype in B Cell Chronic Lymphocytic Leukemia  

Microsoft Academic Search

The most common human leukemia is B cell chronic lymphocytic leukemia (CLL), a malig- nancy of mature B cells with a characteristic clinical presentation but a variable clinical course. The rearranged immunoglobulin (Ig) genes of CLL cells may be either germ-line in sequence or somatically mutated. Lack of Ig mutations defined a distinctly worse prognostic group of CLL patients raising

Andreas Rosenwald; Ash A. Alizadeh; George Widhopf; Richard Simon; R. Eric Davis; Xin Yu; Liming Yang; Oxana K. Pickeral; Laura Z. Rassenti; John Powell; David Botstein; John C. Byrd; Michael R. Grever; Bruce D. Cheson; Nicholas Chiorazzi; Wyndham H. Wilson; Thomas J. Kipps; Patrick O. Brown; Louis M. Staudt

2001-01-01

224

Mutation in the 3' region of the alpha-1-antitrypsin gene and chronic obstructive pulmonary disease  

Microsoft Academic Search

A mutation in the 3' flanking region of the alpha-1-antitrypsin gene has been reported to be associated with chronic obstructive pulmonary disease (COPD). We have investigated the prevalence of this mutation in a group of 185 patients with airway obstruction and in 69 non-obstructed controls. The subjects were selected on the basis of their development of lung cancer and therefore

A J Sandford; J J Spinelli; T D Weir; P D Paré

1997-01-01

225

A NATURALLY OCCURRING EPIGENETIC MUTATION IN AN SBP-BOX GENE INHIBITS TOMATO FRUIT RIPENING  

Technology Transfer Automated Retrieval System (TEKTRAN)

A major player in the regulatory network controlling fruit ripening is likely to be the gene at the tomato Colorless non-ripening (Cnr) locus 1,2. The Cnr mutation results in colorless fruits with a significant loss of cell to cell adhesion. The nature of the mutation and the identity of the Cnr g...

226

Mutational hot spot in the p53 gene in human hepatocellular carcinomas  

Microsoft Academic Search

HUMAN hepatocellular carcinomas (HCC) from patients in Qidong, an area of high incidence in China, in which both hepatitis B virus and aflatoxin B1 are risk factors1, were analysed for mutations in p53, a putative tumour-suppressor gene. Eight of the 16 HCC had a point mutation at the third base position of codon 249. The G --> T transversion in

I. C. Hsu; R. A. Metcalf; T. Sun; J. A. Welsh; N. J. Wang; C. C. Harris

1991-01-01

227

A mutation in the HSD11B2 gene in a family with apparent mineralocorticoid excess  

SciTech Connect

A mutation in the HSD11B2 gene has been discovered in a consanguineous Iranian family with three sibs suffering from Apparent Mineralocorticoid Excess (AME). Sequence data demonstrate a C to T transition resulting in an R337C mutation. 9 refs., 2 figs., 3 tabs.

Wilson, R.C.; Harbison, M.D.; Wei, J.Q. [New York Hospital-Cornell Medical Center, NY (United States)] [and others] [New York Hospital-Cornell Medical Center, NY (United States); and others

1995-07-01

228

Mutation frequencies of Xlinked mental retardation genes in families from the EuroMRX consortium.  

E-print Network

Mutation frequencies of Xlinked mental retardation genes in families from the EuroMRX consortium Xlinked mental retardation (XLMR). After exclusion of Fragile X (Fra X) syndrome, probands from carriers, the mental retardation phenotype could be explained by a mutation. There was no difference

Institut des Sciences Cognitives, CNRS

229

Detection of point mutation in the p53 gene using a peptide nucleic acid biosensor  

Microsoft Academic Search

A 17-mer peptide nucleic acid (PNA) is used as the recognition layer of an electrochemical biosensor for detecting a specific mutation in the p53 gene. The performance of the PNA-derived biosensor is compared with that of its DNA counterpart. The significantly higher specificity of the PNA probe greatly improves the detection of a single point mutation, found in many types

Joseph Wang; Gustavo Rivas; Xiaohua Cai; Manuel Chicharro; Concepcion Parrado; Narasaiah Dontha; Asher Begleiter; Michael Mowat; Emil Palecek; Peter E. Nielsen

1997-01-01

230

Clinical and Biological Features Associated With Epidermal Growth Factor Receptor Gene Mutations in Lung Cancers  

Microsoft Academic Search

Background: Mutations in the tyrosine kinase (TK) domain of the epidermal growth factor receptor (EGFR) gene in lung cancers are associated with increased sensitivity of these can- cers to drugs that inhibit EGFR kinase activity. However, the role of such mutations in the pathogenesis of lung cancers is unclear. Methods: We sequenced exons 18 - 21 of the EGFR TK

Hisayuki Shigematsu; Li Lin; Takao Takahashi; Masaharu Nomura; Makoto Suzuki; Ignacio I. Wistuba; Kwun M. Fong; Huei Lee; Shinichi Toyooka; Nobuyoshi Shimizu; Takehiko Fujisawa; Ziding Feng; Jack A. Roth; Joachim Herz; John D. Minna; Adi F. Gazdar

231

Mutations in the human RAX homeobox gene in a patient with anophthalmia and sclerocornea  

Microsoft Academic Search

Anophthalmia and microphthalmia are among the most common ocular birth defects and a significant cause of congenital blindness. The etiology of anophthalmia and microphthalmia is diverse, with multiple genetic mutations associated with each of these conditions, along with potential environmental causes. Based on findings that mutations in the Rx\\/Rax homeobox genes in mice and fish lead to defects in retinal

Vera A. Voronina; Elena A. Kozhemyakina; Christina M. O'Kernick; Natan D. Kahn; Sharon L. Wenger; John V. Linberg; Adele S. Schneider; Peter H. Mathers

2004-01-01

232

Novel mutations in K13 propeller gene of artemisinin-resistant Plasmodium falciparum.  

PubMed

We looked for mutations in the Plasmodium falciparum K13 propeller gene of an artemisinin-resistant parasite on islands in Lake Victoria, Kenya, where transmission in 2012-2013 was high. The 4 new types of nonsynonymous, and 5 of synonymous, mutations we detected among 539 samples analyzed provide clues to understanding artemisinin-resistant parasites. PMID:25695257

Isozumi, Rie; Uemura, Haruki; Kimata, Isao; Ichinose, Yoshio; Logedi, John; Omar, Ahmeddin H; Kaneko, Akira

2015-03-01

233

Mutations and a polymorphism in the factor VIII gene discovered by denaturing gradient gel electrophoresis  

SciTech Connect

Hemophilia A results from mutations in the gene coding for coagulation factor VIII. The authors gradient gel electrophoresis to screen for mutations in the region of the factor VIII gene coding for the first acidic domain. Amplification primers were designed employing the MELTMAP computer program to optimize the ability to detect mutations. Screening of amplified DNA from 228 unselected hemophilia A patients revealed two mutations and one polymorphism. Rescreening the same population by making heteroduplexes between amplified patient and control samples prior to electrophoresis revealed one additional mutation. The mutations include two missense and one 4-base-pair deletion, and each mutation was found in patients with severe hemophilia. The polymorphism, located adjacent to the adenine branch site in intron 7, is useful for genetic prediction in some cases where the Bcl I and Xba I polymorphisms are uninformative. These results suggest that DNA amplification and denaturing gradient gel electrophoresis should be an excellent strategy for identifying mutations and polymorphisms in defined regions of the factor VIII gene and other large genes.

Kogan, S.; Gitschier, J. (Univ. of California, San Francisco (USA))

1990-03-01

234

A compound heterozygous mutation in the BSND gene detected in Bartter syndrome type IV  

Microsoft Academic Search

Bartter syndrome is a genetic disorder with hypokalemic metabolic alkalosis and is classified into five types. Type IV Bartter syndrome is a type of neonatal Bartter syndrome with sensorineural deafness and has been recently shown to be caused by mutations in the BSND gene. Owing to the rarity of this disease, only a limited number of mutations have been reported. We

Sachiko Kitanaka; Utako Sato; Kenichi Maruyama; Takashi Igarashi

2006-01-01

235

Mutations of the p53 gene in human myeloma cell lines.  

PubMed

Mutations affecting the p53 gene have been found associated with many human malignancies, but little is as yet known about multiple myeloma. We investigated p53 gene alterations in 10 human myeloma cell lines (HMCL), half of these being dependent upon exogenous interleukin 6 (IL-6) for in vitro growth, similar to freshly explanted myeloma cells. Using a polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) approach, eight of the 10 HMCL were found to bear a mutated p53 gene. All the mutations were single base substitutions with a predominance of G:C to A:T transitions. There was no apparent relation between the presence of a mutation and IL-6 requirement of the cell line. Interestingly, in two cell lines (XG-2 and XG-4) the SSCP pattern showed the presence of both the wild-type and the mutated allele and, upon reverse PCR on RNA, both alleles were found to be concomitantly expressed at the RNA level. Moreover, three freshly explanted tumor samples had the same p53 gene status (mutated versus wild type) as the HMCL that were derived from them. These results show that p53 mutations are frequent in HMCL. Although no apparent relation could be evidenced with the loss of exogenous IL-6 requirement, it may prove interesting to investigate further potential relations between the presence of a mutated p53 allele and gradual autonomy for cell growth. PMID:1373872

Mazars, G R; Portier, M; Zhang, X G; Jourdan, M; Bataille, R; Theillet, C; Klein, B

1992-05-01

236

Different ras gene mutational frequencies in thyroid papillary carcinomas in Japan and Thailand  

Microsoft Academic Search

The incidence and pattern of ras oncogene mutations in human malignancies demonstrate geographic and racial differences. For example, specificity of alterations is found in cholangiocellular carcinomas in Thai patients with a different etiology from those in Japanese patients. In the present study, a comparison of ras gene mutations in thyroid papillary carcinomas from Japanese and Thai patients was performed using

Hiroaki Naito; Chawalit Pairojkul; Yoshiteru Kitahori; Katsunari Yane; Hiroshi Miyahara; Noboru Konishi; Takashi Matsunaga; Yoshio Hiasa

1998-01-01

237

Mutational analysis of EGFR and K-RAS genes in lung adenocarcinomas  

Microsoft Academic Search

Both epidermal growth factor receptor (EGFR) and RAS gene mutations contribute to the development of non-small cell lung cancer (NSCLC). Because RAS is one of the downstream molecules in the EGFR signal transduction, the association between the somatic mutations of EGFR and RAS may be important in the pathogenesis of NSCLC . However, to date, such data are lacking. In

Young Hwa Soung; Jong Woo Lee; Su Young Kim; Si Hyung Seo; Won Sang Park; Suk Woo Nam; Sang Yong Song; Joung Ho Han; Cheol Keun Park; Jung Young Lee; Nam Jin Yoo; Sug Hyung Lee

2005-01-01

238

Novel Mutations in K13 Propeller Gene of Artemisinin-Resistant Plasmodium falciparum  

PubMed Central

We looked for mutations in the Plasmodium falciparum K13 propeller gene of an artemisinin-resistant parasite on islands in Lake Victoria, Kenya, where transmission in 2012–2013 was high. The 4 new types of nonsynonymous, and 5 of synonymous, mutations we detected among 539 samples analyzed provide clues to understanding artemisinin-resistant parasites. PMID:25695257

Uemura, Haruki; Kimata, Isao; Ichinose, Yoshio; Logedi, John; Omar, Ahmeddin H.; Kaneko, Akira

2015-01-01

239

Correlation of sweat chloride concentration with classes of the cystic fibrosis transmembrane conductance regulator gene mutations  

Microsoft Academic Search

Objective: To compare differences in epithelial chloride conductance according to class of mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Methods: We evaluated the relationship between the functional classes of CFTR mutations and chloride conductance using the first diagnostic sweat chloride concentration in a large cystic fibrosis (CF) population. Results: There was no difference in sweat chloride value

Michael Wilschanski; Julian Zielenski; Danuta Markiewicz; Lap-Chee Tsui; Mary Corey; Henry Levison; Peter R. Durie

1995-01-01

240

High Accuracy Mutation Detection in Leukemia on a Selected Panel of Cancer Genes  

PubMed Central

With the advent of whole-genome and whole-exome sequencing, high-quality catalogs of recurrently mutated cancer genes are becoming available for many cancer types. Increasing access to sequencing technology, including bench-top sequencers, provide the opportunity to re-sequence a limited set of cancer genes across a patient cohort with limited processing time. Here, we re-sequenced a set of cancer genes in T-cell acute lymphoblastic leukemia (T-ALL) using Nimblegen sequence capture coupled with Roche/454 technology. First, we investigated how a maximal sensitivity and specificity of mutation detection can be achieved through a benchmark study. We tested nine combinations of different mapping and variant-calling methods, varied the variant calling parameters, and compared the predicted mutations with a large independent validation set obtained by capillary re-sequencing. We found that the combination of two mapping algorithms, namely BWA-SW and SSAHA2, coupled with the variant calling algorithm Atlas-SNP2 yields the highest sensitivity (95%) and the highest specificity (93%). Next, we applied this analysis pipeline to identify mutations in a set of 58 cancer genes, in a panel of 18 T-ALL cell lines and 15 T-ALL patient samples. We confirmed mutations in known T-ALL drivers, including PHF6, NF1, FBXW7, NOTCH1, KRAS, NRAS, PIK3CA, and PTEN. Interestingly, we also found mutations in several cancer genes that had not been linked to T-ALL before, including JAK3. Finally, we re-sequenced a small set of 39 candidate genes and identified recurrent mutations in TET1, SPRY3 and SPRY4. In conclusion, we established an optimized analysis pipeline for Roche/454 data that can be applied to accurately detect gene mutations in cancer, which led to the identification of several new candidate T-ALL driver mutations. PMID:22675565

Gianfelici, Valentina; Geerdens, Ellen; Vandepoel, Roel; Pauwels, Daphnie; Porcu, Michaël; Lahortiga, Idoya; Brys, Vanessa; Dirks, Willy G.; Quentmeier, Hilmar; Cloos, Jacqueline; Cuppens, Harry; Uyttebroeck, Anne; Vandenberghe, Peter; Cools, Jan; Aerts, Stein

2012-01-01

241

UCSD scientists find gene mutation for aggressive form of pancreatic cancer  

Cancer.gov

Researchers at the University of California, San Diego School of Medicine have identified a mutated gene common to adenosquamous carcinoma tumors – the first known unique molecular signature for this rare, but particularly virulent, form of pancreatic cancer.

242

21 CFR 866.5900 - Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.  

Code of Federal Regulations, 2014 CFR

...mutations and variants in the CFTR gene. It is intended as an aid in confirmatory diagnostic testing of individuals with suspected cystic fibrosis (CF), carrier identification, and newborn screening. This device is not intended for...

2014-04-01

243

21 CFR 866.5900 - Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.  

Code of Federal Regulations, 2010 CFR

...mutations and variants in the CFTR gene. It is intended as an aid in confirmatory diagnostic testing of individuals with suspected cystic fibrosis (CF), carrier identification, and newborn screening. This device is not intended for...

2010-04-01

244

21 CFR 866.5900 - Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.  

Code of Federal Regulations, 2012 CFR

...mutations and variants in the CFTR gene. It is intended as an aid in confirmatory diagnostic testing of individuals with suspected cystic fibrosis (CF), carrier identification, and newborn screening. This device is not intended for...

2012-04-01

245

21 CFR 866.5900 - Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.  

Code of Federal Regulations, 2013 CFR

...mutations and variants in the CFTR gene. It is intended as an aid in confirmatory diagnostic testing of individuals with suspected cystic fibrosis (CF), carrier identification, and newborn screening. This device is not intended for...

2013-04-01

246

21 CFR 866.5900 - Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.  

Code of Federal Regulations, 2011 CFR

...mutations and variants in the CFTR gene. It is intended as an aid in confirmatory diagnostic testing of individuals with suspected cystic fibrosis (CF), carrier identification, and newborn screening. This device is not intended for...

2011-04-01

247

Novel SOST gene mutation in a sclerosteosis patient from Morocco: a case report.  

PubMed

Sclerosteosis (OMIM 269500) is a rare autosomal recessive condition characterized by increased bone density associated with syndactyly. It is linked to a genetic defect in the SOST gene coding for sclerostin. So far, seven different loss-of-function mutations in SOST have been reported in patients with sclerosteosis. Recently, two mutations in LRP4 gene underlying sclerosteosis were identified, reflecting the genetic heterogeneity of this disease. We report here a 30-years-old Moroccan man presented with typical clinical and radiological features of sclerosteosis who carries a novel homozygous mutation in the SOST gene, characterized as a nonsense mutation (c.79C > T; p.Gln27?) in exon 1 of the SOST gene. This is to our knowledge the first case of sclerosteosis reported from Morocco and North Africa. PMID:24594238

Belkhribchia, Mohamed Reda; Collet, Corinne; Laplanche, Jean-Louis; Hassani, Redouane

2014-03-01

248

Mutations of ZFPM2/FOG2 gene in sporadic cases of tetralogy of Fallot.  

PubMed

Two out of 47 patients with sporadic tetralogy of Fallot (TOF), the most common cyanotic conotruncal heart defect (CTD), showed heterozygous missense mutations of the ZFPM2/FOG2 gene. Knockout mice carrying mutations in the ZFPM2/FOG2 gene have similarly been found to exhibit TOF. While both mutant ZFPM2/FOG2 proteins, E30G (c.88A>G) and S657G (c.1968A>G), retain the ability to bind the partner protein GATA4 and repress GATA4 mediated gene activation, the S657G, but not the E30G, mutation is subtly impaired in this function. ZFPM2/FOG2 gene mutations may contribute to some sporadic cases of TOF. PMID:14517948

Pizzuti, Antonio; Sarkozy, Anna; Newton, Anthea L; Conti, Emanuela; Flex, Elisabetta; Digilio, Maria Cristina; Amati, Francesca; Gianni, Debora; Tandoi, Caterina; Marino, Bruno; Crossley, Merlin; Dallapiccola, Bruno

2003-11-01

249

The Mutator Gene Swi8 Effects Specific Mutations in the Mating-Type Region of Schizosaccharomyces Pombe  

PubMed Central

The swi8(+) gene of Schizosaccharomyces pombe appears to be involved in the termination step of copy synthesis during mating-type (MT) switching. Mutations in swi8 confer a general mutator phenotype and, in particular, generate specific mutations in the MT region. Sequencing of the MT cassettes of the h(90) swi8-137 mutant revealed three altered sites. One is situated at the switching (smt) signal adjacent to the H1 homology box of the expression locus mat1:1. It reduces the rate of MT switching. The alteration at the smt signal arose frequently in other h(90) swi8 strains and is probably caused by gene conversion in which the sequence adjacent to the H1 box of mat2:2 is used as template. This change might be generated during the process of MT switching when hybrid DNA formation is anomalously extended into the more heterologous region flanking the H1 homology box. In addition to the gene conversion at mat1:1, two mutations were found in the H3 homology boxes of the silent cassettes mat2:2 and mat3:3. PMID:7851760

Fleck, O.; Rudolph, C.; Albrecht, A.; Lorentz, A.; Schar, P.; Schmidt, H.

1994-01-01

250

1/9/09 2:14 PMResearchers Pinpoint Spontaneous Gene Mutations Responsible for 10 Percent of Non-Familial Cases of Schizophrenia Page 1 of 3http://cumc.columbia.edu/news/press_releases/gene-mutation-schizophrenia.html  

E-print Network

-Familial Cases of Schizophrenia Page 1 of 3http://cumc.columbia.edu/news/press_releases/gene-mutation-schizophrenia Gene Mutations Responsible for 10 Percent of Non-Familial Cases of Schizophrenia NEW YORK (May 30, 2008) ­ Scans of the genome of patients with schizophrenia have revealed rare spontaneous copy number mutations

251

Phenotypic heterogeneity in British patients with a founder mutation in the FHL1 gene.  

PubMed

Mutations in the four-and-a-half LIM domain 1 (FHL1) gene, which encodes a 280-amino-acid protein containing four LIM domains and a single zinc-finger domain in the N-terminal region, have been associated with a broad clinical spectrum of X-linked muscle diseases encompassing a variety of different phenotypes. Patients might present with a scapuloperoneal myopathy, a myopathy with postural muscle atrophy and generalized hypertrophy, an Emery-Dreifuss muscular dystrophy, or an early onset myopathy with reducing bodies. It has been proposed that the phenotypic variability is related to the position of the mutation within the FHL1 gene. Here, we report on three British families with a heterogeneous clinical presentation segregating a single FHL1 gene mutation and haplotype, suggesting that this represents a founder mutation. The underlying FHL1 gene mutation was detected by direct sequencing and the founder effect was verified by haplotype analysis of the FHL1 gene locus. A 3-bp insertion mutation (p.Phe127_Thr128insIle) within the second LIM domain of the FHL1 gene was identified in all available affected family members of the three families. Haplotype analysis of the FHL1 region on Xq26 revealed that the families shared a common haplotype. The p.Phe127_Thr128insIle mutation in the FHL1 gene therefore appears to be a British founder mutation and FHL1 gene screening, in particular of exon 6, should therefore be indicated in British patients with a broad phenotypic spectrum of X-linked muscle diseases. PMID:21629301

Sarkozy, Anna; Windpassinger, Christian; Hudson, Judith; Dougan, Charlotte F; Lecky, Bryan; Hilton-Jones, David; Eagle, Michelle; Charlton, Richard; Barresi, Rita; Lochmüller, Hanns; Bushby, Kate; Straub, Volker

2011-10-01

252

Phenotypic heterogeneity in British patients with a founder mutation in the FHL1 gene  

PubMed Central

Mutations in the four-and-a-half LIM domain 1 (FHL1) gene, which encodes a 280-amino-acid protein containing four LIM domains and a single zinc-finger domain in the N-terminal region, have been associated with a broad clinical spectrum of X-linked muscle diseases encompassing a variety of different phenotypes. Patients might present with a scapuloperoneal myopathy, a myopathy with postural muscle atrophy and generalized hypertrophy, an Emery–Dreifuss muscular dystrophy, or an early onset myopathy with reducing bodies. It has been proposed that the phenotypic variability is related to the position of the mutation within the FHL1 gene. Here, we report on three British families with a heterogeneous clinical presentation segregating a single FHL1 gene mutation and haplotype, suggesting that this represents a founder mutation. The underlying FHL1 gene mutation was detected by direct sequencing and the founder effect was verified by haplotype analysis of the FHL1 gene locus. A 3-bp insertion mutation (p.Phe127_Thr128insIle) within the second LIM domain of the FHL1 gene was identified in all available affected family members of the three families. Haplotype analysis of the FHL1 region on Xq26 revealed that the families shared a common haplotype. The p.Phe127_Thr128insIle mutation in the FHL1 gene therefore appears to be a British founder mutation and FHL1 gene screening, in particular of exon 6, should therefore be indicated in British patients with a broad phenotypic spectrum of X-linked muscle diseases. PMID:21629301

Sarkozy, Anna; Windpassinger, Christian; Hudson, Judith; Dougan, Charlotte F; Lecky, Bryan; Hilton-Jones, David; Eagle, Michelle; Charlton, Richard; Barresi, Rita; Lochmüller, Hanns; Bushby, Kate; Straub, Volker

2011-01-01

253

A novel mutation in the calcium channel gene in a family with hypokalemic periodic paralysis  

Microsoft Academic Search

Hypokalemic periodic paralysis (HypoPP) type 1 is an autosomal dominant disease caused by mutations in the Ca(V)1.1 calcium channel encoded by the CACNA1S gene. Only seven mutations have been found since the discovery of the causative gene in 1994. We describe a patient with HypoPP who had a high serum potassium concentration after recovery from a recent paralysis, which complicated

Makito Hirano; Yosuke Kokunai; Asami Nagai; Yusaku Nakamura; Kazumasa Saigoh; Susumu Kusunoki; Masanori P. Takahashi

2011-01-01

254

Seven novel mutations of the PKD2 gene in families with autosomal dominant polycystic kidney disease  

Microsoft Academic Search

Seven novel mutations of thePKD2gene in families with autosomal dominant polycystic kidney disease.BackgroundAutosomal dominant polycystic kidney disease (ADPKD) is genetically heterogeneous, with at least three chromosomal loci accounting for the disease. Mutations in the PKD2 gene on the long arm of chromosome 4 are expected to be responsible for approximately 15% of cases of ADPKD.MethodsWe report a systematic screening for

Roser Torra; Miguel Viribay; Dolores Tellería; Cčlia Badenas; Michael Watson; Peter Harris; Alejandro Darnell; José L San Millán

1999-01-01

255

Left Ventricular Noncompaction in a Family with Lamin A/C Gene Mutation  

PubMed Central

Left ventricular noncompaction is a rare type of cardiomyopathy, the genetics of which are poorly understood to date. Lamin A/C gene mutations have been associated with dilated cardiomyopathy and diseases of the conduction system, but rarely in left ventricular noncompaction cardiomyopathy. This report describes the cases of 4 family members with a lamin A/C gene mutation, 3 of whom had phenotypic expression of left ventricular noncompaction.

Towbin, Jeffrey A.; Jefferies, John L.

2015-01-01

256

Novel Mutations in Thiazide-Sensitive NaCl Cotransporter Gene of Patients with Gitelman's Syndrome  

Microsoft Academic Search

Gitelman's syndrome (GS) is an autosomal recessive disorder characterized by metabolic alkalosis, hypokalemia, hypomagnesemia, and hypocalciuria that has recently been reported to be linked to thiazide-sensitive Na-Cl cotransporter (TSC) gene mutations. In this study, possible mutations in the TSC gene of six Japanese patients clinically diagnosed with GS were investigated. Twenty-six exons encoding TSC were am- plified by PCR and

TOSHIAKI MONKAWA; ISAO KURIHARA; KAZUO KOBAYASHI; MATSUHIKO HAYASHI; TAKAO SARUTA

257

Muscular dystrophy with marked Dysferlin deficiency is consistently caused by primary dysferlin gene mutations  

Microsoft Academic Search

Dysferlin is a 237-kDa transmembrane protein involved in calcium-mediated sarcolemma resealing. Dysferlin gene mutations cause limb-girdle muscular dystrophy (LGMD) 2B, Miyoshi myopathy (MM) and distal myopathy of the anterior tibialis. Considering that a secondary Dysferlin reduction has also been described in other myopathies, our original goal was to identify cases with a Dysferlin deficiency without dysferlin gene mutations. The dysferlin

Mafalda Cacciottolo; Gelsomina Numitone; Stefania Aurino; Imma Rosaria Caserta; Marina Fanin; Luisa Politano; Carlo Minetti; Enzo Ricci; Giulio Piluso; Corrado Angelini; Vincenzo Nigro

2011-01-01

258

Whole exome sequencing reveals concomitant mutations of multiple FA genes in individual Fanconi anemia patients  

PubMed Central

Background Fanconi anemia (FA) is a rare inherited genetic syndrome with highly variable clinical manifestations. Fifteen genetic subtypes of FA have been identified. Traditional complementation tests for grouping studies have been used generally in FA patients and in stepwise methods to identify the FA type, which can result in incomplete genetic information from FA patients. Methods We diagnosed five pediatric patients with FA based on clinical manifestations, and we performed exome sequencing of peripheral blood specimens from these patients and their family members. The related sequencing data were then analyzed by bioinformatics, and the FANC gene mutations identified by exome sequencing were confirmed by PCR re-sequencing. Results Homozygous and compound heterozygous mutations of FANC genes were identified in all of the patients. The FA subtypes of the patients included FANCA, FANCM and FANCD2. Interestingly, four FA patients harbored multiple mutations in at least two FA genes, and some of these mutations have not been previously reported. These patients’ clinical manifestations were vastly different from each other, as were their treatment responses to androstanazol and prednisone. This finding suggests that heterozygous mutation(s) in FA genes could also have diverse biological and/or pathophysiological effects on FA patients or FA gene carriers. Interestingly, we were not able to identify de novo mutations in the genes implicated in DNA repair pathways when the sequencing data of patients were compared with those of their parents. Conclusions Our results indicate that Chinese FA patients and carriers might have higher and more complex mutation rates in FANC genes than have been conventionally recognized. Testing of the fifteen FANC genes in FA patients and their family members should be a regular clinical practice to determine the optimal care for the individual patient, to counsel the family and to obtain a better understanding of FA pathophysiology. PMID:24885126

2014-01-01

259

A Novel Activating Mutation of the K- ras Gene in Human Primary Colon Adenocarcinoma  

Microsoft Academic Search

We identified a novel type of point mutation at the 22nd codon of the K-ras gene in a primary colon cancer. The mutation was C to A transversion substituting lysine (AAG) for normal glutamine (CAG) codon. Biological activity of this mutant K-ras gene was tested by expression of full-length cDNA clones in NIH3T3 cells. Most of the K-ras Lys22-transfected cells

Kazunori Tsukuda; Motohiko Tanino; Hiroyuki Soga; Nobuyoshi Shimizu; Kenji Shimizu

2000-01-01

260

Pseudohypoaldosteronism Type 1 due to a Novel Mutation in the Mineralocorticoid Receptor Gene  

Microsoft Academic Search

Background\\/Aims: Autosomal dominant pseudohypoaldosteronism type 1 is caused by mutations in the mineralocorticoid receptor (NR3C2) gene, often leading to life-threatening hyponatremia and hyperkalemia in the newborn period. We report a novel mutation in the NR3C2 gene, and report, for the first time, the association of well-treated pseudohypoaldosteronism with failure to thrive. This report additionally highlights the importance of aldosterone-sensitive sodium

Lindsey A. Loomba-Albrecht; Mato Nagel; Andrew A. Bremer

2010-01-01

261

Cystic fibrosis with three mutations in the cystic fibrosis transmembrane conductance regulator gene  

Microsoft Academic Search

Three mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene were discovered in a pancreas-insufficient patient with cystic fibrosis (CF) who displayed an uncommon combination of almost normal chloride concentration in sweat tests and typical symptoms of gastrointestinal and pulmonary disease. The R553Q mutation was found on the maternal ?F508-CFTR gene. Codon 553 is located within a consensus motif

Thilo Dörk; Ulrich Wulbrand; Thomas Richter; Thomas Neumann; Heiner Wolfes; Brigitte Wulf; Günter Maass; Burkhard Tümmler

1991-01-01

262

Novel Somatic Mutations to PI3K Pathway Genes in Metastatic Melanoma  

PubMed Central

Background BRAFV600 inhibitors have offered a new gateway for better treatment of metastatic melanoma. However, the overall efficacy of BRAFV600 inhibitors has been lower than expected in clinical trials, and many patients have shown resistance to the drug’s effect. We hypothesized that somatic mutations in the Phosphoinositide 3-Kinase (PI3K) pathway, which promotes proliferation and survival, may coincide with BRAFV600 mutations and contribute to chemotherapeutic resistance. Methods We performed a somatic mutation profiling study using the 454 FLX pyrosequencing platform in order to identify candidate cancer genes within the MAPK and PI3K pathways of melanoma patients. Somatic mutations of theses candidate cancer genes were then confirmed using Sanger sequencing. Results As expected, BRAFV600 mutations were seen in 51% of the melanomas, whereas NRAS mutations were seen in 19% of the melanomas. However, PI3K pathway mutations, though more heterogeneous, were present in 41% of the melanoma, with PTEN being the highest mutated PI3K gene in melanomas (22%). Interestingly, several novel PI3K pathway mutations were discovered in MTOR, IRS4, PIK3R1, PIK3R4, PIK3R5, and NFKB1. PI3K pathway mutations co-occurred with BRAFV600 mutations in 17% of the tumors and co-occurred with 9% of NRAS mutant tumors, implying cooperativity between these pathways in terms of melanoma progression. Conclusions These novel PI3K pathway somatic mutations could provide alternative survival and proliferative pathways for metastatic melanoma cells. They therefore may be potential chemotherapeutic targets for melanoma patients who exhibit resistance to BRAFV600 inhibitors. PMID:22912864

Ramasamy, Poornema; Leskoske, Kristin; Oroian, Dora; Birtwistle, Marc R.; Buckhaults, Phillip J.

2012-01-01

263

Dystrophin Gene Mutation Location and the Risk of Cognitive Impairment in Duchenne Muscular Dystrophy  

PubMed Central

Background A significant component of the variation in cognitive disability that is observed in Duchenne muscular dystrophy (DMD) is known to be under genetic regulation. In this study we report correlations between standardised measures of intelligence and mutational class, mutation size, mutation location and the involvement of dystrophin isoforms. Methods and Results Sixty two male subjects were recruited as part of a study of the cognitive spectrum in boys with DMD conducted at the Sydney Children's Hospital (SCH). All 62 children received neuropsychological testing from a single clinical psychologist and had a defined dystrophin gene (DMD) mutation; including DMD gene deletions, duplications and DNA point mutations. Full Scale Intelligence Quotients (FSIQ) in unrelated subjects with the same mutation were found to be highly correlated (r?=?0.83, p?=?0.0008), in contrast to results in previous publications. In 58 cases (94%) it was possible to definitively assign a mutation as affecting one or more dystrophin isoforms. A strong association between the risk of cognitive disability and the involvement of groups of DMD isoforms was found. In particular, improvements in the correlation of FSIQ with mutation location were identified when a new classification system for mutations affecting the Dp140 isoform was implemented. Significance These data represent one of the largest studies of FSIQ and mutational data in DMD patients and is among the first to report on a DMD cohort which has had both comprehensive mutational analysis and FSIQ testing through a single referral centre. The correlation between FSIQ results with the location of the dystrophin gene mutation suggests that the risk of cognitive deficit is a result of the cumulative loss of central nervous system (CNS) expressed dystrophin isoforms, and that correct classification of isoform involvement results in improved estimates of risk. PMID:20098710

Maroulis, Sarah; Gilissen, Christian; Pedersen, Robyn L.; Mowat, David R.; Johnston, Heather M.; Buckley, Michael F.

2010-01-01

264

Screening for germline mutations in the neurofibromatosis type 2 (NF2) gene in NF2 patients  

SciTech Connect

Neurofibromatosis type 2 (NF2) is an autosomal dominant disease with over 95% penetrance which predisposes gene carriers to develop multiple tumors of the central nervous system. The NF2 gene is a putative tumor suppressor gene which was previously mapped to the long arm of chromosome 22, and has recently been identified, using positional cloning techniques. The gene encodes a protein, schwannomin (SCH), which is highly homologous to the band 4.1 protein family. In an attempt to identify and characterize mutations which lead to the manifestation of the disease, we have used single strand conformation analysis (SSCA) to screen for germline mutations in all 17 exons of the NF2 gene in 59 unrelated NF2 patients, representing both familial and new mutations. A total of 27 migration abnormalities was found in 26 patients. Using direct sequencing analysis, the majority of these variants were found to result in nonsense, splice-site or frameshift mutations. Mutations identified in familial NF2 patients segregate in the family, and may prove to be useful tools for a simple and direct SSCA-based technique of presymptomatic or prenatal diagnosis in relatives of patients with NF2. This may be of particular importance in children of patients who have new mutations in the NF2 gene, where linkage analysis may not be feasible.

Andermann, A.A.; Ruttledge, M.H.; Rangaratnam, A. [McGill Univ. and Montreal General Hospital Research Institute, Quebec (Canada)] [and others

1994-09-01

265

Three novel PHEX gene mutations in four Chinese families with X-linked dominant hypophosphatemic rickets  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer In our study, all of the patients were of Han Chinese ethnicity, which were rarely reported. Black-Right-Pointing-Pointer We identified three novel PHEX gene mutations in four unrelated families with XLH. Black-Right-Pointing-Pointer We found that the relationship between the phenotype and genotype of the PHEX gene was not invariant. Black-Right-Pointing-Pointer We found that two PHEX gene sites, p.534 and p.731, were conserved. -- Abstract: Background: X-linked hypophosphatemia (XLH), the most common form of inherited rickets, is a dominant disorder that is characterized by renal phosphate wasting with hypophosphatemia, abnormal bone mineralization, short stature, and rachitic manifestations. The related gene with inactivating mutations associated with XLH has been identified as PHEX, which is a phosphate-regulating gene with homologies to endopeptidases on the X chromosome. In this study, a variety of PHEX mutations were identified in four Chinese families with XLH. Methods: We investigated four unrelated Chinese families who exhibited typical features of XLH by using PCR to analyze mutations that were then sequenced. The laboratory and radiological investigations were conducted simultaneously. Results: Three novel mutations were found in these four families: one frameshift mutation, c.2033dupT in exon 20, resulting in p.T679H; one nonsense mutation, c.1294A > T in exon 11, resulting in p.K432X; and one missense mutation, c.2192T > C in exon 22, resulting in p.F731S. Conclusions: We found that the PHEX gene mutations were responsible for XLH in these Chinese families. Our findings are useful for understanding the genetic basis of Chinese patients with XLH.

Kang, Qing-lin [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China)] [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); Xu, Jia [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China) [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); Medical College of Soochow University, Suzhou, Jiangsu province 215000 (China); Zhang, Zeng [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China) [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); He, Jin-wei [Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China)] [Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); Lu, Lian-song [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China) [Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); Medical College of Soochow University, Suzhou, Jiangsu province 215000 (China); Fu, Wen-zhen [Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China)] [Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China); Zhang, Zhen-lin, E-mail: zzl2002@medmail.com.cn [Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China)] [Metabolic Bone Disease and Genetic Research Unit, Department of Osteoporosis and Bone Diseases, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233 (China)

2012-07-13

266

Low Frequency of 185delAG Founder Mutation of BRCA1 Gene in Iranian Breast Cancer Patients  

Microsoft Academic Search

AIM: The mutations in two breast cancer susceptibility genes, BRCA1 and BRCA2, are frequently associated with familial breast cancer. In this study, we aimed to inves- tigate the probable founder mutations of BRCA1 and BRCA2 genes in Iranian breast cancer patients. METHODS: The total 400 patients affected with primary breast cancer were included in this study. Mutation detection was carried

Parvin Mehdipour; Saied Hosseini-Asl; Arezoo Savabi-E; Laleh Habibi; Ehsan Alvandi; Morteza Atri

267

Mutations of the PKD1 gene among Japanese autosomal dominant polycystic kidney disease patients, including one heterozygous mutation identified in members of the same family  

Microsoft Academic Search

More than 80 mutations of the PKD1 gene have been reported, mostly in patients from Western Europe. New techniques are being used to detect an increasing number\\u000a of mutations, even in the homologous region of the PKD1 gene. Polymerase chain reaction–single-strand conformation polymorphism (PCR-SSCP) or denaturing high-performance liquid\\u000a chromatography (DHPLC) analyses were performed in the present study to screen mutations

Michiko Mizoguchi; Takashi Tamura; Akiko Yamaki; Eiji Higashihara; Yoshiko Shimizu

2001-01-01

268

FGFR3 Mutations and the Skin: Report of a Patient with a FGFR3 Gene Mutation, Acanthosis Nigricans, Hypochondroplasia and Hyperinsulinemia and Review of the Literature  

Microsoft Academic Search

Fibroblast growth factor receptor 3 (FGFR3) gene mutations in the germline are well-known causes of skeletal syndromes. Somatic FGFR3 mutations have been found in malignant neoplasms and more recently in several cutaneous elements. We present a 14-year-old girl with mild hypochondroplasia who developed acanthosis nigricans. The report of a K650Q mutation in the FGFR3 gene in a similar case prompted

M. Blomberg; E. M. Jeppesen; F. Skovby; E. Benfeldt

2010-01-01

269

Mutation analysis of the parkin and PINK1 genes in American Caucasian early-onset Parkinson disease families  

Microsoft Academic Search

Mutations in the parkin gene and the PTEN-induced putative kinase 1 gene (PINK1) have been identified as the most common causes of autosomal recessive early-onset Parkinson disease (EOPD). To investigate the presence of the parkin and PINK1 gene mutation(s) and to explore genotype–phenotype correlations in American Caucasian families with EOPD from North American, we screened these two genes in probands

Hao Deng; Weidong Le; Joohi Shahed; Wenjie Xie; Joseph Jankovic

2008-01-01

270

Sodium channel gene mutations in hypokalemic periodic paralysis: an uncommon cause in the UK.  

PubMed

Eleven of 36 families with hypokalemic periodic paralysis (hypoPP) harbored mutations in the skeletal muscle calcium channel gene (CACNA1S). The authors screened the skeletal muscle sodium channel gene (SCN4A) in the remainder. One family harbored a new heterozygous point mutation C2014A in exon 12 (R672S) of SCN4A. The authors identified the genetic defect underlying hypoPP in 33% of individuals tested. The authors conclude that SCN4A mutations are an uncommon cause of hypoPP in this UK population. PMID:11591859

Davies, N P; Eunson, L H; Samuel, M; Hanna, M G

2001-10-01

271

Genomic organization of SLC3A1, a transporter gene mutated in cystinuria  

SciTech Connect

The SLC3A1 gene encodes a transport protein for cystine and the dibasic amino acids. Recently mutations in this gene have been shown to cause cystinuria. We report the genomic structure and organization of SLC3A1, which is composed of 10 exons and spans nearly 45 kb. Until now screening for mutations in SLC3A1 has been based on RT-PCR amplification of illegitimate mRNA transcripts from white blood cells. In this report we provide primers for amplification of exons from genomic DNA, thus simplifying the process of screening for SLC3A1 mutations in cystinuria. 20 refs., 3 figs., 2 tabs.

Pras, E.; Sood, R.; Raben, N. [National Inst. of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, MD (United States)] [National Inst. of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, MD (United States)

1996-08-15

272

LDL-R and Apo-B-100 gene mutations in Polish familial hypercholesterolemias.  

PubMed

A group of 30 Polish families with clinical signs of familial hypercholesterolemia was studied for the presence of germ-line mutations in the LDL-R and ApoB-100 genes. Screening of the LDL-R gene was performed at the genomic DNA level by single-strand conformation polymorphism analysis of all 18 exons and extended by sequencing of polymerase chain reaction (PCR) products showing abnormalities. The occurrence of large LDL-R gene alterations was evaluated by analysis of restriction enzyme patterns on Southern blots and using the long-PCR technique. The ApoB-100 gene was studied by combined allele-specific and asymmetric PCR for the occurrence of the common B-3500 missense mutation G to A at nucleotide position 10,708. Germ-line mutations were found in 17 families. In 12 of them LDL-R gene mutations were detected. Three of 11 different mutations had previously been described in other populations (3-bp deletion of codon 197; Ser156Leu; Gly571Glu). Of the mutations not previously recognized and identified in Polish families, there were three small deletions (2-bp deletion AG at codon 291; 4-bp deletion CCCT at codons 661-662; 1-bp deletion A at codon 830), and four point mutations (Arg239Stop, Cys331Stop, Asn543Ser, Gln665Stop). Additionally, one large (approximately 1-kb) LDL-R gene deletion between exons 6 and 9 was identified. In five families, the B-3500 mutation within the ApoB-100 gene was revealed. PMID:9654205

Górski, B; Kubalska, J; Naruszewicz, M; Lubi?ski, J

1998-05-01

273

[Some behavioral features in Drosophila melanogaster lines carrying a flamenco gene mutation].  

PubMed

Olfactory sensitivity and locomotor activity was assayed in Drosophila melanogaster strains carrying a mutation of the flamenco gene, which controls transposition of the mobile genetic element 4 (MGE4) retrotransposon the gypsy mobile element. A change in olfactory sensitivity was detected. The reaction to the odor of acetic acid was inverted in flies of the mutator strain (MS), which carried the flam mutation and active MGE4 copies and were characterized by genetic instability. Flies of the genetically unstable strains displayed a lower locomotor activity. The behavioral changes in MS flies can be explained by the pleiotropic effect of the flam mutation or by insertion mutations which arise in behavior genes as a result of genome destabilization by MGE4. PMID:11771305

Subocheva, E A; Romanova, L G; Romanova, N I; Kim, A I

2001-11-01

274

Inferring the Temporal Order of Cancer Gene Mutations in Individual Tumor Samples  

PubMed Central

The temporal order of cancer gene mutations in tumors is essential for understanding and treating the disease. Existing methods are unable to infer the order of mutations that are identified at the same time in individual tumor samples, leaving the heterogeneity of the order unknown. Here, we show that through a complex network-based approach, which is based on the newly defined statistic –carcinogenesis information conductivity (CIC), the temporal order in individual samples can be effectively inferred. The results suggest that tumor-suppressor genes might more frequently initiate the order of mutations than oncogenes, and every type of cancer might have its own unique order of mutations. The initial mutations appear to be dedicated to acquiring the function of evading apoptosis, and some order constraints might reflect potential regularities. Our approach is completely data-driven without any parameter settings and can be expected to become more effective as more data will become available. PMID:24586626

Guo, Jun; Guo, Hanliang; Wang, Zhanyi

2014-01-01

275

Characterization of six mutations in Exon 37 of neurofibromatosis type 1 gene  

SciTech Connect

Neurofibromatosis type 1 (NF1) is one of the most common inherited disorders, with an incidence of 1 in 3,000. We screened a total of 320 unrelated NF1 patients for mutations in exon 37 of the NF1 gene. Six independent mutations were identified, of which three are novel, and these include a recurrent nonsense mutation identified in 2 unrelated patients at codon 2281 (G2281X), a 1-bp insertion (6791 ins A) resulting in a change of TAG (tyrosine) to a TAA (stop codon), and a 3-bp deletion (6839 del TAC) which generated a frameshift. Another recurrent nonsense mutation, Y2264X, which was detected in 2 unrelated patients in this study, was also previously reported in 2 NF1 individuals. All the mutations were identified within a contiguous 49-bp sequence. Further studies are warranted to support the notion that this region of the gene contains highly mutable sequences. 17 refs., 2 figs., 1 tab.

Upadhyaya, M.; Osborn, M.; Maynard, J.; Harper, P. [Institute of Medical Genetics, Cardiff, Wales (United Kingdom)] [Institute of Medical Genetics, Cardiff, Wales (United Kingdom)

1996-07-26

276

De novo mutations in histone modifying genes in congenital heart disease  

PubMed Central

Congenital heart disease (CHD) is the most frequent birth defect, affecting 0.8% of live births1. Many cases occur sporadically and impair reproductive fitness, suggesting a role for de novo mutations. By analysis of exome sequencing of parent-offspring trios, we compared the incidence of de novo mutations in 362 severe CHD cases and 264 controls. CHD cases showed a significant excess of protein-altering de novo mutations in genes expressed in the developing heart, with an odds ratio of 7.5 for damaging mutations. Similar odds ratios were seen across major classes of severe CHD. We found a marked excess of de novo mutations in genes involved in production, removal or reading of H3K4 methylation (H3K4me), or ubiquitination of H2BK120, which is required for H3K4 methylation2–4. There were also two de novo mutations in SMAD2; SMAD2 signaling in the embryonic left-right organizer induces demethylation of H3K27me5. H3K4me and H3K27me mark `poised' promoters and enhancers that regulate expression of key developmental genes6. These findings implicate de novo point mutations in several hundred genes that collectively contribute to ~10% of severe CHD. PMID:23665959

Zaidi, Samir; Choi, Murim; Wakimoto, Hiroko; Ma, Lijiang; Jiang, Jianming; Overton, John D.; Romano-Adesman, Angela; Bjornson, Robert D.; Breitbart, Roger E.; Brown, Kerry K.; Carriero, Nicholas J.; Cheung, Yee Him; Deanfield, John; DePalma, Steve; Fakhro, Khalid A.; Glessner, Joseph; Hakonarson, Hakon; Italia, Michael; Kaltman, Jonathan R.; Kaski, Juan; Kim, Richard; Kline, Jennie K.; Lee, Teresa; Leipzig, Jeremy; Lopez, Alexander; Mane, Shrikant M.; Mitchell, Laura E.; Newburger, Jane W.; Parfenov, Michael; Pe'er, Itsik; Porter, George; Roberts, Amy; Sachidanandam, Ravi; Sanders, Stephan J.; Seiden, Howard S.; State, Mathew W.; Subramanian, Sailakshmi; Tikhonova, Irina R.; Wang, Wei; Warburton, Dorothy; White, Peter S.; Williams, Ismee A.; Zhao, Hongyu; Seidman, Jonathan G.; Brueckner, Martina; Chung, Wendy K.; Gelb, Bruce D.; Goldmuntz, Elizabeth; Seidman, Christine E.; Lifton, Richard P.

2013-01-01

277

Identification of candidate genes for lung cancer somatic mutation test kits  

PubMed Central

Over the past three decades, mortality from lung cancer has sharply and continuously increased in China, ascending to the first cause of death among all types of cancer. The ability to identify the actual sequence of gene mutations may help doctors determine which mutations lead to precancerous lesions and which produce invasive carcinomas, especially using next-generation sequencing (NGS) technology. In this study, we analyzed the latest lung cancer data in the COSMIC database, in order to find genomic “hotspots” that are frequently mutated in human lung cancer genomes. The results revealed that the most frequently mutated lung cancer genes are EGFR, KRAS and TP53. In recent years, EGFR and KRAS lung cancer test kits have been utilized for detecting lung cancer patients, but they presented many disadvantages, as they proved to be of low sensitivity, labor-intensive and time-consuming. In this study, we constructed a more complete catalogue of lung cancer mutation events including 145 mutated genes. With the genes of this list it may be feasible to develop a NGS kit for lung cancer mutation detection. PMID:24130455

Chen, Yong; Shi, Jian-Xin; Pan, Xu-Feng; Feng, Jian; Zhao, Heng

2013-01-01

278

A Novel Null Homozygous Mutation Confirms CACNA2D2 as a Gene Mutated in Epileptic Encephalopathy  

PubMed Central

Contribution to epileptic encephalopathy (EE) of mutations in CACNA2D2, encoding ?2?-2 subunit of Voltage Dependent Calcium Channels, is unclear. To date only one CACNA2D2 mutation altering channel functionality has been identified in a single family. In the same family, a rare CELSR3 polymorphism also segregated with disease. Involvement of CACNA2D2 in EE is therefore not confirmed, while that of CELSR3 is questionable. In a patient with epilepsy, dyskinesia, cerebellar atrophy, psychomotor delay and dysmorphic features, offspring to consanguineous parents, we performed whole exome sequencing (WES) for homozygosity mapping and mutation detection. WES identified extended autozygosity on chromosome 3, containing two novel homozygous candidate mutations: c.1295delA (p.Asn432fs) in CACNA2D2 and c.G6407A (p.Gly2136Asp) in CELSR3. Gene prioritization pointed to CACNA2D2 as the most prominent candidate gene. The WES finding in CACNA2D2 resulted to be statistically significant (p?=?0.032), unlike that in CELSR3. CACNA2D2 homozygous c.1295delA essentially abolished ?2?-2 expression. In summary, we identified a novel null CACNA2D2 mutation associated to a clinical phenotype strikingly similar to the Cacna2d2 null mouse model. Molecular and statistical analyses together argued in favor of a causal contribution of CACNA2D2 mutations to EE, while suggested that finding in CELSR3, although potentially damaging, is likely incidental. PMID:24358150

Pippucci, Tommaso; Parmeggiani, Antonia; Palombo, Flavia; Maresca, Alessandra; Angius, Andrea; Crisponi, Laura; Cucca, Francesco; Liguori, Rocco; Valentino, Maria Lucia; Seri, Marco; Carelli, Valerio

2013-01-01

279

A high frequency of distinct ATM gene mutations in ataxia-telangiectasia.  

PubMed Central

The clinical features of the autosomal recessive disorder ataxia-telangiectasia (AT) include a progressive cerebellar ataxia, hypersensitivity to ionizing radiation, and an increased susceptibility to malignancies. Epidemiological studies have suggested that AT heterozygotes may also be at increased risk for malignancy, possibly as a consequence of radiation exposure. A gene mutated in AT patients (ATM) has recently been isolated, making mutation screening in both patients and the general population possible. Because of the relatively large size of the ATM gene, the design of screening programs will depend on the types and distribution of mutations in the general population. In this report, we describe 30 mutations identified in a panel of unrelated AT patients and controls. Twenty-five of the 30 were distinct, and most patients were compound heterozygotes. The most frequently detected mutation was found in three different families and had previously been reported in five others. This corresponds to a frequency of 8% of all reported ATM mutations. Twenty-two of the alterations observed would be predicted to lead to protein truncation at sites scattered throughout the molecule. Two fibroblast cell lines, which displayed normal responses to ionizing radiation, also proved to be heterozygous for truncation mutations of ATM. These observations suggest that the carrier frequency of ATM mutations may be sufficiently high to make population screening practical. However, such screening may need to be done prospectively, that is, by searching for new mutations rather than by screening for just those already identified in AT families. PMID:8808599

Wright, J.; Teraoka, S.; Onengut, S.; Tolun, A.; Gatti, R. A.; Ochs, H. D.; Concannon, P.

1996-01-01

280

Mutations in the CLCN1 gene leading to myotonia congenita Thomsen and generalized myotonia Becker  

SciTech Connect

Autosomal dominant inherited myotonia congenita Thomsen (MC) and autosomal recessive generalized myotonia Becker (GM) are non-dystropic muscle disorders in which the symptom myotonia is based on an increased excitability of the muscle fiber membrane due to a reduced sarcolemmal chloride conductance. Affected individuals exhibit myotonic muscle stiffness in all skeletal muscles and a transient muscle weakness is particularly pronounced in the arms and hands of probands with the disorder GM. Recently we have shown linkage of the disorders MC and GM to the gene CLCN1 coding for the skeletal muscle chloride channel on chromosome 7 in German families. In addition we presented data supporting the hypothesis that GM is a genetically homogeneous disorder. Data are presented about an extended screen for mutations in the CLCN1 gene for our MC and GM population. We identified mainly missense mutations leading to altered amino acid codons. The previously described F413C mutation is by far the most common mutation for GM and is found in one family only (P480L, G482R, R496S). In addition we found 5{prime} donor and 3{prime} acceptor splice site mutations at various intron-exon boundaries, as well as a deletion mutation of 14 bp in exon 13. This deletion mutation is the second most common mutation in the GM population with a frequency of 8%. So far we have not determined sites of predominance of mutations in the CLCN1 gene, which could give us more insight into the regions critical for the function of the channel and the fact that the mutations in the gene may lead to dominant and recessive inheritance.

Koch, M.C.; Meyer-Kline, C.; Otto, M. [Universitaet Marburg, (Germany)] [and others

1994-09-01

281

Exome Analysis Reveals Differentially Mutated Gene Signatures of Stage, Grade and Subtype in Breast Cancers  

PubMed Central

Breast cancers exhibit highly heterogeneous molecular profiles. Although gene expression profiles have been used to predict the risks and prognostic outcomes of breast cancers, the high variability of gene expression limits its clinical application. In contrast, genetic mutation profiles would be more advantageous than gene expression profiles because genetic mutations can be stably detected and the mutational heterogeneity widely exists in breast cancer genomes. We analyzed 98 breast cancer whole exome samples that were sorted into three subtypes, two grades and two stages. The sum deleterious effect of all mutations in each gene was scored to identify differentially mutated genes (DMGs) for this case-control study. DMGs were corroborated using extensive published knowledge. Functional consequences of deleterious SNVs on protein structure and function were also investigated. Genes such as ERBB2, ESP8, PPP2R4, KIAA0922, SP4, CENPJ, PRCP and SELP that have been experimentally or clinically verified to be tightly associated with breast cancer prognosis are among the DMGs identified in this study. We also identified some genes such as ARL6IP5, RAET1E, and ANO7 that could be crucial for breast cancer development and prognosis. Further, SNVs such as rs1058808, rs2480452, rs61751507, rs79167802, rs11540666, and rs2229437 that potentially influence protein functions are observed at significantly different frequencies in different comparison groups. Protein structure modeling revealed that many non-synonymous SNVs have a deleterious effect on protein stability, structure and function. Mutational profiling at gene- and SNV-level revealed differential patterns within each breast cancer comparison group, and the gene signatures correlate with expected prognostic characteristics of breast cancer classes. Some of the genes and SNVs identified in this study show high promise and are worthy of further investigation by experimental studies. PMID:25803781

Li, You; Wang, Xiaosheng; Vural, Suleyman; Mishra, Nitish K.; Cowan, Kenneth H.; Guda, Chittibabu

2015-01-01

282

Mutation in the CYP21B gene (Ile-172. -->. Asn) causes steroid 21-hydroxylase deficiency  

SciTech Connect

Steroid 21-hydroxylase deficiency is the most common cause of congenital adrenal hyperplasia. It results from a deficiency in a specific cytochrome P450, P450c21 (P450XXIA). The gene encoding this protein (CYP21B) and a closely linked pseudogene (CYP21A) are located in the HLA complex on chromosome 6p. Many mutant alleles are associated with deletions of CYP21B; the authors report the cloning and characterization of a nondeleted mutant CYP21B gene. This mutant gene is expressed on transfection into mouse Y1 adrenal cells, producing mRNA levels similar to those seen after transfection of the normal CYP21B gene. In codon 172 of the mutant gene, the normal codon ATC, encoding isoleucine, has been changed to AAC, encoding asparagine. This mutation is normally present in the CYP21A pseudogene, so that it may have been transferred to the mutant CYP21B gene by gene conversion. Hybridization of oligonucleotide probes corresponding to this and two other mutations normally present in CYP21A demonstrated that 4 out of 20 patients carried the codon 172 mutation; in one of these patients, the mutation was present as part of a larger gene conversion involving at least exons 3-6. Gene conversion may be a frequent cause of 21-hydroxylase deficiency.

Amor, M.; Parker, K.L.; Globerman, H.; New, M.I.; White, P.C.

1988-03-01

283

Mutational landscape of gingivo-buccal oral squamous cell carcinoma reveals new recurrently-mutated genes and molecular subgroups  

PubMed Central

Gingivo-buccal oral squamous cell carcinoma (OSCC-GB), an anatomical and clinical subtype of head and neck squamous cell carcinoma (HNSCC), is prevalent in regions where tobacco-chewing is common. Exome sequencing (n=50) and recurrence testing (n=60) reveals that some significantly and frequently altered genes are specific to OSCC-GB (USP9X, MLL4, ARID2, UNC13C and TRPM3), while some others are shared with HNSCC (for example, TP53, FAT1, CASP8, HRAS and NOTCH1). We also find new genes with recurrent amplifications (for example, DROSHA, YAP1) or homozygous deletions (for example, DDX3X) in OSCC-GB. We find a high proportion of C>G transversions among tobacco users with high numbers of mutations. Many pathways that are enriched for genomic alterations are specific to OSCC-GB. Our work reveals molecular subtypes with distinctive mutational profiles such as patients predominantly harbouring mutations in CASP8 with or without mutations in FAT1. Mean duration of disease-free survival is significantly elevated in some molecular subgroups. These findings open new avenues for biological characterization and exploration of therapies. PMID:24292195

Maitra, Arindam; Biswas, Nidhan K.; Amin, Kishore; Kowtal, Pradnya; Kumar, Shantanu; Das, Subrata; Sarin, Rajiv; Majumder, Partha P.; Bagchi, I; Bairagya, B. B.; Basu, A.; Bhan, M. K.; Chaturvedi, P.; Das, D.; D'Cruz, A.; Dhar, R.; Dutta, D.; Ganguli, D.; Gera, P.; Gupta, T.; Mahapatra, S.; Mujawar, M. H. K.; Mukherjee, S.; Nair, S.; Nikam, S.; Nobre, M.; Patil, A.; Patra, S.; Rama-Gowtham, M.; Rao, T. S.; Roy, B.; Roychowdhury, B.; Sarkar, D.; Sarkar, S.; Sarkar-Roy, N.; Sutradhar, D.

2013-01-01

284

Non-classical hereditary hemochromatosis in Portugal: novel mutations identified in iron metabolism-related genes.  

PubMed

The most frequent genotype associated with Hereditary hemochromatosis is the homozygosity for C282Y, a common HFE mutation. However, other mutations in HFE, transferrin receptor 2 (TFR2), hemojuvelin (HJV) and hepcidin (HAMP) genes, have also been reported in association with this pathology. A mutational analysis of these genes was carried out in 215 Portuguese iron-overloaded individuals previously characterized as non-C282Y or non-H63D homozygous and non-compound heterozygous. The aim was to determine the influence of these genes in the development of iron overload phenotypes in our population. Regarding HFE, some known mutations were found, as S65C and E277K. In addition, three novel missense mutations (L46W, D129N and Y230F) and one nonsense mutation (Y138X) were identified. In TFR2, besides the I238M polymorphism and the rare IVS5 -9T-->A mutation, a novel missense mutation was detected (F280L). Concerning HAMP, the deleterious mutation 5'UTR -25G-->A was found once, associated with Juvenile Hemochromatosis. In HJV, the A310G polymorphism, the novel E275E silent alteration and the novel putative splicing mutation (IVS2 +395C-->G) were identified. In conclusion, only a few number of mutations which can be linked to iron overload was found, revealing their modest contribution for the development of this phenotype in our population, and suggesting that their screening in routine diagnosis is not cost-effective. PMID:18762941

Mendes, Ana Isabel; Ferro, Ana; Martins, Rute; Picanço, Isabel; Gomes, Susana; Cerqueira, Rute; Correia, Manuel; Nunes, António Robalo; Esteves, Jorge; Fleming, Rita; Faustino, Paula

2009-03-01

285

A bacterial model for expression of mutations in the human ornithine transcarbamylase (OTC) gene  

SciTech Connect

OTC is a mitochondrial enzyme catalyzing the formation of citrulline from carbamyl phosphate and ornithine. X-linked deficiency of OTC is the most prevalent genetic defect of ureagenesis. Mutations and polymorphisms in the OTC gene identified in deficient patients have indicated the occurrence of many family-specific, unique alleles. Due to the low frequency of recurrent mutations, distinguishing between deleterious mutations and polymorphisms is difficult. Using a human OTC gene containing plasmid driven by a tac promoter, we have devised a simple and efficient method for expressing mutations in the mature human OTC enzyme. To demonstrate this method, PCR engineered site-directed mutagenesis was employed to generated cDNA fragments which contained either the R151Q or R277W known mutations found in patients with neonatal and late-onset OTC deficiency, respectively. The normal allele for each mutation was also generated by an identical PCR procedure. Digestion with Bgl II- and Sty I-generated mutant and normal replacement cassettes containing the respective mutant and wild type sequences. Upon transformation of JM109 E.coli cells, OTC enzymatic activity was measured at log and stationary phases of growth using a radiochromatographic method. The R141Q mutation abolished enzymatic activity (<0.02% of normal), whereas the R277W mutation expressed partial activity (2.3% of normal). In addition, a PCR-generated mutation, A280V, resulted in 73% loss of catalytic activity. This OTC expression system is clinically applicable for distinguishing between mutations and polymorphisms, and it can be used to investigate the effects of mutations on various domains of the OTC gene.

Tuchman, M.; McCann, M.T.; Qureshi, A.A. [Univ. of Minnesota, Mineapolis (United States)

1994-09-01

286

Screening of C-kit gene Mutation in Acute Myeloid Leukaemia in Northern India  

PubMed Central

Background Acute Myeloid Leukaemia (AML) is a cancer of blood-forming cells in bone marrow. C-kit gene is a Receptor Tyrosine Kinase class III (RTK) that is expressed by early hematopoietic progenitor cells and plays an important role in hematopoietic stem cell proliferation, differentiation and survival. It is known that c-kit is a proto-oncogene and the activating c-kit mutations are likely to contribute in the development of leukaemia in humans. Exon 11 of c-Kit gene is the frequent site for mutations in different kinds of tumours. Methods In order to determine the frequency and prevalence of exon 11 mutations in 51 AML cases, we have done polymerase chain reaction-single-strand conformational polymorphism followed by direct DNA sequencing. Results The c-kit mutations in exon 11 were detected in 15.68% (8/51) in AML cases. We have detected totally ten missense mutations in eight AML cases those include Lys550Asn, Tyr568Ser, Ile571Leu, Tyr578Pro, Trp582Ser and Arg588Met and novel missense mutations at codons Ile563Lys and Val569Leu. Mutations at codons Ile571Leu and Trp582Ser was found in two independent cases. Conclusion The presence of c-kit mutations in our study adds to investigative spectrum of AML cases. Since the c-kit mutations are seen in other malignancies, mutations in exon 11 of the c-kit gene might be involve in pathogenesis and represent useful predictive genetic marker in AML. Further studies in larger group of cases possibly will be required to determine the prognostic implications and to investigate how these mutations are co-related to the progression and pathogenesis of AML.

Hussain, SR; Raza, ST; Babu, SG; Singh, P; Naqvi, H; Mahdi, F

2012-01-01

287

Heteroduplex analysis of the dystrophin gene: Application to point mutation and carrier detection  

SciTech Connect

Approximately one-third of Duchenne muscular dystrophy patients have undefined mutations in the dystrophin gene. For carrier and prenatal studies in families without detectable mutations, the indirect restriction fragment length polymorphism linkage approach is used. Using a multiplex amplification and heteroduplex analysis of dystrophin exons, the authors identified nonsense mutations in two DMD patients. Although the nonsense mutations are predicted to severely truncate the dystrophin protein, both patients presented with mild clinical courses of the disease. As a result of identifying the mutation in the affected boys, direct carrier studies by heteroduplex analysis were extended to other relatives. The authors conclude that the technique is not only ideal for mutation detection but is also useful for diagnostic testing. 29 refs., 4 figs.

Prior, T.W.; Papp, A.C.; Snyder, P.J.; Sedra, M.S.; Western, L.M.; Bartolo, C.; Mendell, J.R. [Ohio State Univ., Columbus, OH (United States); Moxley, R.T. [Univ. of Rochester Medical Center, NY (United States)

1994-03-01

288

Unlinked Noncomplementation: Isolation of New Conditional-Lethal Mutations in Each of the Tubulin Genes of Saccharomyces Cerevisiae  

PubMed Central

Mutations in genes of Saccharomyces cerevisiae that code for proteins that interact with ?-tubulin were sought by screening for unlinked mutations that fail to complement mutations in the single ?-tubulin-encoding gene (TUB2). Among the first three noncomplementing mutations examined, two are linked to TUB2 while one is unlinked. The unlinked mutation was shown to be a conditional-lethal allele of the major ?-tubulin-encoding gene (TUB1) and represents the first such mutation in that gene. The tub1-1 mutation itself causes a cold-sensitive cell-cycle arrest, and confers supersensitivity to the antimicrotubule drug benomyl. These phenotypes occur in the presence of a wild-type copy of the minor ?-tubulin-encoding gene, TUB3; the combination of tub1-1 and a tub3 null mutation is inviable in haploids. Through further application of this method, new mutations in TUB2 and TUB3 were isolated as unlinked noncomplementers of tub1-1. The noncomplementation between tub1 and tub2 mutations is gene specific and allele specific, suggesting that the phenotype is due to an interaction at the protein level. We conclude that isolation of unlinked noncomplementing mutations is likely to be a generally useful method for isolating mutations in interacting gene products. PMID:3294100

Stearns, T.; Botstein, D.

1988-01-01

289

A Novel Fibrillin 1 Gene Mutation Leading to Marfan Syndrome with Minimal Cardiac Features  

PubMed Central

Marfan syndrome is an autosomal dominant disorder of the connective tissue, characterized by early development of thoracic aortic aneurysms and/or dissections, accompanied by ocular and/or skeletal involvement, and is caused by mutations in the fibrillin 1 (FBN1) gene. We report on a patient with ectopia lentis and a nonprogressive aortic root dilatation who presented with a novel mutation affecting a conserved cysteine residue present in a calcium-binding epidermal growth factor-like domain of FBN1 (ENSP00000325527, p.Cys538Phe; Chr15:48,805,751 G>T), as revealed by complete sequencing of the FBN1 gene exons and flanking sequences. Identification of the mutation led to genetic screening of apparently asymptomatic family members, allowing the detection of characteristic ocular phenotypes in the absence of typical cardiac Marfan features. This finding stresses the importance of genetic screening of asymptomatic relatives for FBN1 gene mutation carriers. PMID:25337071

Martínez-Quintana, E; Rodríguez-González, F; Garay-Sánchez, P; Tugores, A

2014-01-01

290

Exome Sequencing Reveals Cubilin Mutation as a Single-Gene Cause of Proteinuria  

PubMed Central

In two siblings of consanguineous parents with intermittent nephrotic-range proteinuria, we identified a homozygous deleterious frameshift mutation in the gene CUBN, which encodes cubulin, using exome capture and massively parallel re-sequencing. The mutation segregated with affected members of this family and was absent from 92 healthy individuals, thereby identifying a recessive mutation in CUBN as the single-gene cause of proteinuria in this sibship. Cubulin mutations cause a hereditary form of megaloblastic anemia secondary to vitamin B12 deficiency, and proteinuria occurs in 50% of cases since cubilin is coreceptor for both the intestinal vitamin B12-intrinsic factor complex and the tubular reabsorption of protein in the proximal tubule. In summary, we report successful use of exome capture and massively parallel re-sequencing to identify a rare, single-gene cause of nephropathy. PMID:21903995

Ovunc, Bugsu; Otto, Edgar A.; Vega-Warner, Virginia; Saisawat, Pawaree; Ashraf, Shazia; Ramaswami, Gokul; Fathy, Hanan M.; Schoeb, Dominik; Chernin, Gil; Lyons, Robert H.; Yilmaz, Engin

2011-01-01

291

A novel fibrillin 1 gene mutation leading to marfan syndrome with minimal cardiac features.  

PubMed

Marfan syndrome is an autosomal dominant disorder of the connective tissue, characterized by early development of thoracic aortic aneurysms and/or dissections, accompanied by ocular and/or skeletal involvement, and is caused by mutations in the fibrillin 1 (FBN1) gene. We report on a patient with ectopia lentis and a nonprogressive aortic root dilatation who presented with a novel mutation affecting a conserved cysteine residue present in a calcium-binding epidermal growth factor-like domain of FBN1 (ENSP00000325527, p.Cys538Phe; Chr15:48,805,751 G>T), as revealed by complete sequencing of the FBN1 gene exons and flanking sequences. Identification of the mutation led to genetic screening of apparently asymptomatic family members, allowing the detection of characteristic ocular phenotypes in the absence of typical cardiac Marfan features. This finding stresses the importance of genetic screening of asymptomatic relatives for FBN1 gene mutation carriers. PMID:25337071

Martínez-Quintana; Rodríguez-González; Garay-Sánchez; Tugores

2014-08-01

292

Mutations in the EXT1 and EXT2 genes in hereditary multiple exostoses.  

PubMed Central

Hereditary multiple exostoses (EXT; MIM 133700) is an autosomal dominant bone disorder characterized by the presence of multiple benign cartilage-capped tumors (exostoses). Besides suffering complications caused by the pressure of these exostoses on the surrounding tissues, EXT patients are at an increased risk for malignant chondrosarcoma, which may develop from an exostosis. EXT is genetically heterogeneous, and three loci have been identified so far: EXT1, on chromosome 8q23-q24; EXT2, on 11p11-p12; and EXT3, on the short arm of chromosome 19. The EXT1 and EXT2 genes were cloned recently, and they were shown to be homologous. We have now analyzed the EXT1 and EXT2 genes, in 26 EXT families originating from nine countries, to identify the underlying disease-causing mutation. Of the 26 families, 10 families had an EXT1 mutation, and 10 had an EXT2 mutation. Twelve of these mutations have never been described before. In addition, we have reviewed all EXT1 and EXT2 mutations reported so far, to determine the nature, frequency, and distribution of mutations that cause EXT. From this analysis, we conclude that mutations in either the EXT1 or the EXT2 gene are responsible for the majority of EXT cases. Most of the mutations in EXT1 and EXT2 cause premature termination of the EXT proteins, whereas missense mutations are rare. The development is thus mainly due to loss of function of the EXT genes, consistent with the hypothesis that the EXT genes have a tumor- suppressor function. PMID:9463333

Wuyts, W; Van Hul, W; De Boulle, K; Hendrickx, J; Bakker, E; Vanhoenacker, F; Mollica, F; Lüdecke, H J; Sayli, B S; Pazzaglia, U E; Mortier, G; Hamel, B; Conrad, E U; Matsushita, M; Raskind, W H; Willems, P J

1998-01-01

293

Mutations in the consensus helicase domains of the Werner syndrome gene  

SciTech Connect

Werner syndrome (WS) is an autosomal recessive disease with a complex phenotype that is suggestive of accelerated aging. WS is caused by mutations in a gene, WRN, that encodes a predicted 1,432-amino-acid protein with homology to DNA and RNA helicases. Previous work identified four WS mutations in the 3{prime} end of the gene, which resulted in predicted truncated protein products of 1,060-1,247 amino acids but did not disrupt the helicase domain region (amino acids 569-859). Here, additional WS subjects were screened for mutations, and the intron-exon structure of the gene was determined. A total of 35 exons were defined, with the coding sequences beginning in the second exon. Five new WS mutations were identified: two nonsense mutations at codons 369 and 889; a mutation at a splice-junction site, resulting in a predicted truncated protein of 760 amino acids; a 1-bp deletion causing a frameshift; and a predicted truncated protein of 391 amino acids. Another deletion is >15 kb of genomic DNA, including exons 19-23; the predicted protein is 1,186 amino acids long. Four of these new mutations either partially disrupt the helicase domain region or result in predicted protein products completely missing the helicase region. These results confirm that mutations in the WRN gene are responsible for WS. Also, the location of the mutations indicates that the presence or absence of the helicase domain does not influence the WS phenotype and suggests that WS is the result of complete loss of function of the WRN gene product. 63 refs., 1 fig., 5 tabs.

Yu, Chang-En; Oshima, Junko; Wijsman, E.M. [Univ. of Washington, Seattle, WA (United States)] [and others

1997-02-01

294

Dominant lethal mutations in the plasma membrane H(+)-ATPase gene of Saccharomyces cerevisiae.  

PubMed Central

The plasma membrane H(+)-ATPase of Saccharomyces cerevisiae is an essential protein that is required to establish cellular membrane potential and maintain a normal internal pH. An Asp-378 to Asn substitution at the residue phosphorylated during catalysis is dominant lethal when the pma1-D378N mutation is expressed along with a wild-type plasma membrane H(+)-ATPase (PMA1) gene. Several mutations in the first two putative transmembrane domains are also dominant lethal. However, these dominant lethal mutants often appear to be innocuous, because they are frequently lost by gene conversion to the wild-type sequence during the process of introducing the mutant sequence and subsequently removing the wild-type gene. Loss of the mutation by gene conversion does not occur while introducing recessive lethal mutations. Cells carrying the wild-type PMA1 gene on the chromosome and a dominant lethal mutation under the control of a GAL1 promoter on a centromere-containing plasmid exhibit a galactose-dependent lethality. Indirect immunofluorescence staining using anti-Pma1 antibodies shows that induction of dominant lethal PMA1 mutations leads to the accumulation of a number of intensely staining cytoplasmic structures that are not coincident with the nucleus and its immediately surrounding endoplasmic reticulum. These structures also accumulate the endoplasmic reticulum protein Kar2. Expression of the dominant lethal protein also prevents transport of the wild-type ATPase to the plasma membrane. Images PMID:7937988

Harris, S L; Na, S; Zhu, X; Seto-Young, D; Perlin, D S; Teem, J H; Haber, J E

1994-01-01

295

Mutational heterogeneity in cancer and the search for new cancer genes  

PubMed Central

Major international projects are now underway aimed at creating a comprehensive catalog of all genes responsible for the initiation and progression of cancer. These studies involve sequencing of matched tumor–normal samples followed by mathematical analysis to identify those genes in which mutations occur more frequently than expected by random chance. Here, we describe a fundamental problem with cancer genome studies: as the sample size increases, the list of putatively significant genes produced by current analytical methods burgeons into the hundreds. The list includes many implausible genes (such as those encoding olfactory receptors and the muscle protein titin), suggesting extensive false positive findings that overshadow true driver events. Here, we show that this problem stems largely from mutational heterogeneity and provide a novel analytical methodology, MutSigCV, for resolving the problem. We apply MutSigCV to exome sequences from 3,083 tumor-normal pairs and discover extraordinary variation in (i) mutation frequency and spectrum within cancer types, which shed light on mutational processes and disease etiology, and (ii) mutation frequency across the genome, which is strongly correlated with DNA replication timing and also with transcriptional activity. By incorporating mutational heterogeneity into the analyses, MutSigCV is able to eliminate most of the apparent artefactual findings and allow true cancer genes to rise to attention. PMID:23770567

Kryukov, Gregory V.; Cibulskis, Kristian; Sivachenko, Andrey; Carter, Scott L.; Stewart, Chip; Mermel, Craig H.; Roberts, Steven A.; Kiezun, Adam; Hammerman, Peter S.; McKenna, Aaron; Drier, Yotam; Zou, Lihua; Ramos, Alex H.; Pugh, Trevor J.; Stransky, Nicolas; Helman, Elena; Kim, Jaegil; Sougnez, Carrie; Ambrogio, Lauren; Nickerson, Elizabeth; Shefler, Erica; Cortés, Maria L.; Auclair, Daniel; Saksena, Gordon; Voet, Douglas; Noble, Michael; DiCara, Daniel; Lin, Pei; Lichtenstein, Lee; Heiman, David I.; Fennell, Timothy; Imielinski, Marcin; Hernandez, Bryan; Hodis, Eran; Baca, Sylvan; Dulak, Austin M.; Lohr, Jens; Landau, Dan-Avi; Wu, Catherine J.; Melendez-Zajgla, Jorge; Hidalgo-Miranda, Alfredo; Koren, Amnon; McCarroll, Steven A.; Mora, Jaume; Crompton, Brian; Onofrio, Robert; Parkin, Melissa; Winckler, Wendy; Ardlie, Kristin; Gabriel, Stacey B.; Roberts, Charles W. M.; Biegel, Jaclyn A.; Stegmaier, Kimberly; Bass, Adam J.; Garraway, Levi A.; Meyerson, Matthew; Golub, Todd R.; Gordenin, Dmitry A.; Sunyaev, Shamil

2014-01-01

296

Molecular surveillance of mutations in dihydrofolate reductase and dihydropteroate synthase genes of Plasmodium falciparum in Ethiopia.  

PubMed

Point mutations in the genes for dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) of Plasmodium falciparum isolates are associated with sulfadoxine/pyrimethamine (SP) treatment failure, respectively. This study was conducted to assess the prevalence of SP resistance in P. falciparum isolates collected at the Jimma Health Center in southwestern Ethiopia. In this study, the genetic profile of P. falciparum isolates with respect to DHFR and DHPS genes was assessed in 124 individuals. The prevalence of single, double, and multiple mutations in these genes was calculated. The sequence profile showed that all samples carried a double mutation at the positions 51 and 108 (I51N108) in the DHFR gene. Sixty-seven (54.03%) of the isolates had an additional third mutation at position 59, resulting in the triple mutant I51R59N108. All isolates carried mutations G437 and E540 in the DHPS gene. Two isolates (1.61%) had additional mutations at codon 581 (A581). PMID:16354825

Gebru-Woldearegai, Tamirat; Hailu, Asrat; Grobusch, Martin P; Kun, Jürgen F J

2005-12-01

297

Mutations of the tyrosinase gene in Indo-Pakistani patients with type I (tyrosinase-deficient) oculocutaneous albinsm (OCA)  

SciTech Connect

Oculocutaneous albinism (OCA) is a group of autosomal recessive disorders characterized by deficient synthesis of melanin pigment. Type I (tyrosinase-deficient) OCA results from mutations of the tyrosinase gene (TYR gene) encoding tyrosinase, the enzyme that catalyzes the first two steps of melanin biosynthesis. Mutations of the TYR gene have been identified in a large number of patients, most of Caucasian ethnic origin, with various forms of type I OCA. The authors present an analysis of the TYR gene in eight Indo-Pakistani patients with type I OCA. The authors describe four novel TYR gene mutations and a fifth mutation previously observed in a Caucasian patient. 16 refs., 6 figs.

Tripathi, R.K.; Droetto, S.; Strunk, K.M.; Holmes, S.A.; Spritz, R.A. (Univ. of Wisconsin, Madison, WI (United States)); Bundey, S.; Musarella, M.A.

1993-12-01

298

Five novel CNGB3 gene mutations in Polish patients with achromatopsia  

PubMed Central

Purpose To identify the genetic basis of achromatopsia (ACHM) in four patients from four unrelated Polish families. Methods In this study, we investigated probands with a clinical diagnosis of ACHM. Ophthalmologic examinations, including visual acuity testing, color vision testing, and full-field electroretinography (ERG), were performed in all patients (with the exception of patient p4, who had no ERG). Direct DNA sequencing encompassing the entire coding region of the CNGB3 gene, eight exons of the GNAT2 gene, and exons 5–7 of the CNGA3 gene was performed. Segregation analysis for the presence and independent inheritance of two mutant alleles was performed in the three families available for study. Results All patients showed typical achromatopsia signs and symptoms. Sequencing helped detect causative changes in the CNGB3 gene in all probands. Eight different mutations were detected in the CNGB3 gene, including five novel mutations: two splice site mutations (c.1579–1G>A and c.494–2A>T), one nonsense substitution (c.1194T>G), and two frame-shift mutations (c.393_394delGCinsTCCTGGTGA and c.1366delC). We also found three mutations: one splice site (c.1578+1G>A) and two frame-shift deletions that had been previously described (c.819_826del and c.1148delC). All respective parents were shown to be heterozygous carriers for the mutation detected in their children. Conclusions The present study reports five novel mutations in the CNGB3 gene, and thus broadens the spectrum of probably pathogenic mutations associated with ACHM. Together with molecular data, we provide a brief clinical description of the affected individuals. PMID:25558176

Kohl, Susanne; Baumann, Britta; Walczak-Sztulpa, Joanna; Wicher, Katarzyna; Skorczyk-Werner, Anna; Krawczynski, Maciej R.

2014-01-01

299

Mutations in SOX9, the gene responsible for campomelic dysplasia and autosomal sex reversal  

SciTech Connect

Campomelic dysplasia (CD) is a skeletal malformation syndrome frequently accompanied by 46,XY sex reversal. A mutation-screening strategy using SSCP was employed to identify mutations in SOX9, the chromosome 17q24 gene responsible for CD and autosomal sex reversal in man. We have screened seven CD patients with no cytologically detectable chromosomal aberrations and two CD patients with chromosome 17 rearrangements for mutations in the entire open reading frame of SOX9. Five different mutations have been identified in six CD patients: two missense mutations in the SOX9 putative DNA binding domain (high mobility group, or HMG, box); three frameshift mutations and a splice-acceptor mutation. An identical frameshift mutation is found in two unrelated 46,XY patients, one exhibiting a male phenotype and the other displaying a female phenotype (XY sex reversal). All mutations found affect a single allele, which is consistent with a dominant mode of inheritance. No mutations were found in the SOX9 open reading frame of two patients with chromosome 17q rearrangements, suggesting that the translocations affect SOX9 expression. These findings are consistent with the hypothesis that CD results from haploinsufficiency of SOX9. 27 refs., 3 figs., 3 tabs.

Kwok, C.; Weller, P.A.; Guioli, S. [St. George`s Hospital Medical School, London (United Kingdom)] [and others

1995-11-01

300

Phenotypic involvement in females with the FMR1 gene mutation.  

PubMed

Fragile X syndrome is the most common from of inherited mental retardation. Approximately half of females with the full mutation have significant cognitive deficits, whereas females with the premutation do not. Phenotypic effects seen in 281 females (IQs from 64 to 139) were analyzed. Results showed that females with the full mutation differ significantly from controls on selected anthropometric measurements, physical index score, and various behavioral features. Females with the premutation differed significantly from controls in regards to a few anthropometric measurements and the physical index score but not in behavioral features. These results suggest that phenotypic effects of the FMR1 mutation are not only common in females with the full mutation, but in females with the premutation as well. PMID:9606468

Riddle, J E; Cheema, A; Sobesky, W E; Gardner, S C; Taylor, A K; Pennington, B F; Hagerman, R J

1998-05-01

301

Different Gene Mutations May Determine Severity, Type of Autism  

MedlinePLUS

... 22, 2014 Related MedlinePlus Pages Autism Spectrum Disorder Genes and Gene Therapy MONDAY, Dec. 22, 2014 (HealthDay News) -- Different types ... reserved. More Health News on: Autism Spectrum Disorder Genes and Gene Therapy Recent Health News Page last updated on 23 ...

302

Three Novel Missense Mutations within the LHX4 Gene Are Associated with Variable Pituitary Hormone Deficiencies  

PubMed Central

Context: The LHX4 LIM-homeodomain transcription factor has essential roles in pituitary gland and nervous system development. Heterozygous mutations in LHX4 are associated with combined pituitary hormone deficiency. Objectives: Our objectives were to determine the nature and frequency of LHX4 mutations in patients with pituitary hormone deficiency and to examine the functional outcomes of observed mutations. Design: The LHX4 gene sequence was determined from patient DNA. The biochemical and gene regulatory properties of aberrant LHX4 proteins were characterized using structural predictions, pituitary gene transcription assays, and DNA binding experiments. Patients: A total of 253 patients from 245 pedigrees with GH deficiency and deficiency of at least one additional pituitary hormone was included in the study. Results: In five patients, three types of heterozygous missense mutations in LHX4 that result in substitution of conserved amino acids were identified. One substitution is between the LIM domains (R84C); the others are in the homeodomain (L190R; A210P). The patients have GH deficiency; some also display reductions in TSH, LH, FSH, or ACTH, and aberrant pituitary morphology. Structural models predict that the aberrant L190R and A210P LHX4 proteins would have impaired DNA binding and gene activation properties. Consistent with these models, EMSAs and transfection experiments using pituitary gene promoters demonstrate that whereas the R84C form has reduced activity, the L190R and A210P proteins are inactive. Conclusions: LHX4 mutations are a relatively rare cause of combined pituitary hormone deficiency. This report extends the range of phenotypes associated with LHX4 gene mutations and describes three novel exonic mutations in the gene. PMID:18073311

Pfaeffle, Roland W.; Hunter, Chad S.; Savage, Jesse J.; Duran-Prado, Mario; Mullen, Rachel D.; Neeb, Zachary P.; Eiholzer, Urs; Hesse, Volker; Haddad, Nadine G.; Stobbe, Heike M.; Blum, Werner F.; Weigel, Johannes F. W.; Rhodes, Simon J.

2008-01-01

303

Three Novel Mutations in Porphobilinogen Deaminase Gene Identified in Russian Patients with Acute Intermittent Porphyria  

Microsoft Academic Search

Porphobilinogen deaminase (PBGD) is a key enzyme of the heme biosynthetic pathway. Defects in the PBGD gene lead to an autosomal dominant disease, acute intermittent porphyria (AIP). Almost all AIP patients with rare exceptions are heterozygous for the defective gene. To date, at least 160 different mutations causing AIP are identified. Extensive investigations along this line are conducted in many

V. L. Surin; A. V. Luk'yanenko; I. V. Karpova; A. V. Misyurin; Ya. S. Pustovoit; A. V. Pivnik

2001-01-01

304

Gene-targeting studies of mammalian behavior: is it the mutation or the background genotype?  

Microsoft Academic Search

Gene targeting to create null mutations in mice is a powerful new tool in biology which will allow the molecular dissection of complex phenotypes such as mammalian brain function, and learning and memory. However, the attempt to interpret the phenotypical changes which arise in null-mutant mice is subject to several caveats. For example, the ability to disrupt a single gene

Robert Gerlai

1996-01-01

305

Mutation screening of the ARX gene in patients with autism Pauline Chaste  

E-print Network

spectrum of disorders, including nonsyndromic X-linked mental retardation, sometimes associated the ARX gene in 226 male patients with autism spectrum disorders and mental retardation; 42 that mutations in the ARX gene are very rare in autism. Key words: X chromosome, mental retardation, epilepsy

Paris-Sud XI, Université de

306

Molecular pathways of oligodendrocyte apoptosis revealed by mutations in the proteolipid protein gene  

Microsoft Academic Search

A decade after the genetic link was established between mutations in the proteo- lipid protein gene and two leukodystrophies, Pelizaeus-Merzbacher disease and spastic paraplegia, the molecular mechanisms underlying pathogenesis are beginning to come to light. Data from animal models of these diseases suggest that the absence of proteolipid protein gene products in the central nervous system confers a relatively mild

Cherie Southwood; Alexander Gow

2001-01-01

307

MOLECULAR ANALYSIS OF MUTATIONS INDUCED BY MUTAGENS IN THE TK GENE OF MOUSE LYMPHOMA CELLS  

EPA Science Inventory

MOLECULAR ANALYSIS OF MUTATIONS INDUCED BY BROMATE AND N- ETHYL-N-NITROSOUREA IN THE TK GENE OF MOUSE L YMPHOMA CELLS The mouse lymphoma assay is widely used to identify chemical mutagens The Tk +1- gene located on an autosome in mouse lymphoma cells may recover a wide ra...

308

Point mutations of ras genes in human adrenal cortical tumors: Absence in adrenocortical hyperplasia  

Microsoft Academic Search

Point mutations of ras genes (K-, H-, and N-ras) at codons 12, 13, and 61 and of the Gi2a gene at codons 179 and 205, were studied in 56 primary adrenal cortical tumors and 6 adrenal cortical hyperplasias. Of 56 tumors, 24 were carcinomas and 32 were benign. The 24 carcinomas and 20 of the benign tumors were from American

Tohru Yashiro; Hisato Hara; Noreen C. Fulton; Takao Obara; Edwin L. Kaplan

1994-01-01

309

Loss of heterozygosity and K- ras gene mutations in gastric cancer  

Microsoft Academic Search

In order to identify relevant genetic lesions in gastric carcinoma, we searched for tumor suppressor gene inactivation and K-ras gene mutations by analyzing tumor and control DNAs from 34 patients. These were from an epidemiologically defined area of Italy characterized by one of the world's highest incidences of stomach cancer. Allele losses were investigated by the Southern blotting procedure at

G. N. Ranzani; B. Renault; N. S. Pellegata; P. Fattorini; E. Magni; F. Bacci; D. Amadori

1993-01-01

310

Study on the Evolution of Genes Mutation Related With Gastrointestinal Stromal Tumors  

ClinicalTrials.gov

Full Gene Sequences of c-KIT?PDGFRA and DOG1 Are Analyzed With the Screening-sequencing Approach; Investigate the Characteristics and Variations Associated With the Different Gene Mutations of c-KIT?PDGFRA and DOG1 in GIST Patients

2012-01-05

311

Targeted sequencing using a 47 gene multiple myeloma mutation panel (M(3) P) in -17p high risk disease.  

PubMed

We constructed a multiple myeloma (MM)-specific gene panel for targeted sequencing and investigated 72 untreated high-risk (del17p) MM patients. Mutations were identified in 78% of the patients. While the majority of studied genes were mutated at similar frequency to published literature, the prevalence of TP53 mutation was increased (28%) and no mutations were found in FAM46C. This study provides a comprehensive insight into the mutational landscape of del17p high-risk MM. Additionally, our work demonstrates the practical use of a customized sequencing panel, as an easy, cheap and fast approach to characterize the mutational profile of MM. PMID:25302557

Kortüm, Klaus M; Langer, Christian; Monge, Jorge; Bruins, Laura; Egan, Jan B; Zhu, Yuan X; Shi, Chang Xin; Jedlowski, Patrick; Schmidt, Jessica; Ojha, Juhi; Bullinger, Lars; Liebisch, Peter; Kull, Miriam; Champion, Mia D; Van Wier, Scott; Ahmann, Gregory; Rasche, Leo; Knop, Stefan; Fonseca, Rafael; Einsele, Hermann; Stewart, A Keith; Braggio, Esteban

2015-02-01

312

Targeted sequencing using a 47 gene multiple myeloma mutation panel (M3P) in -17p high risk disease  

PubMed Central

Summary We constructed a multiple myeloma (MM)-specific gene panel for targeted sequencing and investigated 72 untreated high-risk (del17p) MM patients. Mutations were identified in 78% of the patients. While the majority of studied genes were mutated at similar frequency to published literature, the prevalence of TP53 mutation was increased (28%) and no mutations were found in FAM46C. This study provides a comprehensive insight into the mutational landscape of del17p high-risk MM. Additionally, our work demonstrates the practical use of a customized sequencing panel, as an easy, cheap and fast approach to characterize the mutational profile of MM. PMID:25302557

Kortüm, Klaus M.; Langer, Christian; Monge, Jorge; Bruins, Laura; Egan, Jan B.; Zhu, Yuan X.; Shi, Chang Xin; Jedlowski, Patrick; Schmidt, Jessica; Ojha, Juhi; Bullinger, Lars; Liebisch, Peter; Kull, Miriam; Champion, Mia D.; Van Wier, Scott; Ahmann, Gregory; Rasche, Leo; Knop, Stefan; Fonseca, Rafael; Einsele, Hermann; Stewart, A Keith; Braggio, Esteban

2015-01-01

313

Mutation analysis of the IL36RN gene in 14 Japanese patients with generalized pustular psoriasis.  

PubMed

Generalized pustular psoriasis (GPP) is a rare, potentially life threatening, and aggressive form of psoriasis, which is characterized by sudden onset with repeated episodic skin inflammation leading to pustule formation. Familial GPP is known to be caused by recessively inherited mutations in the IL36RN gene, which encodes interleukin 36 receptor antagonist (IL-36Ra). In this article, we performed mutation analysis of the IL36RN gene in 14 Japanese patients with GPP, and identified mutations in two of these patients analyzed. One patient was compound heterozygous for mutations c.115+6T>C and c.368C>G (p.Thr123Arg), whereas the other carried compound heterozygous mutations c.28C>T (p.Arg10*) and c.115+6T>C in the IL36RN gene. Expression studies using total RNA from the patients' skin revealed that the mutation c.115+6T>C resulted in skipping of exon 3, leading to a frameshift and a premature termination codon (p.Arg10Argfs*1). The protein structure analysis suggested that the missense mutation p.Thr123Arg caused misfolding and instability of IL-36Ra protein. In vitro studies in cultured cells showed impaired expression of the p.Thr123Arg mutant IL-36Ra protein, which failed to antagonize the IL-36 signaling pathway. Our data further underscore the critical role of IL36RN in pathogenesis of GPP. PMID:22903787

Farooq, Muhammad; Nakai, Hiroyuki; Fujimoto, Atsushi; Fujikawa, Hiroki; Matsuyama, Asako; Kariya, Naoyuki; Aizawa, Atsuko; Fujiwara, Hiroshi; Ito, Masaaki; Shimomura, Yutaka

2013-01-01

314

Mutation Analysis of Mycobacterial rpoB Genes and Rifampin Resistance Using Recombinant Mycobacterium smegmatis  

PubMed Central

Rifampin is a major drug used to treat leprosy and tuberculosis. The rifampin resistance of Mycobacterium leprae and Mycobacterium tuberculosis results from a mutation in the rpoB gene, encoding the ? subunit of RNA polymerase. A method for the molecular determination of rifampin resistance in these two mycobacteria would be clinically valuable, but the relationship between the mutations and susceptibility to rifampin must be clarified before its use. Analyses of mutations responsible for rifampin resistance using clinical isolates present some limitations. Each clinical isolate has its own genetic variations in some loci other than rpoB, which might affect rifampin susceptibility. For this study, we constructed recombinant strains of Mycobacterium smegmatis carrying the M. leprae or M. tuberculosis rpoB gene with or without mutation and disrupted their own rpoB genes on the chromosome. The rifampin and rifabutin susceptibilities of the recombinant bacteria were measured to examine the influence of the mutations. The results confirmed that several mutations detected in clinical isolates of these two pathogenic mycobacteria can confer rifampin resistance, but they also suggested that some mutations detected in M. leprae isolates or rifampin-resistant M. tuberculosis isolates are not involved in rifampin resistance. PMID:22252831

Kai, Masanori; Makino, Masahiko

2012-01-01

315

The human ?2 glutamate receptor gene is not mutated in patients with spinocerebellar ataxia  

PubMed Central

The human glutamate receptor delta 2 gene (GRID2) shares 90% homology with the orthologous mouse gene. The mouse Grid2 gene is involved with functions of the cerebellum and spontaneous mutation of Grid2 leads to a spinocerebellar ataxia-like phenotype. To investigate whether such mutations occur in humans, we screened for mutations in the coding sequence of GRID2 in 24 patients with familial or sporadic spinocerebellar ataxia and in 52 normal controls. We detected no point mutations or insertion/deletion mutations in the 16 exons of GRID2. However, a polymorphic 4 nucleotide deletion (IVS5-121_-118 GAGT) and two single nucleotide polymorphisms (c.1251G>T and IVS14-63C>G) were identified. The frequency of these polymorphisms was similar between spinocerebellar ataxia patients and normal controls. These data indicate that spontaneous mutations do not occur in GRID2 and that the incidence of spinocerebellar ataxia in humans is not associated with GRID2 mutation or polymorphisms. PMID:25206761

Huang, Jinxiang; Lin, Aiyu; Dong, Haiyan; Wang, Chaodong

2014-01-01

316

Patched-one or smoothened gene mutations are infrequent in chondrosarcoma.  

PubMed

Constitutive hedgehog signaling has been implicated in the tumorigenesis of cartilaginous neoplasia; however, a common mutational mechanism remains unknown. Some tumors exhibiting hedgehog pathway activation such as basal cell cancer frequently harbor PATCHED-ONE (PTCH-1) or SMOOTHENED (SMO) gene mutations. We therefore asked whether mutations of the hedgehog receptor genes PTCH-1 or SMO occur in cartilage tumors. Singlestrand conformation polymorphism (SSCP) analysis with subsequent manual sequencing was performed to detect alterations of PTCH-1 and SMO in 46 cartilage tumors. SSCP detected five shifts in the PTCH-1 gene and two shifts in SMO. Direct DNA sequencing revealed the five shifts in PTCH-1 were caused by silent nucleotide alterations. The two SMO shifts were the result of the same missense mutation (783G>A) and occurred in one dedifferentiated chondrosarcoma and a synovial chondromatosis. The patient with chondromatosis also carried this same mutation in the germline. However, this mutation was also identified in leukocyte DNA from three of 127 (2.4%) control subjects without cartilage tumors, suggesting it may represent a rare SMO variant. Constitutive activation of the hedgehog signaling pathway in chondrosarcoma is rarely caused by PTCH-1 or SMO mutations. [corrected] PMID:18543049

Yan, Taiqiang; Angelini, Mark; Alman, Benjamin A; Andrulis, Irene L; Wunder, Jay S

2008-09-01

317

Mutation analysis and embryonic expression of the HLXB9 Currarino syndrome gene.  

PubMed Central

The HLXB9 homeobox gene was recently identified as a locus for autosomal dominant Currarino syndrome, also known as hereditary sacral agenesis (HSA). This gene specifies a 403-amino acid protein containing a homeodomain preceded by a very highly conserved 82-amino acid domain of unknown function; the remainder of the protein is not well conserved. Here we report an extensive mutation survey that has identified mutations in the HLXB9 gene in 20 of 21 patients tested with familial Currarino syndrome. Mutations were also detected in two of seven sporadic Currarino syndrome patients; the remainder could be explained by undetected mosaicism for an HLXB9 mutation or by genetic heterogeneity in the sporadic patients. Of the mutations identified in the 22 index patients, 19 were intragenic and included 11 mutations that could lead to the introduction of a premature termination codon. The other eight mutations were missense mutations that were significantly clustered in the homeodomain, resulting, in each patient, in nonconservative substitution of a highly conserved amino acid. All of the intragenic mutations were associated with comparable phenotypes. The only genotype-phenotype correlation appeared to be the occurrence of developmental delay in the case of three patients with microdeletions. HLXB9 expression was analyzed during early human development in a period spanning Carnegie stages 12-21. Signal was detected in the basal plate of the spinal cord and hindbrain and in the pharynx, esophagus, stomach, and pancreas. Significant spatial and temporal expression differences were evident when compared with expression of the mouse Hlxb9 gene, which may partly explain the significant human-mouse differences in mutant phenotype. PMID:10749657

Hagan, D M; Ross, A J; Strachan, T; Lynch, S A; Ruiz-Perez, V; Wang, Y M; Scambler, P; Custard, E; Reardon, W; Hassan, S; Nixon, P; Papapetrou, C; Winter, R M; Edwards, Y; Morrison, K; Barrow, M; Cordier-Alex, M P; Correia, P; Galvin-Parton, P A; Gaskill, S; Gaskin, K J; Garcia-Minaur, S; Gereige, R; Hayward, R; Homfray, T

2000-01-01

318

Iranian hereditary hemochromatosis patients: Baseline characteristics, laboratory data and gene mutations  

PubMed Central

Summary Background Hereditary hemochromatosis (HH) is the most common autosomal recessive disorder in white people, characterized by highly abnormal uptake of iron from the gastrointestinal tracts. Recently, mutation studies have focused to detect the genes responsible for HH. Material/Methods In this cross-sectional study, 12 HH patients were recruited, who were referred to Firoozgar Hospital, Tehran, Iran. In addition to the clinical assessments, a complete laboratory evaluation, imaging modalities, histopathologic assessment, atomic absorption spectrophotometry and gene mutation study were performed. The genetic study for HFE gene mutation was examined for all of the patients since 2006, while non-HFE mutation was conducted since December 2010 (only for 1 of them). Results Twelve patients were evaluated consisting of 11 men and 1 woman, with the mean age of 39.58±12.68 yr. The average of atomic iron loads was 13.25±4.83-fold higher than normal standards. Four patients had heterozygotic mutation of H63D (33.3%). There was no significant difference in either the iron load of liver (P=0.927) and heart (P=0.164) or serum concentration of ferritin (P=0.907) and TIBC (P=0.937) between the HFE-mutant and without HFE mutation HH cases. Conclusions In contrast to other studies, C282Y mutation was not detected in any of our Iranian HH patients. Heterozygotic mutations of H63D (HFE) and TFR2 (non-HFE) genes were found to be more common in these patients. Similar to previous reports, these mutations were not found to be significantly associated with severity of presentation in HH patients. PMID:23018356

Zamani, Farhad; Bagheri, Zohreh; Bayat, Maryam; Fereshtehnejad, Seyed-Mohammad; Basi, Ali; Najmabadi, Hossein; Ajdarkosh, Hossein

2012-01-01

319

Identification of new mutations in the NF2 tumor suppressor gene in schwannomas  

SciTech Connect

Neurofibromatosis type 2 (NF2) is a severe genetic disorder with an incidence of approximately 1 in 40,000 individuals and is characterized by the formation of multiple benign nervous system tumors. The clinical hallmark of NF2 is the bilateral occurrence of schwannomas on the eighth cranial nerve (vestibular schwannomas). Recently, it has been shown that loss or inactivation of a tumor suppressor gene located in chromosome band 22q12 is the molecular cause of NF2 tumorigenesis. Also, mutations in the NF2 gene have now been identified in patients with sporadic vestibular schwannomas (unilateral schwannomas). We have completed the screening of 80% of the NF2 coding sequence of DNA from 13 sporadic schwannomas and 2 schwannomas from NF2 patients. Using heteroduplex analysis and direct sequencing, we found 13 novel mutations located in 7 different exons with a small cluster (46% of the mutations) located in the central portion of the gene. All of the mutations were unique to single patients. In three tumors, both NF2 alleles were mutated. The types of mutations found include: small deletions ranging from 1 to 30 base pairs, nonsense mutations, a single missense mutation and a splice donor site alteration. It appears that small deletions are the most common type of NF2 gene mutation. We also have developed a dosage test based on quantitative PCR and hybridization with specific probes to detect the loss of heterozygosity. We found that 7 out of 15 schwannomas (47%) show loss of heterozygosity. We are currently extending the analysis to all of the NF2 exons and DNA from 60 additional schwannomas.

Guida, M.; Welling, B.; Prior, T.W. [Ohio State Univ., Columbus, OH (United States)

1994-09-01

320

Tay-Sachs disease-causing mutations and neutral polymorphisms in the Hex A gene.  

PubMed

Tay-Sachs disease is an autosomal recessive disorder affecting the central nervous system. The disorder results from mutations in the gene encoding the alpha-subunit of beta-hexosaminidase A, a lysosomal enzyme composed of alpha and beta polypeptides. Seventy-eight mutations in the Hex A gene have been described and include 65 single base substitutions, one large and 10 small deletions, and two small insertions. Because these mutations cripple the catalytic activity of beta-hexosaminidase to varying degrees, Tay-Sachs disease displays clinical heterogeneity. Forty-five of the single base substitutions cause missense mutations; 39 of these are disease causing, three are benign but cause a change in phenotype, and three are neutral polymorphisms. Six nonsense mutations and 14 splice site lesions result from single base substitutions, and all but one of the splice site lesions cause a severe form of Tay-Sachs disease. Eight frameshift mutations arise from six deletion- and two insertion-type lesions. One of these insertions, consisting of four bases within exon 11, is found in 80% of the carriers of Tay-Sachs disease from the Ashkenazi Jewish population, an ethnic group that has a 10-fold higher gene frequency for a severe form of the disorder than the general population. A very large deletion, 7.5 kilobases, including all of exon 1 and portions of DNA upstream and downstream from that exon, is the major mutation found in Tay-Sachs disease carriers from the French Canadian population, a geographic isolate displaying an elevated carrier frequency. Most of the other mutations are confined to single pedigrees. Identification of these mutations has permitted more accurate carrier information, prenatal diagnosis, and disease prognosis. In conjunction with a precise tertiary structure of the enzyme, these mutations could be used to gain insight into the structure-function relationships of the lysosomal enzyme. PMID:9090523

Myerowitz, R

1997-01-01

321

Mutations of the phenylalanine hydroxylase (PAH) gene in Brazilian patients with phenylketonuria.  

PubMed

In the present study, 115 Brazilian families with phenylketonuria (PKU), mainly from the Southeast of the country, were studied using three laboratory methods (DGGE, SSCP, and sequencing). All 13 exons of the PAH gene were analyzed, including the splicing sites and the promoter region. We identified 50 distinct mutations and characterized 91% of the mutant alleles. The five most prevalent mutations of the 50 mutations identified (50% of the PKU alleles) were IVS10nt-11G-->A (17.4%), followed by R261Q (12.2%), V388M (9.1%), R252W (6.5%), and R270K (4.8%). The other mutations were rare. The mutation spectrum included 10 novel mutations (IVS5nt-54A-->G, IVS6nt17G-->T, E205A, F240S, K274E, I318T, L321L, C357G, IVS11nt17G-->A, and S411X). To characterize the origin and distribution of the PAH alleles we determined the association between the detected mutations and the PCR/RFLP haplotypes and VNTR alleles located on the PAH gene. For those patients whose mutant alleles were detected, we calculated the correlation with pretreatment phenylalanine levels, thus establishing a genotype/phenotype correlation. The present results confirm the marked heterogeneity observed at the PAH locus and contribute to the understanding of the distribution and frequency of PKU mutations in the Brazilian population. PMID:11180595

Acosta, A; Silva, W; Carvalho, T; Gomes, M; Zago, M

2001-02-01

322

Novel VANGL1 Gene Mutations in 144 Slovakian, Romanian and German Patients with Neural Tube Defects.  

PubMed

Neural tube defects (NTDs) are a group of congenital malformations of the central nervous system occurring at an average rate of 1 per 1,000 human pregnancies worldwide. Numerous genetic and environmental factors are discussed to be relevant in their etiology. In mice, mutants in >200 genes including the planar cell polarity (PCP) pathway are known to cause NTDs, and recently, heterozygous mutations in the human VANGL1 gene have been described in a small subset of patients with NTDs. We performed a VANGL1 mutation analysis in 144 unrelated individuals with NTDs from Slovakia, Romania and Germany and identified 3 heterozygous missense mutations: c.613G>A (p.Gly205Arg) with an open spina bifida (lumbosacral meningomyelocele), c.557G>A (p.Arg186His) with a closed spina bifida (tethered cord and spinal lipoma) and c.518G>A (p.Arg173His) with an unknown NTD. The c.613G>A mutation was also found in a healthy sibling. None of the mutations were described previously. Findings support that heterozygous VANGL1 mutations represent hypomorphs or conditional mutants predisposing to NTDs and occur at a frequency of approximately 2.1% of open and closed spinal NTDs. The mutations (p.Arg173His, p.Arg186His, p.Gly205Arg) modified conserved regions of the VANGL1 protein and shared similarities with previously described mutants, providing further evidence for the presence of mutational hot spots in these patients. PMID:23326252

Bartsch, O; Kirmes, I; Thiede, A; Lechno, S; Gocan, H; Florian, I S; Haaf, T; Zechner, U; Sabova, L; Horn, F

2012-08-01

323

Comparison of droplet digital PCR and conventional quantitative PCR for measuring EGFR gene mutation  

PubMed Central

Early detection of epidermal growth factor receptor (EGFR) mutation, particularly EGFR T790M mutation, is of clinical significance. The aim of the present study was to compare the performances of amplification refractory mutation system-based quantitative polymerase chain reaction (ARMS-qPCR) and droplet digital polymerase chain reaction (ddPCR) approaches in the detection of EGFR mutation and explore the feasibility of using ddPCR in the detection of samples with low mutation rates. EGFR gene mutations in plasmid samples with different T790M mutation rates (0.1–5%) and 10 clinical samples were detected using the ARMS-qPCR and ddPCR approaches. The results demonstrated that the ARMS-qPCR method stably detected the plasmid samples (6,000 copies) with 5 and 1% mutation rates, while the ddPCR approach reliably detected those with 5% (398 copies), 1% (57 copies), 0.5% (24 copies) and 0.1% (average 6 copies) mutation rates. For the 10 clinical samples, the results for nine samples by the ARMS-qPCR and ddPCR methods were consistent; however, the sample N006, indicated to be EGFR wild-type by ARMS-qPCR, was revealed to have a clear EGFR T790M mutation with seven copies of mutant alleles in a background of 6,000 wild-type copies using ddPCR technology. This study demonstrates the feasibility of applying the ddPCR system to detect EGFR mutation and identified the advantage of ddPCR in the detection of samples with a low EGFR mutation abundance, particularly the secondary EGFR T790M resistance mutation, which enables early diagnosis before acquired resistance to tyrosine kinase inhibitors becomes clinically detectable. PMID:25780439

ZHANG, BO; XU, CHUN-WEI; SHAO, YUN; WANG, HUAI-TAO; WU, YONG-FANG; SONG, YE-YING; LI, XIAO-BING; ZHANG, ZHE; WANG, WEN-JING; LI, LI-QIONG; CAI, CONG-LI

2015-01-01

324

Recurrent Deep Intronic Mutations in the SLC12A3 Gene Responsible for Gitelman's Syndrome  

PubMed Central

Summary Background and objectives Gitelman's syndrome (GS) is an autosomal recessive renal tubular disorder caused by mutations in the SLC12A3 gene encoding the thiazide-sensitive Na+-Cl? cotransporter (NCC). Despite meticulous sequencing of genomic DNA, approximately one-third of GS patients are negative or heterozygotes for the known mutations. Design, Setting, Participants, & Measurements Because blood leukocytes express NCC mRNA, we evaluate whether deep intronic mutations contribute to GS patients with uniallelic or undetectable SLC12A3 mutations. Twenty-nine patients with GS (men/women = 16/13), including eight negative and 21 uniallelic SLC12A3 mutations from 19 unrelated families, and normal controls were enrolled in an academic medical center. Analysis of cDNA from blood leukocytes, sequencing of the corresponding introns of genomic DNA for abnormal transcript, and analysis of NCC protein expression from renal biopsy were performed. Results We identified nine Taiwan aboriginal patients carrying c.1670–191C?T mutations in intron 13 and 10 nonaboriginal patients carrying c.2548+253C?T mutations in intron 21 from 14 families (14/19). These two mutations undetected in 100 healthy subjects created pseudoexons containing new premature termination codons. Haplotype analysis with markers flanking SLC12A3 revealed that both mutations did not have founder effects. Apical NCC expression in the DCT of renal tissue was markedly diminished in two patients carrying deep intronic mutations. Conclusions Deep intronic mutations in SLC12A3 causing defective NCC expression can be identified with the RNA-based approach in patients with GS. c.1670–191C?T and c.2548+253C?T are hot spot mutations that can be screened in GS patients with uniallelic or negative SLC12A3 mutations. PMID:21051746

Lo, Yi-Fen; Nozu, Kandai; Iijima, Kazumoto; Morishita, Takahiro; Huang, Che-Chung; Yang, Sung-Sen; Sytwu, Huey-Kang; Fang, Yu-Wei; Tseng, Min-Hua

2011-01-01

325

Biased gene conversion, copy number, and apparent mutation rate differences within chloroplast and bacterial genomes.  

PubMed

We investigate the possibility that differences between synonymous substitution rates of organelle and bacterial genes differing only in copy number may be due to conversion bias. We find that the rather large observed difference in the synonymous rates between genes in the single copy and inverted-repeat regions of chloroplasts can be accounted for by a very small bias against new mutants. More generally, differences in the within-organelle fixation probability result in different apparent mutation rates as measured by the expected rate of appearance of cells homoplasmic for new mutants. Thus, differences in intracellular population parameters rather than molecular mechanisms can account for some variation in the apparent mutation rates of organelle genes, and possibly in other systems with variable numbers of gene copies. On the other hand, our analysis suggests that conversion bias is not a likely explanation for relatively low mutation rates observed near the replication origin of bacterial chromosomes. PMID:1551584

Birky, C W; Walsh, J B

1992-03-01

326

De novo gene mutations highlight patterns of genetic and neural complexity in schizophrenia.  

PubMed

To evaluate evidence for de novo etiologies in schizophrenia, we sequenced at high coverage the exomes of families recruited from two populations with distinct demographic structures and history. We sequenced a total of 795 exomes from 231 parent-proband trios enriched for sporadic schizophrenia cases, as well as 34 unaffected trios. We observed in cases an excess of de novo nonsynonymous single-nucleotide variants as well as a higher prevalence of gene-disruptive de novo mutations relative to controls. We found four genes (LAMA2, DPYD, TRRAP and VPS39) affected by recurrent de novo events within or across the two populations, which is unlikely to have occurred by chance. We show that de novo mutations affect genes with diverse functions and developmental profiles, but we also find a substantial contribution of mutations in genes with higher expression in early fetal life. Our results help define the genomic and neural architecture of schizophrenia. PMID:23042115

Xu, Bin; Ionita-Laza, Iuliana; Roos, J Louw; Boone, Braden; Woodrick, Scarlet; Sun, Yan; Levy, Shawn; Gogos, Joseph A; Karayiorgou, Maria

2012-12-01

327

Cap myopathy caused by a mutation of the skeletal alpha-actin gene ACTA1.  

PubMed

Cap myopathy is a congenital myopathy with cap-like structures under the sarcolemma. Mutations in TPM2 and TPM3 genes have been reported in cap myopathy so far. We report a newborn boy with persistent profound weakness who required gastro-jejunal tube feeding, tracheostomy and life-long ventilation until he died at 5 years of age. Muscle biopsy at 5 weeks of age was uninformative. Repeat biopsy at 4.5 years revealed subsarcolemmally located caps that were immunopositive for alpha-actinin, actin and to some extent, desmin. EM confirmed loosely arranged thin filaments and paucity of thick filaments. Molecular analysis of ACTA1 gene identified a novel de novo Met49Val [corrected] mutation. In addition to a new ACTA1 gene mutation, our case emphasizes the genetic heterogeneity of cap myopathy and its association with ACTA1 gene as well as the importance of repeat muscle biopsy in patients with undiagnosed muscle weakness. PMID:20303757

Hung, Ryan M; Yoon, Grace; Hawkins, Cynthia E; Halliday, Willliam; Biggar, Doug; Vajsar, Jiri

2010-04-01

328

The discovery that mutations in single genes can modulate aging was not only fascinating but it provided  

E-print Network

The discovery that mutations in single genes can modulate aging was not only in 68 genes have been shown to affect lifespan in mice. Among mouse genes in which mutations extend-releasing factor for Ras, exhibit a significant increase (~20%) in average and maximum lifespan. This increase

de Magalhăes, Joăo Pedro

329

Association of MTHFR gene C677T mutation with diabetic peripheral neuropathy and diabetic retinopathy  

PubMed Central

Purpose Diabetic peripheral neuropathy (DPN) is one of the most common diabetic chronic complications. Methylenetetrahydrofolate reductase (MTHFR) gene variants have been associated with vasculopathy that has been linked to diabetic neuropathy. The aim of the present study was to investigate the possible association between MTHFR gene C677T mutation and DPN and evaluate if there is an association with clinical features in a relatively large cohort of Turkish patients. Methods The study included 230 patients affected by DPN and 282 healthy controls. Genomic DNA was isolated and genotyped using the polymerase chain reaction–based restriction fragment length polymorphism assay for the MTHFR gene C677T mutation. Results The genotype and allele frequencies of the C677T mutation showed statistically significant differences between the patients with DPN and the controls (p=0.003 and p=0.002, respectively). After the patients with DPN were stratified according to clinical and demographic characteristics, a significant association was observed between the C677T mutation and history of retinopathy (p=0.039). Conclusions A high association between the MTHFR gene C677T mutation and DPN was observed in the present study. In addition, history of retinopathy was associated with the MTHFR C677T mutation in patients with DPN. PMID:23901246

Yigit, Serbulent; Inanir, Ahmet

2013-01-01

330

Mutations in the ATP13A2 Gene and Parkinsonism: A Preliminary Review  

PubMed Central

Parkinson's disease (PD) is a major neurodegenerative disorder for which the etiology and pathogenesis remain as elusive as for Alzheimer's disease. PD appears to be caused by genetic and environmental factors, and pedigree and cohort studies have identified numerous susceptibility genes and loci related to PD. Autosomal recessive mutations in the genes Parkin, Pink1, DJ-1, ATP13A2, PLA2G6, and FBXO7 have been linked to PD susceptibility. Such mutations in ATP13A2, also named PARK9, were first identified in 2006 in a Chilean family and are associated with a juvenile-onset, levodopa-responsive type of Parkinsonism called Kufor-Rakeb syndrome (KRS). KRS involves pyramidal degeneration, supranuclear palsy, and cognitive impairment. Here we review current knowledge about the ATP13A2 gene, clinical characteristics of patients with PD-associated ATP13A2 mutations, and models of how the ATP13A2 protein may help prevent neurodegeneration by inhibiting ?-synuclein aggregation and supporting normal lysosomal and mitochondrial function. We also discuss another ATP13A2 mutation that is associated with the family of neurodegenerative disorders called neuronal ceroid lipofuscinoses (NCLs), and we propose a single pathway whereby ATP13A2 mutations may contribute to NCLs and Parkinsonism. Finally, we highlight how studies of mutations in this gene may provide new insights into PD pathogenesis and identify potential therapeutic targets. PMID:25197640

Yang, Xinglong; Xu, Yanming

2014-01-01

331

Improved Hematopoietic Differentiation Efficiency of Gene-Corrected Beta-Thalassemia Induced Pluripotent Stem Cells by CRISPR/Cas9 System.  

PubMed

The generation of beta-thalassemia (?-Thal) patient-specific induced pluripotent stem cells (iPSCs), subsequent homologous recombination-based gene correction of disease-causing mutations/deletions in the ?-globin gene (HBB), and their derived hematopoietic stem cell (HSC) transplantation offers an ideal therapeutic solution for treating this disease. However, the hematopoietic differentiation efficiency of gene-corrected ?-Thal iPSCs has not been well evaluated in the previous studies. In this study, we used the latest gene-editing tool, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9), to correct ?-Thal iPSCs; gene-corrected cells exhibit normal karyotypes and full pluripotency as human embryonic stem cells (hESCs) showed no off-targeting effects. Then, we evaluated the differentiation efficiency of the gene-corrected ?-Thal iPSCs. We found that during hematopoietic differentiation, gene-corrected ?-Thal iPSCs showed an increased embryoid body ratio and various hematopoietic progenitor cell percentages. More importantly, the gene-corrected ?-Thal iPSC lines restored HBB expression and reduced reactive oxygen species production compared with the uncorrected group. Our study suggested that hematopoietic differentiation efficiency of ?-Thal iPSCs was greatly improved once corrected by the CRISPR/Cas9 system, and the information gained from our study would greatly promote the clinical application of ?-Thal iPSC-derived HSCs in transplantation. PMID:25517294

Song, Bing; Fan, Yong; He, Wenyin; Zhu, Detu; Niu, Xiaohua; Wang, Ding; Ou, Zhanhui; Luo, Min; Sun, Xiaofang

2015-05-01

332

MECP2 and CDKL5 gene mutation analysis in Chinese patients with Rett syndrome.  

PubMed

Rett syndrome (RTT) is a progressive neurodevelopmental disorder that is caused by mutations in the X-linked methyl-CpG-binding protein2 (MECP2) gene. In this study, the MECP2 sequences in 121 unrelated Chinese patients with classical or atypical RTT were screened for deletions and mutations. In all, we identified 45 different MECP2 mutations in 102 of these RTT patients. The p. T158M mutation (15.7%) was the most common, followed in order of frequency by p. R168X (11.8%), p. R133C (6.9%), p. R270X (6.9%), p. G269fs (6.9%), p. R255X (4.9%), and p. R306C (3.9%). In addition, we identified five novel MECP2 mutations: three missense (p. K305E, p. V122M, p. A358T), one insertion (c.45-46insGGAGGA), and one 22 bp deletion (c.881-902del22). Large deletions represented 10.5% of all identified MECP2 mutations. Conversely, mutations in exon 1 appeared to be rare (0.9%). The remaining cases without MECP2 mutations were screened for the cyclin-dependent kinase-like 5 (CDKL5) gene using denaturing high-performance liquid chromatography (DHPLC). One synonymous mutation (p. I72I) was found in exon 5, suggesting that CDKL5 is a rare cause of RTT. The overall MECP2 mutation detection rate for this patient series was 84.3:87.9% in 107 classical RTT cases and 57.1% in 14 atypical RTT cases. Moreover, there were two patients with homozygous mutations and normal female karyotypes. However, we did not pinpoint a significant relationship between genotype and phenotype in these cases. PMID:17089071

Li, Mei-Rong; Pan, Hong; Bao, Xin-Hua; Zhang, Yu-Zhi; Wu, Xi-Ru

2007-01-01

333

A de-novo STXBP1 gene mutation in a patient showing the Rett syndrome phenotype.  

PubMed

This study reports on a 9-year-old girl who developed West syndrome and showed clinical features fulfilling the main revised diagnostic criteria for typical Rett syndrome (hand washing, severe cognitive impairment with absence of language, ataxic gait, progressive scoliosis and autistic features). Mutation analyses for methyl-CpG-binding protein 2 (MECP2), cyclin-dependent kinase-like 5 (CDKL5/STK9), ARX and Forkhead box G1 (FOXG1) genes were carried out, with negative results. A known de-novo c.1217G>A missense mutation in exon 14 leading to the substitution of a conserved residue, p.R406H in domain3b of the syntaxin-binding protein 1 (STXBP1) gene, was detected. The STXBP1 gene encodes the syntaxin-binding protein 1, a neuron-specific protein involved in synaptic vesicle release at both glutaminergic and GABAergic synapses. This function is also affected by MECP2 gene mutations, which are known to lead to a decrease in glutamate and GABA receptors' density. It is possible to speculate that the impairment in synaptic plasticity represents the pathogenic link between MECP2 and STXBP1 gene mutations. On reviewing the clinical features of the reported patients with the same mutation in the STXBP1 gene, it has been observed that poor eye contact, tremour, dyskinesia, head/hand stereotypies and both cognitive and motor progressive deterioration are common symptoms, although never considered as indicative of a Rett syndrome phenotype. In conclusion, the case described here suggests a relationship between the Rett syndrome and the STXBP1 gene not described so far, making the search for STXBP1 gene mutations advisable in patients with Rett syndrome and early onset of epilepsy. PMID:25714420

Romaniello, Romina; Saettini, Francesco; Panzeri, Elena; Arrigoni, Filippo; Bassi, Maria T; Borgatti, Renato

2015-03-25

334

Mutation analysis of the HDAC 1, 2, 8 and CDKL5 genes in Rett syndrome patients without mutations in MECP2.  

PubMed

Mutations in the MECP2 gene are found in only 80% of patients with Rett syndrome (RTT). Therefore other genes have to be involved in the pathogenesis of RTT. By using our defined diagnostic criteria we first re-evaluated 50 girls with possible RTT in whom the sequencing of the MECP2 gene had not revealed any mutations. Only 15 of theses patients fulfilled all criteria for RTT and could be considered to have classical RTT. In eight of these, further molecular analyses revealed large deletions of the MECP2 gene. In the remaining seven girls we then analyzed the genes HDAC1, HDAC2, and HDAC8 that encode for the histone deacetylases 1, 2, and 8 which interact with MeCP2 and are essential for its function. Although these histone deacetylase genes have been considered as good candidate genes for RTT our molecular analysis of these genes did not detect any mutations. Because recently mutations in CDKL5 were reported in patients with RTT, we included this gene in our analysis but failed to detect any mutations. We conclude that only a subgroup of girls with possible RTT and no detectable mutation in the sequencing of the MECP2 gene do really have classical RTT. In many of those large MECP2 gene deletions can be detected by further analysis. The genes HDAC1, HDAC2, and HDAC8 do not seem to play a role in the pathogenesis of RTT and at least in our subgroup no mutations in the CDKL5 gene were detected. PMID:16086395

Huppke, Peter; Ohlenbusch, Andreas; Brendel, Cornelia; Laccone, Franco; Gärtner, Jutta

2005-08-30

335

Mutations in the helix termination motif of mouse type I IRS keratin genes impair the assembly of keratin intermediate filament  

Microsoft Academic Search

Two classical mouse hair coat mutations, Rex (Re) and Rex wavy coat (Rewc), are linked to the type I inner root sheath (IRS) keratin genes of chromosome 11. An N-ethyl-N-nitrosourea-induced mutation, M100573, also maps close to the type I IRS keratin genes. In this study, we demonstrate that Re and M100573 mice bear mutations in the type I IRS gene

Shigekazu Tanaka; Ikuo Miura; Atsushi Yoshiki; Yoriko Kato; Haruka Yokoyama; Akiko Shinogi; Hiroshi Masuya; Shigeharu Wakana; Masaru Tamura; Toshihiko Shiroishi

2007-01-01

336

Identification of two poorly prognosed ovarian carcinoma subtypes associated with CHEK2 germ-line mutation and non-CHEK2 somatic mutation gene signatures.  

PubMed

High-grade serous ovarian cancer (HG-SOC), a major histologic type of epithelial ovarian cancer (EOC), is a poorly-characterized, heterogeneous and lethal disease where somatic mutations of TP53 are common and inherited loss-of-function mutations in BRCA1/2 predispose to cancer in 9.5-13% of EOC patients. However, the overall burden of disease due to either inherited or sporadic mutations is not known. We performed bioinformatics analyses of mutational and clinical data of 334 HG-SOC tumor samples from The Cancer Genome Atlas to identify novel tumor-driving mutations, survival-significant patient subgroups and tumor subtypes potentially driven by either hereditary or sporadic factors. We identified a sub-cluster of high-frequency mutations in 22 patients and 58 genes associated with DNA damage repair, apoptosis and cell cycle. Mutations of CHEK2, observed with the highest intensity, were associated with poor therapy response and overall survival (OS) of these patients (P = 8.00e-05), possibly due to detrimental effect of mutations at the nuclear localization signal. A 21-gene mutational prognostic signature significantly stratifies patients into relatively low or high-risk subgroups with 5-y OS of 37% or 6%, respectively (P = 7.31e-08). Further analysis of these genes and high-risk subgroup revealed 2 distinct classes of tumors characterized by either germline mutations of genes such as CHEK2, RPS6KA2 and MLL4, or somatic mutations of other genes in the signature. Our results could provide improvement in prediction and clinical management of HG-SOC, facilitate our understanding of this complex disease, guide the design of targeted therapeutics and improve screening efforts to identify women at high-risk of hereditary ovarian cancers distinct from those associated with BRCA1/2 mutations. PMID:24879340

Ow, Ghim Siong; Ivshina, Anna V; Fuentes, Gloria; Kuznetsov, Vladimir A

2014-07-15

337

Mutations in the cationic trypsinogen gene and evidence for genetic heterogeneity in hereditary pancreatitis  

PubMed Central

Hereditary pancreatitis (HP) is a rare inherited disorder, characterised by recurrent episodes of pancreatitis often beginning in early childhood. The mode of inheritance suggests an autosomal dominant trait with incomplete penetrance. The gene, or at least one of the genes, responsible for hereditary pancreatitis has been mapped to the long arm of chromosome 7 and a missense mutation, an arginine to histidine substitution at residue 117 in the trypsinogen cationic gene (try4) has been shown to segregate with the HP phenotype. The aim of this work was to investigate the molecular basis of hereditary pancreatitis. This study was performed on 14 HP families. The five exons of the trypsinogen cationic gene were studied using a specific gene amplification assay combined with denaturing gradient gel electrophoresis (DGGE). The present paper describes three novel mutations, namely K23R and N29I and a deletion -28delTCC in the promoter region. We also found a polymorphism in exon 4, D162D. In eight of these families we found a mutation which segregates with the disease. A segregation analysis using microsatellite markers carried out on the other families suggests genetic heterogeneity in at least one of them. Our findings confirm the implication of the cationic trypsinogen gene in HP and highlight allelic diversity associated with this phenotype. We also show that the pattern of inheritance of HP is probably complex and that other genes may be involved in this genetic disease.???Keywords: hereditary pancreatitis; mutation analysis; cationic trypsinogen PMID:10204851

Ferec, C; Raguenes, O; Salomon, R; Roche, C; Bernard, J; Guillot, M; Quere, I; Faure, C; Mercier, B; Audrezet, M; Guillausseau, P; Dupont, C; Munnich, A; Bignon, J; Le Bodic, L

1999-01-01

338

Congenital Heart Defects Are Rarely Caused by Mutations in Cardiac and Smooth Muscle Actin Genes  

PubMed Central

Background. Congenital heart defects (CHDs) often have genetic background due to missense mutations in cardiomyocyte-specific genes. For example, cardiac actin was shown to be involved in pathogenesis of cardiac septum defects and smooth muscle actin in pathogenesis of aortic aneurysm in combination with patent ductus arteriosus (PDA). In the present study, we further searched for mutations in human ?-cardiac actin (ACTC1) and smooth muscle ?-actin (ACTA2) genes as a possible cause of atrial septum defect type II (ASDII) and PDA. Findings. Total genomic DNA was extracted from peripheral blood of 86 individuals with ASDs and 100 individuals with PDA. Coding exons and flanking intron regions of ACTC1 (NM_005159.4) and ACTA2 (NM_001613) were amplified by PCR with specific primers designed according to the corresponding gene reference sequences. PCR fragments were directly sequenced and analyzed. Sequence analysis of ACTC1 and ACTA2 did not identify any nucleotide changes that altered the coding sense of the genes. In ACTC1 gene, we were able to detect one previously described nucleotide polymorphism (rs2307493) resulting in a synonymous substitution. The frequency of this SNP was similar in the study and control group, thus excluding it from the possible disease-associated variants. Conclusions. Our results confirmed that the mutations in ACTC1 gene are rare (at least <1%) cause of ASDII. Mutations in ACTA2 gene were not detected in patients with PDA, thus being excluded from the list of frequent PDA-associated genetic defects.

Khodyuchenko, Tatiana; Zlotina, Anna; Pervunina, Tatiana; Zverev, Dmitry; Malashicheva, Anna; Kostareva, Anna

2015-01-01

339

The Nature and Extent of Mutational Pleiotropy in Gene Expression of Male Drosophila serrata  

PubMed Central

The nature and extent of mutational pleiotropy remain largely unknown, despite the central role that pleiotropy plays in many areas of biology, including human disease, agricultural production, and evolution. Here, we investigate the variation in 11,604 gene expression traits among 41 mutation accumulation (MA) lines of Drosophila serrata. We first confirmed that these expression phenotypes were heritable, detecting genetic variation in 96% of them in an outbred, natural population of D. serrata. Among the MA lines, 3385 (29%) of expression traits were variable, with a mean mutational heritability of 0.0005. In most traits, variation was generated by mutations of relatively small phenotypic effect; putative mutations with effects of greater than one phenotypic standard deviation were observed for only 8% of traits. With most (71%) traits unaffected by any mutation, our data provide no support for universal pleiotropy. We further characterized mutational pleiotropy in the 3385 variable traits, using sets of 5, randomly assigned, traits. Covariance among traits chosen at random with respect to their biological function is expected only if pleiotropy is extensive. Taking an analytical approach in which the variance unique to each trait in the random 5-trait sets was partitioned from variance shared among traits, we detected significant (at 5% false discovery rate) mutational covariance in 21% of sets. This frequency of statistically supported covariance implied that at least some mutations must pleiotropically affect a substantial number of traits (>70; 0.6% of all measured traits). PMID:24402375

McGuigan, Katrina; Collet, Julie M.; McGraw, Elizabeth A.; Ye, Yixin H.; Allen, Scott L.; Chenoweth, Stephen F.; Blows, Mark W.

2014-01-01

340

Mutational and expressional analysis of ERBB3 gene in common solid cancers.  

PubMed

ERBB3 is a member of EGFR family receptor tyrosine kinases, genetic alterations of which are common and therapeutically targeted in human cancers. Recently, somatic mutations of ERBB3 gene, including recurrent mutation in exon 3 altering Val104, were reported in gastric cancers (GC) and colorectal cancers (CRC), strongly suggesting its role in the development of GC and CRC. To examine whether the recurrent ERBB3 mutations of exon 3 occur in GC and CRC, and other malignancies as well, we analyzed the ERBB3 in 1677 cancer tissues by a single-strand conformation polymorphism (SSCP) assay. We identified ERBB3 mutations altering the Val104 mutations in GC (0.5%) and CRC (2.2%). However, we did not find the ERBB3 mutations in the other cancers besides GC and CRC. We observed that an increased intensity of phosphorylated ERBB3 (pERBB3) in GC and CRC. Of note, all of the cancers with ERBB3 mutations displayed an increased intensity of pERBB3 immunostaining. Our data indicate that the recurrent ERBB3 mutations altering Val104 occur predominantly in GC and CRC. Also, the data suggest that ERBB3 is altered in GC and CRC by various ways, including somatic mutations and increased expression that might play roles in tumorigenesis. PMID:24909266

Choi, Mi Ryoung; An, Chang Hyeok; Chung, Yeun Jun; Choi, Youn Jin; Yoo, Nam Jin; Lee, Sug Hyung

2014-12-01

341

Mutation Spectrum of Six Genes in Chinese Phenylketonuria Patients Obtained through Next-Generation Sequencing  

PubMed Central

Background The identification of gene variants plays an important role in the diagnosis of genetic diseases. Methodology/Principal Findings To develop a rapid method for the diagnosis of phenylketonuria (PKU) and tetrahydrobiopterin (BH4) deficiency, we designed a multiplex, PCR-based primer panel to amplify all the exons and flanking regions (50 bp average) of six PKU-associated genes (PAH, PTS, GCH1, QDPR, PCBD1 and GFRP). The Ion Torrent Personal Genome Machine (PGM) System was used to detect mutations in all the exons of these six genes. We tested 93 DNA samples from blood specimens from 35 patients and their parents (32 families) and 26 healthy adults. Using strict bioinformatic criteria, this sequencing data provided, on average, 99.14% coverage of the 39 exons at more than 70-fold mean depth of coverage. We found 23 previously documented variants in the PAH gene and six novel mutations in the PAH and PTS genes. A detailed analysis of the mutation spectrum of these patients is described in this study. Conclusions/Significance These results were confirmed by Sanger sequencing. In conclusion, benchtop next-generation sequencing technology can be used to detect mutations in monogenic diseases and can detect both point mutations and indels with high sensitivity, fidelity and throughput at a lower cost than conventional methods in clinical applications. PMID:24705691

Cen, Zhong; Yu, Li; Lin, Lin; Hao, Jing; Yang, Zhigang; Peng, Jiabao; Cui, Shujian; Huang, Jian

2014-01-01

342

Common Mediterranean Fever (MEFV) Gene Mutations Associated with Ankylosing Spondylitis in Turkish Population  

PubMed Central

Ankylosing spondylitis (AS) is a common inflammatory rheumatic disease. Mediterranean fever (MEFV) gene, which has already been identified as being responsible for familial Mediterranean fever (FMF), is also a suspicious gene for AS because of the clinical association of these two diseases. The aim of this study was to explore the frequency and clinical significance of MEFV gene mutations (M694V, M680I, V726A, E148Q and P369S) in a cohort of Turkish patients with AS. Genomic DNAs of 103 AS patients and 120 controls were isolated and genotyped using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods. There was a statistically significant difference of the MEFV gene mutation carrier rates between AS patients and healthy controls (p = 0.004, OR: 2.5, 95% CI: 1.32–4.76). This association was also observed in allele frequencies (p = 0.005, OR: 2.3, 95% CI: 1.27–4.2). A relatively higher frequency was observed for M694V mutation in AS patients than controls (10.7% versus 4.2% , p = 0.060). There were no significant differences between MEFV mutation carriers and non-carriers with respect to the clinical and demographic characteristics. The results of this study suggest that MEFV gene mutations are positively associated with a predisposition to develop AS. PMID:22960328

Yigit, Serbulent; Inanir, Ahmet; Karakus, Nevin; Kesici, Esra; Bozkurt, Nihan

2012-01-01

343

GeneChip{sup {trademark}} screening assay for cystic fibrosis mutations  

SciTech Connect

GeneChip{sup {trademark}} assays are based on high density, carefully designed arrays of short oligonucleotide probes (13-16 bases) built directly on derivatized silica substrates. DNA target sequence analysis is achieved by hybridizing fluorescently labeled amplification products to these arrays. Fluorescent hybridization signals located within the probe array are translated into target sequence information using the known probe sequence at each array feature. The mutation screening assay for cystic fibrosis includes sets of oligonucleotide probes designed to detect numerous different mutations that have been described in 14 exons and one intron of the CFTR gene. Each mutation site is addressed by a sub-array of at least 40 probe sequences, half designed to detect the wild type gene sequence and half designed to detect the reported mutant sequence. Hybridization with homozygous mutant, homozygous wild type or heterozygous targets results in distinctive hybridization patterns within a sub-array, permitting specific discrimination of each mutation. The GeneChip probe arrays are very small (approximately 1 cm{sup 2}). There miniature size coupled with their high information content make GeneChip probe arrays a useful and practical means for providing CF mutation analysis in a clinical setting.

Cronn, M.T.; Miyada, C.G.; Fucini, R.V. [Affymetrix, Santa Clara, CA (United States)] [and others

1994-09-01

344

Mutations that alter the timing and pattern of cubitus interruptus gene expression in Drosophila melanogaster  

SciTech Connect

The cubitus interruptus (ci) gene is a member of the Drosophila segment polarity gene family and encodes a protein with a zinc finger domain homologous to the vertebrate Gli genes and the nematode tra-1 gene. Three classes of existing mutations in the ci locus alter the regulation of ci expression and can be used to examine ci function during development. The first class of ci mutations causes interruptions in wing veins four and five due to inappropriate expression of the ci product in the posterior compartment of imaginal discs. The second class of mutations eliminates ci protein early in embryogenesis and causes the deletion of structures that are derived from the region including and adjacent to the engrailed expressing cells. The third class of mutations eliminates ci protein later in embryogenesis and blocks the formation of the ventral naked cuticle. The loss of ci expression at these two different stages in embryonic development correlates with the subsequent elimination of wingless expression. Adults heterozygous for the unique ci{sup Ce} mutation have deletions between wing veins three and four. A similar wing defect is present in animals mutant for the segment polarity gene fused that encodes a putative serine/threonine kinase. In ci{sup Ce}/+ and fused mutants, the deletions between wing veins three and four correlate with increased ci protein levels in the anterior compartment. Thus, proper regulation of both the ci mRNA and protein appears to be critical for normal Drosophila development. 47 refs., 9 figs., 1 tab.

Slusarski, D.C.; Motzny, C.K.; Holmgren, R. [Northwestern Univ., Evanston, IL (United States)

1995-01-01

345

Clonal analysis of colorectal tumors using K-ras and p53 gene mutations as markers.  

PubMed

Mutations to the K-ras oncogene and p53 tumor suppressor gene are two of the most common genetic lesions in human cancers. In the present study we examined the clonality of colorectal tumors with respect to each of these genetic alterations. Screening for mutations was carried out using the polymerase chain reaction-based technique of single-strand conformation polymorphism. Eleven primary colorectal adenocarcinomas and two secondary adenocarcinomas were analyzed at four different sites within the tumor. Involved pericolic lymph nodes were collected from nine of these cases, a metastatic deposit in the liver was obtained in one case, and adjacent adenomatous lesions were collected in two cases. Seven tumors contained mutations in either the K-ras or p53 genes. In all cases, DNA derived from multiple sites within an individual tumor or metastatic deposits arising from that tumor showed the same pattern of gene mutation. Immunohistochemical staining for p53 protein overexpression also showed similar patterns of reactivity within individual tumors and their metastatic deposits. These results suggest that the major clonal expansion of colorectal carcinomas occurs after the acquisition of mutations in these genes. Our results also indicate that sampling errors are unlikely to occur in molecular studies aimed at defining the role of these genes in colorectal cancer progression. PMID:8634782

Dix, B R; Robbins, P D; Spagnolo, D V; Padovan, G L; House, A K; Iacopetta, B J

1995-12-01

346

A mutation in a dog gene opens new research into the defensin protein  

NSDL National Science Digital Library

Researchers who were trying to find the mutated gene that controls coat color in dogs now report that they found the gene, and have also discovered that it has an unexpected additional role. The gene also sends a signal to a member of a protein family that is responsible for defending the body against infection. The proteins are called defensins, because their job is to defend the body.

American Association for the Advancement of Science (AAAS; )

2007-10-18

347

The spectrum of MEFV gene mutations and genotypes in Van province, the eastern region of Turkey, and report of a novel mutation (R361T).  

PubMed

Familial Mediterranean fever (FMF) is the most common hereditary inflammatory periodic disease, characterized by recurrent episodes of fever and abdominal pain, synovitis, and pleuritis. The aim of this study was to determine the frequency and distribution of Mediterranean fever (MEFV) gene mutations in Van province of Eastern Anatolia and to compare them with the other studies from various regions of Turkey. Therefore, we retrospectively evaluated MEFV gene mutations in 1058 pediatric patients with suspected FMF. The MEFV gene mutations were investigated using Sanger sequencing and the multiplex minisequencing technique. We identified 37 different genotypes and 16 different mutations. The four most common mutations and allelic frequencies were M694V (36.50%), E148Q (32.77%), V726A (14.09%), and M694I (4.41%). M694V was the most common mutation, and the M694I frequency was found to be higher compared to studies from other regions of Turkey. In addition, we identified a novel missense mutation (R361T, c.1082G>C) in exon 3 of the MEFV gene in a 12-year-old boy, who had a typical FMF phenotype. In conclusion, this study evaluated the distribution of MEFV gene mutations in children with FMF as the first study conducted in Van province, Eastern Anatolia. PMID:25703702

Co?kun, Salih; Ustyol, Lokman; Bayram, Yasemin; Selçuk Bekta?, M; Gulsen, Suleyman; Çim, Abdullah; Uluca, Unal; Sava?, Didem

2015-05-10

348

Mutational analysis of the VCP gene in Parkinson’s Disease  

PubMed Central

Mutations in the valosin-containing protein gene (VCP) have been identified in neurological disorders (IBMPFD and ALS) and are thought to play a role in the clearance of abnormally folded proteins. Parkinsonism has been noted in kindreds with VCP mutations. Based on this, we hypothesized that mutations in VCP may also contribute to idiopathic PD. We screened the coding region of the VCP gene in a large cohort of 768 late onset PD cases (average age at onset = 70 years), both sporadic and with positive family history. We identified a number of rare single nucleotide changes, including a variant previously described to be pathogenic, but no clear disease-causing variants. We conclude that mutations in VCP are not a common cause for idiopathic PD. PMID:21920633

Majounie, Elisa; Traynor, Bryan J.; Chiň, Adriano; Restagno, Gabriella; Mandrioli, Jessica; Benatar, Michael; Taylor, J. Paul; Singleton, Andrew B.

2011-01-01

349

A Nonsense Mutation in the Acid ?-Glucosidase Gene Causes Pompe Disease in Finnish and Swedish Lapphunds  

PubMed Central

Pompe disease is a recessively inherited and often fatal disorder caused by the deficiency of acid ?-glucosidase, an enzyme encoded by the GAA gene and needed to break down glycogen in lysosomes. This glycogen storage disease type II has been reported also in Swedish Lapphund dogs. Here we describe the genetic defect in canine Pompe disease and show that three related breeds from Scandinavia carry the same mutation. The affected dogs are homozygous for the GAA c.2237G>A mutation leading to a premature stop codon at amino acid position 746. The corresponding mutation has previously been reported in humans and causes infantile Pompe disease in combination with a second fully deleterious mutation. The affected dogs from both the Finnish as well as the Swedish breed mimic infantile-onset Pompe disease genetically, but also clinico-pathologically. Therefore this canine model provides a valuable tool for preclinical studies aimed at the development of gene therapy in Pompe disease. PMID:23457621

Seppälä, Eija H.; Reuser, Arnold J. J.; Lohi, Hannes

2013-01-01

350

Identification of a nonsense mutation in the PAX9 gene in molar oligodontia.  

PubMed

Development of dentition is controlled by numerous genes, as has been shown by experimental animal studies and mutations that have been identified by genetic studies in man. Here we report a nonsense mutation in the PAX9 gene that is associated with molar tooth agenesis in a Finnish family. The A340T transversion creates a stop codon at lysine 114, and truncates the coded PAX9 protein at the end of the DNA-binding paired-box. All the affected members of the family were heterozygous for the mutation. The tooth agenesis phenotype involves all permanent second and third molars and most of the first molars and resembles the earlier reported phenotype that was also associated with a PAX9 mutation. The phenotype is presumably a consequence of haploinsufficiency of PAX9. In another Finnish family with molar tooth agenesis, we could not find similar sequence changes in PAX9. PMID:11781684

Nieminen, P; Arte, S; Tanner, D; Paulin, L; Alaluusua, S; Thesleff, I; Pirinen, S

2001-10-01

351

The stop mutation R553X in the CFTR gene results in exon skipping  

SciTech Connect

Stop or nonsense mutations are known to disrupt gene function in a number of different ways. The authors have studied the effects of the stop mutation R553X in exon 11 of the CFTR gene by analyzing mRNA extracted from nasal epithelial cells harvested from patients with cystic fibrosis. Four patients who were compound heterozygotes for the R553X mutation were studied. Ten non-CF control subjects were also studied. In all four patients, full-length CFTR mRNA was identified, but only a very small proportion of this was derived from the R553X allele. A smaller transcript, lacking exon 11, was also seen in the R553X patients but not in the controls. Most of this transcript was derived from the R553X allele. These results suggest that the R553X mutation results in skipping of the exon in which it is located. 14 refs., 3 figs.

Hull, J.; Shackleton, S.; Harris, A. (Institute of Molecular Medicine, Oxford (United Kingdom))

1994-01-15

352

A novel nonsense mutation of the KAL1 gene (p.Trp204*) in Kallmann syndrome  

PubMed Central

Objective To describe a novel KAL1 mutation in patients affected by Kallmann syndrome. Setting Endocrinology Clinic of the Joăo de Barros Barreto University Hospital – Federal University of Pará, Brazil. Methods Clinical examination, hormone assays and sequencing of exons 5, 6 and 9 of the KAL1 gene in four Brazilian brothers with Kallmann syndrome. Results Detected a novel KAL1 mutation, c.612G.A/p.Trp204*, in four hemizygous brothers with Kallmann syndrome, and five heterozygous female family members. Conclusion The novel p.Trp204* mutation of the KAL1 gene results in the production of a truncated anosmin-1 enzyme in patients with Kallmann syndrome. This finding broadens the spectrum of pathogenic mutations for this disease. PMID:25328414

El Husny, Antonette Souto; Raiol-Moraes, Milene; Fernandes-Caldato, Milena Coelho; Ribeiro-dos-Santos, Ândrea

2014-01-01

353

The interplay of mutations and electronic properties in disease-related genes  

NASA Astrophysics Data System (ADS)

Electronic properties of DNA are believed to play a crucial role in many phenomena in living organisms, for example the location of DNA lesions by base excision repair (BER) glycosylases and the regulation of tumor-suppressor genes such as p53 by detection of oxidative damage. However, the reproducible measurement and modelling of charge migration through DNA molecules at the nanometer scale remains a challenging and controversial subject even after more than a decade of intense efforts. Here we show, by analysing 162 disease-related genes from a variety of medical databases with a total of almost 20,000 observed pathogenic mutations, a significant difference in the electronic properties of the population of observed mutations compared to the set of all possible mutations. Our results have implications for the role of the electronic properties of DNA in cellular processes, and hint at the possibility of prediction, early diagnosis and detection of mutation hotspots.

Shih, Chi-Tin; Wells, Stephen A.; Hsu, Ching-Ling; Cheng, Yun-Yin; Römer, Rudolf A.

2012-02-01

354

Chemical treatment enhances skipping of a mutated exon in the dystrophin gene  

PubMed Central

Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease caused by a loss of the dystrophin protein. Control of dystrophin mRNA splicing to convert severe DMD to a milder phenotype is attracting much attention. Here we report a dystrophinopathy patient who has a point mutation in exon 31 of the dystrophin gene. Although the mutation generates a stop codon, a small amount of internally deleted, but functional, dystrophin protein is produced in the patient cells. An analysis of the mRNA reveals that the mutation promotes exon skipping and restores the open reading frame of dystrophin. Presumably, the mutation disrupts an exonic splicing enhancer and creates an exonic splicing silencer. Therefore, we searched for small chemicals that enhance exon skipping, and found that TG003 promotes the skipping of exon 31 in the endogenous dystrophin gene in a dose-dependent manner and increases the production of the dystrophin protein in the patient's cells. PMID:21556062

Nishida, Atsushi; Kataoka, Naoyuki; Takeshima, Yasuhiro; Yagi, Mariko; Awano, Hiroyuki; Ota, Mitsunori; Itoh, Kyoko; Hagiwara, Masatoshi; Matsuo, Masafumi

2011-01-01

355

Germline mutations in the PAF1 complex gene CTR9 predispose to Wilms tumour  

PubMed Central

Wilms tumour is a childhood kidney cancer. Here we identify inactivating CTR9 mutations in 3 of 35 Wilms tumour families, through exome and Sanger sequencing. By contrast, no similar mutations are present in 1,000 population controls (P<0.0001). Each mutation segregates with Wilms tumour in the family and a second mutational event is present in available tumours. CTR9 is a key component of the polymerase-associated factor 1 complex which has multiple roles in RNA polymerase II regulation and is implicated in embryonic organogenesis and maintenance of embryonic stem cell pluripotency. These data establish CTR9 as a Wilms tumour predisposition gene and suggest it acts as a tumour suppressor gene. PMID:25099282

Hanks, Sandra; Perdeaux, Elizabeth R.; Seal, Sheila; Ruark, Elise; Mahamdallie, Shazia S.; Murray, Anne; Ramsay, Emma; Del Vecchio Duarte, Silvana; Zachariou, Anna; de Souza, Bianca; Warren-Perry, Margaret; Elliott, Anna; Davidson, Alan; Price, Helen; Stiller, Charles; Pritchard-Jones, Kathy; Rahman, Nazneen

2014-01-01

356

Multiple mutations in a specific gene in a small geographic area: A common phenomenon  

SciTech Connect

We read with interest the article from Allamand et al., which demonstrates in a genetic isolate the presence of at least six different haplotypes in the limb-girdle muscular dystrophy type 2A chromosome. Several hypotheses were proposed by the authors to explain this finding, but, after the identification of calpain, the gene involved in the disorder, multiple mutations were proved to be at the origin of this observation. The authors proposed that both the presence of multiple distinct calpain mutations within the Reunion Island pedigrees and the relatively low frequency of the disease in the isolate may be explained by a digenic inheritance of the disorder. Their hypothesis postulates that, although calpain mutations may be frequent in all populations, the disease manifestations are controlled by another frequently mutated nuclear or mitochondrial gene in the Reunion isolate. 8 refs.

Zlotogora, J.; Bach, G.; Gieselmann, V.

1996-01-01

357

Hypotrichosis-lymphedema-telangiectasia-renal defect associated with a truncating mutation in the SOX18 gene.  

PubMed

SOX18 mutations in humans are associated with both recessive and dominant hypotrichosis-lymphedema-telangiectasia syndrome (HLTS). We report two families with affected children carrying a SOX18 mutation: a living patient and his stillborn brother from Canada and a Belgian patient. The two living patients were diagnosed with HLTS and DNA analysis for the SOX18 gene showed that both had the identical heterozygous C?>?A transversion, resulting in a pre-mature truncation of the protein, lacking the transactivation domain. Both living patients developed renal failure with severe hypertension in childhood for which both underwent renal transplantation. To our best knowledge this is the first report of renal failure associated with heterozygous mutations in the SOX18 gene. We conclude that this specific mutation results in a new, autosomal dominant condition and propose the acronym HLT-renal defect syndrome for HLTRS. PMID:24697860

Moalem, S; Brouillard, P; Kuypers, D; Legius, E; Harvey, E; Taylor, G; Francois, M; Vikkula, M; Chitayat, D

2015-04-01

358

Arrhythmia-associated cardiac Ca˛(+) cycling proteins and gene mutations.  

PubMed

Calcium is an important mediator in cardiac excitation and disorders in cardiac Ca(2+) homeostasis have great influence on the cardiac action potential. Therefore dysfunction in regulatory proteins that are involved in Ca(2+) handling can lead to the occurrence of severe arrhythmia. Although mutations in Ca(2+) regulating proteins are quite rare, they can offer general insights into arrhythmogenesis. Here, we briefly review some important aspects of arrhythmia-associated mutations in Ca(2+) regulating proteins with special emphasis to its associated pathophysiology. PMID:22733365

Kochhäuser, Simon; Schulze-Bahr, Eric; Kirchhefer, Uwe

2012-07-01

359

Transcription Profiling and Mutation Detection of Soybean Homoeologous Genes  

Technology Transfer Automated Retrieval System (TEKTRAN)

The soybean genome maintains numerous gene duplications, many of which are derived from ancient large-scale duplication. We are interested in exploring the evolutionary fate of duplicated genes and the extent to which gene duplication affects selectable trait variation. We are applying quantitative ...

360

Molecular definition of an allelic series of mutations disrupting the mouse Lmx1a (dreher) gene.  

PubMed

Mice homozygous for the dreher (dr) mutation are characterized by pigmentation and skeletal abnormalities and striking behavioral phenotypes, including ataxia, vestibular deficits, and hyperactivity. The ataxia is associated with a cerebellar malformation that is remarkably similar to human Dandy-Walker malformation. Previously, positional cloning identified mutations in LIM homeobox transcription factor 1 alpha gene (Lmx1a) in three dr alleles. Two of these alleles, however, are extinct and unavailable for further analysis. In this article we report a new spontaneous dr allele and describe the Lmx1a mutations in this and six additional dr alleles. Strikingly, deletion null, missense, and frameshift mutations in these alleles all cause similar cerebellar malformations, suggesting that all dr mutations analyzed to date are null alleles. PMID:17019651

Chizhikov, Victor; Steshina, Ekaterina; Roberts, Richard; Ilkin, Yesim; Washburn, Linda; Millen, Kathleen J

2006-10-01

361

Frequent NF2 gene transcript mutations in sporadic meningiomas and vestibular schwannomas  

SciTech Connect

The gene for the hereditary disorder neurofibromatosis type 2 (NF2), which predisposes for benign CNS tumors such as vestibular schwannomas and meningiomas, has been assigned to chromosome 22 and recently has been isolated. Mutations in the NF2 gene were found in both sporadic meningiomas and vestibular schwannomas. However, so far only 6 of the 16 exons of the gene have been analyzed. In order to extend the analysis of an involvement of the NF2 gene in the sporadic counterparts of these NF2-related tumors, the authors have used reverse transcriptase-PCR amplification followed by SSCP and DNA sequence analysis to screen for mutations in the coding region of the NF2 gene. Analysis of the NF2 gene transcript in 53 unrelated patients with meningiomas and vestibular schwannomas revealed mutations in 32% of the sporadic meningiomas (n = 44), in 50% of the sporadic vestibular schwannomas (n = 4), in 100% of the tumors found in NF2 patients (n = 2), and in one of three tumors from multiple-meningioma patients. Of the 18 tumors in which a mutation in the NF2 gene transcript was observed and the copy number of chromosome 22 could be established, 14 also showed loss of (parts of) chromosome 22. This suggests that in sporadic meningiomas and NF2-associated tumors the NF2 gene functions as a recessive tumor-suppressor gene. The mutations detected resulted mostly in frameshifts, predicting truncations starting within the N-terminal half of the putative protein. 23 refs., 2 figs. 3 tabs.

Deprez, R.H.L.; Groen, N.A.; Zwarthoff, E.C.; Hagemeijer, A.; Van Drunen, E.; Bootsma, D.; Koper, J.W.; Avezaat, C.J.J. (Erasmus Univ., Rotterdam (Netherlands)); Bianchi, A.B.; Seizinger, B.R. (Bristol Myers-Squibb Pharmaceutical Research Institute, Princeton, NY (United States))

1994-06-01

362

Mutational Screening of LCA Genes Emphasizing RPE65 in South Indian Cohort of Patients  

PubMed Central

Background Leber congenital amaurosis (LCA) is the most severe form of inherited retinal visual impairment in children. So far, mutations in more than 20 genes have been known to cause LCA and among them, RPE65 is a suitable candidate for gene therapy. The mutational screenings of RPE65 and other LCA genes are requisite in support of emerging gene specific therapy for LCA. Therefore, we have carried out a comprehensive LCA genes screening using a combined approach of direct sequencing and DNA microarray based Asper chip analysis. Methodology/Principal Findings Thirty clinically diagnosed index LCA cases from Southern India were screened for coding and flanking intronic regions of RPE65 through direct sequencing. Among thirty, 25 cases excluded from RPE65 mutations were subjected to Asper chip analysis, testing 784 known pathogenic variations in 15 major LCA genes. In RPE65 screening, four different pathogenic variations including two novel (c.361insT & c.939T>A) and two known (c.394G>A & c.361delT) mutations were identified in five index cases. In the chip analysis, seven known pathogenic mutations were identified in six index cases, involving genes GUCY2D, RPGRIP1, AIPL1, CRX and IQCB1. Overall, 11 out of 30 LCA cases (36.6%) revealed pathogenic variations with the involvement of RPE65 (16.6%), GUCY2D (10%), RPGRIP1 (3.3%), AIPL1 (3.3%) and CRX & IQCB1 (3.3%). Conclusions/Significance Our study suggests that such combined screening approach is productive and cost-effective for mutation detection and can be applied in Indian LCA cohort for molecular diagnosis and genetic counselling. PMID:24066033

Verma, Anshuman; Perumalsamy, Vijayalakshmi; Shetty, Shashikant; Kulm, Maigi; Sundaresan, Periasamy

2013-01-01

363

Screening analysis of candidate gene mutations in a kindred with polycystic liver disease  

PubMed Central

AIM: To find potential mutable sites by detecting mutations of the candidate gene in a kindred with polycystic liver disease (PCLD). METHODS: First, we chose a kindred with PCLD and obtained five venous blood samples of this kindred after the family members signed the informed consent form. In the kindred two cases were diagnosed with PCLD, and the left three cases were normal individuals. All the blood samples were preserved at -85?°C. Second, we extracted the genomic DNA from the venous blood samples of the kindred using a QIAamp DNA Mini Kit and then performed long-range polymerase chain reaction (PCR) with different primers. The exons of PKD1 were all sequenced with the forward and reverse primers to ensure the accuracy of the results. Next, we purified the PCR products and directly sequenced them using Big Dye Terminator Chemistry version 3.1. The sequencing reaction was conducted with BiomekFX (Beckman). Finally, we analyzed the results. RESULTS: A total of 42 normal exons were identified in detecting mutations of the PKD1 gene. A synonymous mutation occurred in exon 5. The mutation was a homozygous T in the proband and was C in the reference sequence. This mutation was located in the third codon and did not change the amino acid encoded by the codon. Missense mutations occurred in exons 11 and 35. These mutations were located in the second codon; they changed the amino acid sequence and existed in the dbSNP library. A nonsense mutation occurred in exon 15. The mutation was a heterozygous CT in the proband and was C in the reference sequence. This mutation was located in the first codon and resulted in a termination codon. This mutation had an obvious influence on the encoded protein and changed the length of the protein from 4303 to 2246 amino acids. This was a new mutation that was not present in the dbSNP library. CONCLUSION: The nonsense mutation of exon 15 existed in the proband and in the third individual. Additionally, the proband was heterozygous for this mutation, so the mutable site was a pathogenic mutation. PMID:25741140

Jin, Song; Cui, Kai; Sun, Zi-Qiang; Shen, Yang-Yang; Li, Pang; Wang, Zhen-Dan; Li, Fei-Fei; Gong, Ke-Nan; Li, Sheng

2015-01-01

364

Mutations of the flavin-containing monooxygenase gene (FMO3) cause trimethylaminuria, a defect in detoxication  

Microsoft Academic Search

Individuals with the recessive condition trimethyl- aminuria exhibit variation in metabolic detoxication of xenobiotics by hepatic flavin-containing mono- oxygenases. We show here that mutations in the human flavin-containing monooxygenase isoform 3 gene (FMO3) impair N-oxygenation of xenobiotics and are responsible for the trimethylaminuria phenotype. Three disease-causing mutations in nine Australian-born probands have been identified which share a particular polymorphic haplotype.

E. P. Treacy; B. R. Akerman; L. M. L. Chow; R. Youil; C. Bibeau; J. Lin; A. G. Bruce; M. Knight; D. M. Danks; J. R. Cashman; S. M. Forrest

1998-01-01

365

Identification of a new Arylsulfatase A (ARSA) gene mutation in Tunisian patients with metachromatic leukodystrophy (MLD).  

PubMed

Metachromatic leukodystrophy (MLD) is an autosomal recessive, lysosomal storage disease caused by a deficiency of the enzyme arylsulfatase A (ARSA). The aim of the present study was to identify the molecular basis of MLD in Tunisian population. Two Tunisian patients with late infantile MLD were studied. Both patients were homozygous for a new missense mutation that causes a substitution of Trp in Gly p.W124G. This is the first mutation of ARSA gene described in Tunisian population. PMID:19699491

Dorboz, Imen; Eymard-Pierre, Eleonore; Kefi, Rym; Abdelhak, Sonia; Miladi, Najoua; Boespflug-Tanguy, Odile

2009-12-15

366

Neurofilament deficiency in quail caused by nonsense mutation in neurofilament-L gene  

Microsoft Academic Search

Abstract. The existence of a neurofilament-deficient mutant,of Japanese quail was recently documented (Yamasaki, H., C. Itakura, and M. Mizutani. 1991. Acta Neuropathol. 82:427--434), but the genetic events leading to the neurofilament,deficiency have yet to be determined. Our molecular,biological analyses revealed that the expression of neurofilament-L (NF-L) gene was specifically repressed in neurons,of this mutant. To search for mutation(s) responsible for

O. Ohara; Y Gahara; T Miyake; H Teraoka; T Kitamura

1993-01-01

367

Periventricular nodular heterotopia in patients with filamin-1 gene mutations: neuroimaging findings  

Microsoft Academic Search

Background. The filamin-1 (FLN-1) gene is responsible for periventricular nodular heterotopia (PNH), which is an X-linked dominant neuronal\\u000a migration disorder. Objective. To review the clinical and imaging findings in a series of patients with documented filamin-1 mutations.¶Materials and methods. A retrospective review of the medical records and MR studies of a series of patients with PNH and confirmed FLN-1 mutations

T. Y. Poussaint; J. W. Fox; W. B. Dobyns; R. Radtke; I. E. Scheffer; S. F. Berkovic; P. D. Barnes; P. R. Huttenlocher; C. A. Walsh

2000-01-01

368

Mutations in the gene for X-linked adrenoleukodystrophy in patients with different clinical phenotypes.  

PubMed Central

Recently, the gene for the most common peroxisomal disorder, X-linked adrenoleukodystrophy (X-ALD), has been described encoding a peroxisomal membrane transporter protein. We analyzed the entire protein-coding sequence of this gene by reverse-transcription PCR, SSCP, and DNA sequencing in five patients with different clinical expression of X-ALD and in their female relatives; these clinical expressions were cerebral childhood ALD, adrenomyeloneuropathy (AMN), and "Addison disease only" (ADO) phenotype. In the three patients exhibiting the classical picture of severe childhood ALD we identified in the 5' portion of the X-ALD gene a 38-bp deletion that causes a frameshift mutation, a 3-bp deletion leading to a deletion of an amino acid in the ATP-binding domain of the ALD protein, and a missense mutation. In the patient with the clinical phenotype of AMN, a nonsense mutation in codon 212, along with a second site mutation at codon 178, was observed. Analysis of the patient with the ADO phenotype revealed a further missense mutation at a highly conserved position in the ALDP/PMP70 comparison. The disruptive nature of two mutations (i.e., the frameshift and the nonsense mutation) in patients with biochemically proved childhood ALD and AMN further strongly supports the hypothesis that alterations in this gene play a crucial role in the pathogenesis of X-ALD. Since the current biochemical techniques for X-ALD carrier detection in affected families lack sufficient reliability, our procedure described for systematic mutation scanning is also capable of improving genetic counseling and prenatal diagnosis. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7717396

Braun, A; Ambach, H; Kammerer, S; Rolinski, B; Stöckler, S; Rabl, W; Gärtner, J; Zierz, S; Roscher, A A

1995-01-01

369

Callipyge mutation affects gene expression in cis: A potential role for chromatin structure  

Microsoft Academic Search

Muscular hypertrophy in callipyge sheep results from a single nucleotide substitution located in the genomic interval between the imprinted Delta, Drosophila, Homolog-like 1 (DLK1) and Maternally Expressed Gene 3 (MEG3). The mechanism linking the mutation to muscle hypertrophy is unclear but involves DLK1 overexpression. The mutation is contained within CLPG1 transcripts produced from this region. Herein we show that CLPG1

Susan K. Murphy; Catherine M. Nolan; Zhiqing Huang; Katerina S. Kucera; Brad A. Freking; Timothy P. L. Smith; Kreg A. Leymaster; Jennifer R. Weidman; Randy L. Jirtle

2006-01-01

370

The Pathogenic Role of Point Mutations Affecting the Translational Initiation Codon of Mitochondrial Genes  

Microsoft Academic Search

The mutation T3308C results in a Met ? Thr change at the highly conserved amino acid position 1 of the mtDNA ND1 gene (M1T). To study its potential pathogenic effect we have carried out a combination of mitochondrial protein synthesis and Northern and Western analyses. Our data demonstrate that M1T mutation does not affect the efficiency of the synthesis of

Miguel Angel Fernández-Moreno; Belén Bornstein; Yolanda Campos; Joaqu??n Arenas; Rafael Garesse

2000-01-01

371

HIF gene mutation found in tumor cells offers new clues about cancer metabolism  

Cancer.gov

For the first time, a mutation in HIF2?, a specific group of genes known as transcription factors that is involved in red blood cell production and cell metabolism, has been identified in cancer tumor cells. Researchers from Huntsman Cancer Institute (HCI) at the University of Utah and the National Institutes of Health found the mutation in tumor cells of two patients with the rare cancers paraganglioma/pheochromocytoma and somatostatinoma.

372

NonTarget Gene Mutations in the Development of Fluoroquinolone Resistance in Escherichia coli  

Microsoft Academic Search

Mutations in loci other than genes for the target topoisomerases of fluoroquinolones, gyrA and parC, may play a role in the development of fluoroquinolone resistance in Escherichia coli. A series of mutants with increasing resistance to ofloxacin was obtained from an E. coli K-12 strain and five clinical isolates. First-step mutants acquired a gyrA mutation. Second-step mutants reproducibly acquired a

W. V. Kern; M. Oethinger; A. S. Jellen-Ritter; S. B. Levy

2000-01-01

373

Molecular basis of childhood deafness resulting from mutations in the GJB2 (connexin 26) gene  

Microsoft Academic Search

Mutations in the GJB2 gene have been identified in many patients with childhood deafness, 35delG being the most common mutation in Caucasoid populations. We have analyzed a total of 576 families\\/unrelated patients with recessive or sporadic deafness from Italy and Spain, 193 of them being referred as autosomal recessive, and the other 383 as apparently sporadic cases (singletons). Of the

Raquel Rabionet; Leopoldo Zelante; Núria López-Bigas; L. D'Agruma; S. Melchionda; G. Restagno; M. L. Arbonés; P. Gasparini; X. Estivill

2000-01-01

374

Hypogonadism in a Patient with a Mutation in the Luteinizing Hormone Beta-Subunit Gene  

Microsoft Academic Search

A 30-year-old man who presented with delayed puberty and infertility was found to have hypogonadism associated with an absence of circulating luteinizing hormone. The pa- tient had a homozygous missense mutation in the gene that encodes the beta subunit of luteinizing hormone (Gly36Asp), a mutation that disrupted a vital cystine knot motif and abrogated the heterodimerization and secretion of luteinizing

Hernán Valdes-Socin; Roberto Salvi; Adrian F. Daly; Rolf C. Gaillard; Pascale Quatresooz; Pierre-Marie Tebeu; François P. Pralong; Albert Beckers

2004-01-01

375

A novel MEFV gene mutation (A511V) in a Chilean FMF patient  

Microsoft Academic Search

Familial Mediterranean fever (FMF) is an autosomal recessive disease which is characterized by recurrent fever and inflammation of serous membranes. A Chilean FMF patient was investigated for MEFV mutations. After DNA extraction, exons 3, 5, 10 and 3?UTR region of MEFV gene were analyzed by DNA sequencing while E148Q and R202Q mutations of exon 2 were detected by RFLP. A

Nejat Akar; Ay?enur Öztürk; Çi?dem Arslan; Ece Akar; Silvia Castillo Taucher; Cristobal Passalacqua

2011-01-01

376

Mutation of the PIK3CA gene in ovarian and breast cancer.  

PubMed

Phosphatidylinositol 3'-kinases are lipid kinases with important roles in neoplasia. Recently, a very high frequency of somatic mutations in PIK3CA has been reported among a large series of colorectal cancers. However, the relevance of PIK3CA mutation in other cancer types remains unclear because of the limited number of tumors investigated. We have screened a total of 284 primary human tumors for mutations in all coding exons of PIK3CA using a combination of single stranded conformational polymorphism and denaturing high-performance liquid chromatography analysis. Among 70 primary breast cancers, 40% (28 of 70) harbored mutations in PIK3CA, making it the most common mutation described to date in this cancer type. Mutations were not associated with histologic subtype, estrogen receptor status, grade or presence of tumor in lymph nodes. Among the primary epithelial ovarian cancers only 11 of 167 (6.6%) contain somatic mutations, but there was a clear histologic subtype bias in their distribution. Only 2 of 88 (2.3%) of serous carcinomas had PIK3CA mutations compared with 8 of 40 (20.0%) endometrioid and clear cell cancers, which was highly significant (P = 0.001). In contrast, PIK3CA gene amplification (>7-fold) was common among all histologic subtypes (24.5%) and was inversely associated with the presence of mutations. Overall, PIK3CA mutation or gene amplification was detected in 30.5% of all ovarian cancers and 45% of the endometrioid and clear cell subtypes. Our study is the first direct evidence that PIK3CA is an oncogene in ovarian cancer and greatly extends recent findings in breast cancer. PMID:15520168

Campbell, Ian G; Russell, Sarah E; Choong, David Y H; Montgomery, Karen G; Ciavarella, Marianne L; Hooi, Christine S F; Cristiano, Briony E; Pearson, Richard B; Phillips, Wayne A

2004-11-01

377

Origin and Ascendancy of a Chimeric Fusion Gene: The ?/?-Globin Gene of Paenungulate Mammals  

PubMed Central

The ?-globin gene (HBD) of eutherian mammals exhibits a propensity for recombinational exchange with the closely linked ?-globin gene (HBB) and has been independently converted by the HBB gene in multiple lineages. Here we report the presence of a chimeric ?/? fusion gene in the African elephant (Loxodonta africana) that was created by unequal crossing-over between misaligned HBD and HBB paralogs. The recombinant chromosome that harbors the ?/? fusion gene in elephants is structurally similar to the “anti-Lepore” duplication mutant of humans (the reciprocal exchange product of the hemoglobin Lepore deletion mutant). However, the situation in the African elephant is unique in that the chimeric ?/? fusion gene supplanted the parental HBB gene and is therefore solely responsible for synthesizing the ?-chain subunits of adult hemoglobin. A phylogenetic survey of ?-like globin genes in afrotherian and xenarthran mammals revealed that the origin of the chimeric ?/? fusion gene and the concomitant inactivation of the HBB gene predated the radiation of “Paenungulata,” a clade of afrotherian mammals that includes three orders: Proboscidea (elephants), Sirenia (dugongs and manatees), and Hyracoidea (hyraxes). The reduced fitness of the human Hb Lepore deletion mutant helps to explain why independently derived ?/? fusion genes (which occur on an anti-Lepore chromosome) have been fixed in a number of mammalian lineages, whereas the reciprocal ?/? fusion gene (which occurs on a Lepore chromosome) has yet to be documented in any nonhuman mammal. This illustrates how the evolutionary fates of chimeric fusion genes can be strongly influenced by their recombinational mode of origin. PMID:19332641

Opazo, Juan C.; Sloan, Angela M.; Campbell, Kevin L.

2009-01-01

378

2004 Annual Meeting - Genes, Mutations and Disease: The Environmental Connection  

SciTech Connect

The Meeting consisted of 9 Symposia, 4 Keynote Lectures, 3 Platform Sessions and 4 Poster Sessions. In addition there were Breakfast Meetings for Special Interest Groups designed to inform attendees about the latest advances in environmental mutagenesis research. Several of the topics to be covered at this broad meeting will be of interest to the Department of Energy, Office of Science. The relevance of this meeting to the DOE derives from the fact that low dose radiation may represent one of the most significant sources of human mutations that are attributable to the environment. The EMS membership, and those who attended the EMS Annual Meeting were interested in both chemical and radiation induced biological effects, such as cell death, mutation, teratogenesis, carcinogenesis and aging. These topics thate were presented at the 2004 EMS Annual meeting that were of clear interest to DOE include: human variation in cancer susceptibility, unusual mechanisms of mutation, germ and stem cell mutagenesis, recombination and the maintenance of genomic stability, multiple roles for DNA mismatch repair, DNA helicases, mutation, cancer and aging, Genome-wide transcriptional responses to environmental change, Telomeres and genomic stability: when ends don?t meet, systems biology approach to cell phenotypic decision processes, and the surprising biology of short RNAs. Poster and platform sessions addressed topics related to environmental mutagen exposure, DNA repair, mechanisms of mutagenesis, epidemiology, genomic and proteomics and bioinformatics. These sessions were designed to give student, postdocs and more junior scientists a chance to present their workl.

Leona D. Samson, Ph.D.

2004-08-23

379

Mutations of mitotic checkpoint genes in human cancers  

Microsoft Academic Search

Genetic instability was one of the first characteristics to be postulated to underlie neoplasia. Such genetic instability occurs in two different forms. In a small fraction of colorectal and some other cancers, defective repair of mismatched bases results in an increased mutation rate at the nucleotide level and consequent widespread microsatellite instability. In most colorectal cancers, and probably in many

Daniel P. Cahill; Christoph Lengauer; Jian Yu; Gregory J. Riggins; James K. V. Willson; Sanford D. Markowitz; Kenneth W. Kinzler; Bert Vogelstein

1998-01-01

380

The Berkeley Drosophila Genome Project gene disruption project: Single P-element insertions mutating 25% of vital Drosophila genes.  

PubMed Central

A fundamental goal of genetics and functional genomics is to identify and mutate every gene in model organisms such as Drosophila melanogaster. The Berkeley Drosophila Genome Project (BDGP) gene disruption project generates single P-element insertion strains that each mutate unique genomic open reading frames. Such strains strongly facilitate further genetic and molecular studies of the disrupted loci, but it has remained unclear if P elements can be used to mutate all Drosophila genes. We now report that the primary collection has grown to contain 1045 strains that disrupt more than 25% of the estimated 3600 Drosophila genes that are essential for adult viability. Of these P insertions, 67% have been verified by genetic tests to cause the associated recessive mutant phenotypes, and the validity of most of the remaining lines is predicted on statistical grounds. Sequences flanking >920 insertions have been determined to exactly position them in the genome and to identify 376 potentially affected transcripts from collections of EST sequences. Strains in the BDGP collection are available from the Bloomington Stock Center and have already assisted the research community in characterizing >250 Drosophila genes. The likely identity of 131 additional genes in the collection is reported here. Our results show that Drosophila genes have a wide range of sensitivity to inactivation by P elements, and provide a rationale for greatly expanding the BDGP primary collection based entirely on insertion site sequencing. We predict that this approach can bring >85% of all Drosophila open reading frames under experimental control. PMID:10471706

Spradling, A C; Stern, D; Beaton, A; Rhem, E J; Laverty, T; Mozden, N; Misra, S; Rubin, G M

1999-01-01

381

Frameshift mutation in the PTCH2 gene can cause nevoid basal cell carcinoma syndrome.  

PubMed

Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterized by developmental defects and tumorigenesis. The gene responsible for NBCCS is PTCH1, encoding a receptor for the secreted protein, sonic hedgehog. Recently, a Chinese family with NBCCS carrying a missense mutation in PTCH2, a close homolog of PTCH1, was reported. However, the pathological significance of missense mutations should be discussed cautiously. Here, we report a 13-year-old girl diagnosed with NBCCS based on multiple keratocystic odontogenic tumors and rib anomalies carrying a frameshift mutation in the PTCH2 gene (c.1172_1173delCT). Considering the deleterious nature of the frameshift mutation, our study further confirmed a causative role for the PTCH2 mutation in NBCCS. The absence of typical phenotypes in this case such as palmar/plantar pits, macrocephaly, falx calcification, hypertelorism and coarse face, together with previously reported cases, suggested that individuals with NBCCS carrying a PTCH2 mutation may have a milder phenotype than those with a PTCH1 mutation. PMID:23479190

Fujii, Katsunori; Ohashi, Hirofumi; Suzuki, Maiko; Hatsuse, Hiromi; Shiohama, Tadashi; Uchikawa, Hideki; Miyashita, Toshiyuki

2013-12-01

382

Two novel NIPBL gene mutations in Chinese patients with Cornelia de Lange syndrome.  

PubMed

Cornelia de Lange syndrome (CdLS) is a dominantly inherited developmental disorder characterized by distinctive facial features, mental retardation, and upper limb defects, with the involvement of multiple organs and systems. To date, mutations have been identified in five genes responsible for CdLS: NIPBL, SMC1A, SMC3, RAD21, and HDAC8. Here, we present a clinical and molecular characterization of five unrelated Chinese patients whose clinical presentation is consistent with that of CdLS. There were no chromosomal abnormalities in the five children. In three patients, DNA sequencing revealed a previously reported frameshift mutation c.2479delA (p.Arg827GlyfsX20), and two novel mutations including a heterozygous mutation c.6272 G>T (p.Cys2091Phe) and a frameshift mutation c.1672delA (p.Thr558LeufsX7) in NIPBL. For the remaining patients, large deletions and/or duplications within the NIPBL gene were excluded as playing a role in the pathogenesis, by Multiplex Ligation-dependent Probe Amplification (MLPA) analysis. These findings broaden the mutation spectrum of NIPBL and further our understanding of the diverse and variable effects of NIPBL mutations on CdLS. PMID:25447906

Mei, Libin; Liang, Desheng; Huang, Yanru; Pan, Qian; Wu, Lingqian

2015-01-25

383

Parental source effect of inherited mutations in the dystrophin gene of mice and men  

SciTech Connect

Skewed X-inactivation has been suspected the genetic cause for some manifesting female carriers of BMD and DMD. To test whether a parental source effect on the protein expression of the dystrophin gene exists, we have set up backcrosses of mdx mice to wild type strains, enabling us to study the effect of the well-defined origin of the mutation on the dystrophin expression. In skeletal muscle sections the immunohistological staining patterns of dystrophin antibodies were showing a significant difference in the proportion of dystrophin positive versus negative fibers, suggesting a lower expression of paternally inherited mdx mutations. These data are in concordance with the pyruvate kinase (PK) levels in the serum: PK levels were much higher when the mutation was of maternal origin as compared to PK levels in paternally derived mutations. In order to test this {open_quotes}paternal source effect{close_quotes} in humans, we checked obligatory carriers of Becker muscular dystrophy (BMD) for the origin of their mutations. Creatin kinase (CK) levels in 21 carriers with maternally derived mutations were compared to CK values from 8 heterozygotes with mutations of paternal origin: CK (mat) = 140.3 IU/1 versus CK (pat) = 48.6 IU/I. The difference is statistically significant at the 5% level. These observations suggest either a differential X-inactivation or an imprinting of the dystrophin gene in mice and men.

Kress, W.; Grimm, T.; Mueller, C.R. [Institute of Human Genetics, Wuerburg (Germany); Bittner, R. [Institute of Anatomy, Wein (Australia)

1994-09-01

384

A large-scale gene-trap screen for insertional mutations in developmentally regulated genes in mice  

SciTech Connect

We have used a gene-trap vector and mouse embryonic stem (ES) cells to screen for insertional mutations in genes developmentally regulated at 8.5 days of embryogenesis (dpc). From 38,730 cell lines with vector insertions, 393 clonal integrations had disrupted active transcription units, as assayed by {beta}-galactosidase reporter gene expression. From these lines, 290 clones were recovered and injected into blastocysts to assay for reporter gene expression in 8.5-dpc chimeric mouse embryos. Of these, 279 clones provided a sufficient number of chimeric embryos for analysis. Thirty-six (13%) showed restricted patterns of reporter-gene expression, 88 (32%) showed widespread expression and 155 (55%) failed to show detectable levels of expression. Further analysis showed that approximately one-third of the clones that did not express detectable levels of the reporter gene at 8.5 dpc displayed reporter gene activity at 12.5 dpc. Thus, a large proportion of the genes that are expressed in ES cells are either temporally or spatially regulated during embryogenesis. These results indicate that gene-trap mutageneses in embryonic stem cells provide an effective approach for isolating mutations in a large number of developmentally regulated genes. 40 refs., 5 figs., 4 tabs.

Wurst, W.; Rossant, J.; Prideaux, V.; Kownacka, M.; Hill, D.P.; Guillemot, F.; Auerbach, A.; Cado, D.; Ang, S.L. [Mount Sinai Hospital, Toronto, Ontario (Canada); and others

1995-02-01

385

A Large-Scale Gene-Trap Screen for Insertional Mutations in Developmentally Regulated Genes in Mice  

PubMed Central

We have used a gene-trap vector and mouse embryonic stem (ES) cells to screen for insertional mutations in genes developmentally regulated at 8.5 days of embryogenesis (dpc). From 38,730 cell lines with vector insertions, 393 clonal integrations had disrupted active transcription units, as assayed by ?-galactosidase reporter gene expression. From these lines, 290 clones were recovered and injected into blastocysts to assay for reporter gene expression in 8.5-dpc chimeric mouse embryos. Of these, 279 clones provided a sufficient number of chimeric embryos for analysis. Thirty-six (13%) showed restricted patterns of reporter-gene expression, 88 (32%) showed widespread expression and 155 (55%) failed to show detectable levels of expression. Further analysis showed that approximately one-third of the clones that did not express detectable levels of the reporter gene at 8.5 dpc displayed reporter gene activity at 12.5 dpc. Thus, a large proportion of the genes that are expressed in ES cells are either temporally or spatially regulated during embryogenesis. These results indicate that gene-trap mutageneses in embryonic stem cells provide an effective approach for isolating mutations in a large number of developmentally regulated genes. PMID:7713439

Wurst, W.; Rossant, J.; Prideaux, V.; Kownacka, M.; Joyner, A.; Hill, D. P.; Guillemot, F.; Gasca, S.; Cado, D.; Auerbach, A.; Ang, S. L.

1995-01-01

386

A Restricted Spectrum of Mutations in the SMAD4 Tumor-Suppressor Gene Underlies Myhre Syndrome  

PubMed Central

Myhre syndrome is a developmental disorder characterized by reduced growth, generalized muscular hypertrophy, facial dysmorphism, deafness, cognitive deficits, joint stiffness, and skeletal anomalies. Here, by performing exome sequencing of a single affected individual and coupling the results to a hypothesis-driven filtering strategy, we establish that heterozygous mutations in SMAD4, which encodes for a transducer mediating transforming growth factor ? and bone morphogenetic protein signaling branches, underlie this rare Mendelian trait. Two recurrent de novo SMAD4 mutations were identified in eight unrelated subjects. Both mutations were missense changes altering Ile500 within the evolutionary conserved MAD homology 2 domain, a well known mutational hot spot in malignancies. Structural analyses suggest that the substituted residues are likely to perturb the binding properties of the mutant protein to signaling partners. Although SMAD4 has been established as a tumor suppressor gene somatically mutated in pancreatic, gastrointestinal, and skin cancers, and germline loss-of-function lesions and deletions of this gene have been documented to cause disorders that predispose individuals to gastrointestinal cancer and vascular dysplasias, the present report identifies a previously unrecognized class of mutations in the gene with profound impact on development and growth. PMID:22243968

Caputo, Viviana; Cianetti, Luciano; Niceta, Marcello; Carta, Claudio; Ciolfi, Andrea; Bocchinfuso, Gianfranco; Carrani, Eugenio; Dentici, Maria Lisa; Biamino, Elisa; Belligni, Elga; Garavelli, Livia; Boccone, Loredana; Melis, Daniela; Andria, Generoso; Gelb, Bruce D.; Stella, Lorenzo; Silengo, Margherita; Dallapiccola, Bruno; Tartaglia, Marco

2012-01-01

387

A restricted spectrum of mutations in the SMAD4 tumor-suppressor gene underlies Myhre syndrome.  

PubMed

Myhre syndrome is a developmental disorder characterized by reduced growth, generalized muscular hypertrophy, facial dysmorphism, deafness, cognitive deficits, joint stiffness, and skeletal anomalies. Here, by performing exome sequencing of a single affected individual and coupling the results to a hypothesis-driven filtering strategy, we establish that heterozygous mutations in SMAD4, which encodes for a transducer mediating transforming growth factor ? and bone morphogenetic protein signaling branches, underlie this rare Mendelian trait. Two recurrent de novo SMAD4 mutations were identified in eight unrelated subjects. Both mutations were missense changes altering Ile500 within the evolutionary conserved MAD homology 2 domain, a well known mutational hot spot in malignancies. Structural analyses suggest that the substituted residues are likely to perturb the binding properties of the mutant protein to signaling partners. Although SMAD4 has been established as a tumor suppressor gene somatically mutated in pancreatic, gastrointestinal, and skin cancers, and germline loss-of-function lesions and deletions of this gene have been documented to cause disorders that predispose individuals to gastrointestinal cancer and vascular dysplasias, the present report identifies a previously unrecognized class of mutations in the gene with profound impact on development and growth. PMID:22243968

Caputo, Viviana; Cianetti, Luciano; Niceta, Marcello; Carta, Claudio; Ciolfi, Andrea; Bocchinfuso, Gianfranco; Carrani, Eugenio; Dentici, Maria Lisa; Biamino, Elisa; Belligni, Elga; Garavelli, Livia; Boccone, Loredana; Melis, Daniela; Andria, Generoso; Gelb, Bruce D; Stella, Lorenzo; Silengo, Margherita; Dallapiccola, Bruno; Tartaglia, Marco

2012-01-13

388

Rare Mutations in Renal Sodium and Potassium Transporter Genes Exhibit Impaired Transport Function  

PubMed Central

Purpose of review Recent efforts to explore the genetic underpinnings of hypertension revealed rare mutations in kidney salt transport genes contribute to blood pressure variation and hypertension susceptibility in the general population. The current review focuses on these latest findings, highlighting a discussion about the rare mutations and how they affect transport function. Recent findings Rare mutations that confer a low blood pressure trait and resistance to hypertension have recently been extensively studied. Physiological and biochemical analyses of the effected renal salt transport molecules (NKCC2 (SLC12A1), ROMK (KCNJ1), and NCC (SLC12A3)) revealed that most of the mutations do, in fact, cause a loss of transport function. The mutations disrupt transport by many different mechanisms, including altering biosynthetic processing, trafficking, ion transport, and regulation. Summary New insights into the genetic basis of hypertension have recently emerged, supporting a major role of rare, rather than common, gene variants. Many different rare mutations have been found to affect the functions of different salt transporter genes by different mechanisms, yet all confer the same blood pressure phenotype. These studies reinforce the critical roles of the kidney, and renal salt transport in blood pressure regulation and hypertension. PMID:24253496

Welling, Paul A.

2014-01-01

389

Mutation of the PAX6 gene in patients with autosomal dominant keratitis  

SciTech Connect

Autosomal dominant keratitis (ADK) is an eye disorder chiefly characterized by corneal opacification and vascularization and by foveal hypoplasia. Aniridia (shown recently to result from mutations in the PAX6 gene) has overlapping clinical findings and a similar pattern of inheritance with ADK. On the basis of these similarities, we used a candidate-gene approach to investigate whether mutations in the PAX6 gene also result in ADK. Significant linkage was found between two polymorphic loci in the PAX6 region and ADK in a family with 15 affected members in four generations (peak LOD score = 4.45; {theta} = .00 with D11S914), consistent with PAX6 mutations being responsible for ADK. SSCP analysis and direct sequencing revealed a mutation in the PAX6 exon 11 splice-acceptor site. The predicted consequent incorrect splicing results in truncation of the PAX6 proline-serine-threonine activation domain. The Sey{sup Neu} mouse results from a mutation in the Pax-6 exon 10 splice-donor site that produces a PAX6 protein truncated from the same point as occurs in our family with ADK. Therefore, the Sey{sup Neu} mouse is an excellent animal model of ADK. The finding that mutations in PAX6 also underlie Peters anomaly implicates PAX6 broadly in human anterior segment malformations. 42 refs., 5 figs., 3 tabs.

Mirzayans, F.; Pearce, W.G.; MacDonald, I.M.; Walter, M.A. [Univ. of Alberta, Edmonton (Canada)

1995-09-01

390

Analysis of mutations in the entire coding sequence of the factor VIII gene  

SciTech Connect

Hemophilia A is a common X-linked recessive disorder of bleeding caused by deleterious mutations in the gene for clotting factor VIII. The large size of the factor VIII gene, the high frequency of de novo mutations and its tissue-specific expression complicate the detection of mutations. We have used a combination of RT-PCR of ectopic factor VIII transcripts and genomic DNA-PCRs to amplify the entire essential sequence of the factor VIII gene. This is followed by chemical mismatch cleavage analysis and direct sequencing in order to facilitate a comprehensive search for mutations. We describe the characterization of nine potentially pathogenic mutations, six of which are novel. In each case, a correlation of the genotype with the observed phenotype is presented. In order to evaluate the pathogenicity of the five missense mutations detected, we have analyzed them for evolutionary sequence conservation and for their involvement of sequence motifs catalogued in the PROSITE database of protein sites and patterns.

Bidichadani, S.I.; Lanyon, W.G.; Connor, J.M. [Glascow Univ. (United Kingdom)] [and others

1994-09-01

391

Identification of novel mutations in HEXA gene in children affected with Tay Sachs disease from India.  

PubMed

Tay Sachs disease (TSD) is a neurodegenerative disorder due to ?-hexosaminidase A deficiency caused by mutations in the HEXA gene. The mutations leading to Tay Sachs disease in India are yet unknown. We aimed to determine mutations leading to TSD in India by complete sequencing of the HEXA gene. The clinical inclusion criteria included neuroregression, seizures, exaggerated startle reflex, macrocephaly, cherry red spot on fundus examination and spasticity. Neuroimaging criteria included thalamic hyperdensities on CT scan/T1W images of MRI of the brain. Biochemical criteria included deficiency of hexosaminidase A (less than 2% of total hexosaminidase activity for infantile patients). Total leukocyte hexosaminidase activity was assayed by 4-methylumbelliferyl-N-acetyl-?-D-glucosamine lysis and hexosaminidase A activity was assayed by heat inactivation method and 4-methylumbelliferyl-N-acetyl-?-D-glucosamine-6-sulphate lysis method. The exons and exon-intron boundaries of the HEXA gene were bidirectionally sequenced using an automated sequencer. Mutations were confirmed in parents and looked up in public databases. In silico analysis for mutations was carried out using SIFT, Polyphen2, MutationT@ster and Accelrys Discovery Studio softwares. Fifteen families were included in the study. We identified six novel missense mutations, c.340 G>A (p.E114K), c.964 G>A (p.D322N), c.964 G>T (p.D322Y), c.1178C>G (p.R393P) and c.1385A>T (p.E462V), c.1432 G>A (p.G478R) and two previously reported mutations. c.1277_1278insTATC and c.508C>T (p.R170W). The mutation p.E462V was found in six unrelated families from Gujarat indicating a founder effect. A previously known splice site mutation c.805+1 G>C and another intronic mutation c.672+30 T>G of unknown significance were also identified. Mutations could not be identified in one family. We conclude that TSD patients from Gujarat should be screened for the common mutation p.E462V. PMID:22723944

Mistri, Mehul; Tamhankar, Parag M; Sheth, Frenny; Sanghavi, Daksha; Kondurkar, Pratima; Patil, Swapnil; Idicula-Thomas, Susan; Gupta, Sarita; Sheth, Jayesh

2012-01-01

392

‘RetinoGenetics’: a comprehensive mutation database for genes related to inherited retinal degeneration  

PubMed Central

Inherited retinal degeneration (IRD), a leading cause of human blindness worldwide, is exceptionally heterogeneous with clinical heterogeneity and genetic variety. During the past decades, tremendous efforts have been made to explore the complex heterogeneity, and massive mutations have been identified in different genes underlying IRD with the significant advancement of sequencing technology. In this study, we developed a comprehensive database, ‘RetinoGenetics’, which contains informative knowledge about all known IRD-related genes and mutations for IRD. ‘RetinoGenetics’ currently contains 4270 mutations in 186 genes, with detailed information associated with 164 phenotypes from 934 publications and various types of functional annotations. Then extensive annotations were performed to each gene using various resources, including Gene Ontology, KEGG pathways, protein–protein interaction, mutational annotations and gene–disease network. Furthermore, by using the search functions, convenient browsing ways and intuitive graphical displays, ‘RetinoGenetics’ could serve as a valuable resource for unveiling the genetic basis of IRD. Taken together, ‘RetinoGenetics’ is an integrative, informative and updatable resource for IRD-related genetic predispositions. Database URL: http://www.retinogenetics.org/. PMID:24939193

Ran, Xia; Cai, Wei-Jun; Huang, Xiu-Feng; Liu, Qi; Lu, Fan; Qu, Jia; Wu, Jinyu; Jin, Zi-Bing

2014-01-01

393

Strand specificity for UV-induced DNA repair and mutations in the Chinese hamster HPRT gene.  

PubMed Central

DNA excision repair modulates the mutagenic effect of many genotoxic agents. The recently observed strand specificity for removal of UV-induced cyclobutane dimers from actively transcribed genes in mammalian cells could influence the nature and distribution of mutations in a particular gene. To investigate this, we have analyzed UV-induced DNA repair and mutagenesis in the same gene, i.e. the hypoxanthine phosphoribosyl-transferase (hprt) gene. In 23 hprt mutants from V79 Chinese hamster cells induced by 2 J/m2 UV we found a strong strand bias for mutation induction: assuming that pre-mutagenic lesions occur at dipyrimidine sequences, 85% of the mutations could be attributed to lesions in the nontranscribed strand. Analysis of DNA repair in the hprt gene revealed that more than 90% of the cyclobutane dimers were removed from the transcribed strand within 8 hours after irradiation with 10 J/m2 UV, whereas virtually no dimer removal could be detected from the nontranscribed strand even up to 24 hr after UV. These data present the first proof that strand specific repair of DNA lesions in an expressed mammalian gene is associated with a strand specificity for mutation induction. Images PMID:1674998

Vrieling, H; Venema, J; van Rooyen, M L; van Hoffen, A; Menichini, P; Zdzienicka, M Z; Simons, J W; Mullenders, L H; van Zeeland, A A

1991-01-01

394

A Novel WASP Gene Mutation in a Chinese Boy with Wiskott-Aldrich Syndrome.  

PubMed

Wiskott-Aldrich syndrome (WAS) is a rare inherited X-linked recessive immunodeficiency disease characterized by eczema, thrombocytopenia, immune deficiency, and bloody diarrhea and is caused by WASP gene mutations. This study reports a case of WAS with a novel mutation. A newborn Chinese infant was admitted to the hospital because of intermittent bloody stools, recurrent infections, and persistent thrombocytopenia. Genetic analysis of the coding sequences and flanking splice sites of the WASP gene showed a novel WASP gene deletion mutation (1144delA) at exon 10. Family history showed that both his mother and aunt had a heterozygous genotype of the WASP gene. The infant died at the age of 4 months due to persistent thrombocytopenia and severe pneumonia. A novel WASP gene deletion (1144delA) at exon 10 was identified in a Chinese infant with WAS. This base deletion results in a frame-shift mutation of the gene for an early stop codon at amino acid 444. PMID:25332617

Wu, Hui; Hu, Cheng; Dang, Dan; Guo, Ying-Jie

2014-09-01

395

Ohno’s “Peril of Hemizygosity” Revisited: Gene Loss, Dosage Compensation, and Mutation  

PubMed Central

We explore the evolutionary origins of dosage compensation (DC) in sex chromosomes in the context of metabolic control theory. We consider first the cost of gene loss (hemizygosity) per se in reducing flux, and examine two relationships between flux and fitness (linear and Gaussian) to calculate a fitness cost of hemizygosity. Recognizing that new sex chromosomes are derived from autosomes, we also calculate the cost of unmasking deleterious mutations segregating on the nascent sex chromosomes as loci become hemizygous. The importance of deleterious mutations to the fitness cost of hemizygosity depends on their frequency, and on the relative costs of halving gene dose for wild-type alleles. We then consider the evolution of DC in response to gene loss, and include a cost of overexpression (i.e., DC such that expression exceeds the wild-type homozygote). Even with costs to excess flux, hypomorphic mutations can cause the optimal level of DC to be higher than 2-fold when the absolute cost of hemizygosity is small. Finally, we propose a three-step model of DC evolution: 1) once recombination ceases and the Y begins to deteriorate, genes from longer metabolic pathways should be lost first, as halving these genes does not drastically reduce flux or, thereby, fitness; 2) both the cost of hemizygosity and the presence of hypomorphic mutations will drive an increase in expression, that is, DC; 3) existing DC will now permit loss of genes in short pathways. PMID:23193178

Hall, David W.; Wayne, Marta L.

2013-01-01

396

Evaluation of the cationic trypsinogen gene for potential mutations in miniature schnauzers with pancreatitis  

PubMed Central

Abstract The purpose of this study was to evaluate the cationic trypsinogen gene in miniature schnauzers for possible mutations. Genetic mutations have been linked with hereditary pancreatitis in humans. Four miniature schnauzers were selected on the basis of a clinical history of pancreatitis. One healthy miniature schnauzer and 1 healthy mixed breed canine were enrolled as controls. DNA was extracted from these canines using a commercial kit. Primers were designed to amplify the entire canine cationic trypsinogen cDNA sequence. A polymerase chain reaction (PCR) was performed and products were purified and sequenced. All sequences were then compared. The healthy control canine, a healthy miniature schnauzer, and the 4 miniature schnauzers with pancreatitis showed identical sequences of the cationic trypsinogen gene to the published sequence. We conclude that, in contrast to humans with hereditary pancreatitis, mutations of the cationic trypsinogen gene do not play a major role in the genesis of pancreatitis in the miniature schnauzer. PMID:15581228

2004-01-01

397

Correlation of Gene Expression and Genome Mutation in Single B-Cells  

PubMed Central

High-throughput measurement of gene-expression and immune receptor repertoires have recently become powerful tools in the study of adaptive immune response. However, despite their now-widespread use, both tend to discard cell identity by treating cell populations in bulk, and therefore lose the correlation between genetic variability and gene-expression at the single cell level. In order to recover this information, we developed a method to simultaneously measure gene expression profiles and genome mutations in single cells. We applied this method by quantifying the relationships between gene expression and antibody mutation in ensembles of individual B-cells from immunized mice. The results reveal correlations reflecting the manner in which information propagates between a B-cell’s antigen receptors, its gene expression, and its mutagenic machinery, and demonstrate the power of this approach to illuminate both heterogeneity and physiology in cell populations. PMID:23840752

Weinstein, Joshua A.; Zeng, Xun; Chien, Yueh-Hsiu; Quake, Stephen R.

2013-01-01

398

ONCOGENE MUTATION PROFILING OF PEDIATRIC SOLID TUMORS REVEALS SIGNIFICANT SUBSETS OF EMBRYONAL RHABDOMYOSARCOMA AND NEUROBLASTOMA WITH MUTATED GENES IN GROWTH SIGNALING PATHWAYS  

PubMed Central

Compared to the numerous broad screens for oncogene mutations in adult cancers, very few have been performed in pediatric solid tumors. To identify novel mutations and potential therapeutic targets in pediatric cancers, we performed a high-throughput Sequenom-based analysis in large sets of several major pediatric solid cancers, including neuroblastoma (NB), Ewing sarcoma (ES), rhabdomyosarcoma (RMS), and desmoplastic small round cell tumor (DSRCT). Experimental Design We designed a highly multiplexed Sequenom-based assay to interrogate 275 recurrent mutations across 29 genes. Genomic DNA was extracted from 192 NB, 75 ES, 89 RMS, and 24 DSRCT samples. All mutations were verified by Sanger sequencing. Results Mutations were identified in 13% of NB samples, 4% of ES samples, 21.1% of RMS samples, and no DSRCT samples. ALK mutations were present in 10.4% of NB samples. The remainder of NB mutations involved the BRAF, RAS, and MAP2K1 genes and were absent in samples harboring ALK mutations. Mutations were more common in embryonal RMS (ERMS) samples (28.3%) than alveolar RMS (ARMS) (3.5%). In addition to previously identified RAS and FGFR4 mutations, we report for the first time PIK3CA and CTNNB1 (Beta-Catenin) mutations in 4.9% and 3.3% of ERMS, respectively. Conclusions In ERMS, ES, and NB, we identified novel occurrences of several oncogene mutations recognized as drivers in other cancers. Overall, NB and ERMS contain significant subsets of cases with non-overlapping mutated genes in growth signaling pathways. Tumor profiling can identify a subset of pediatric solid tumor patients as candidates for kinase inhibitors or RAS-targeted therapies. PMID:22142829

Shukla, Neerav; Ameur, Nabahet; Yilmaz, Ismail; Nafa, Khedoudja; Lau, Chyau-Yueh; Marchetti, Angela; Borsu, Laetitia; Barr, Frederic G.; Ladanyi, Marc

2012-01-01

399

Mutations in the collagen XII gene define a new form of extracellular matrix-related myopathy.  

PubMed

Bethlem myopathy (BM) [MIM 158810] is a slowly progressive muscle disease characterized by contractures and proximal weakness, which can be caused by mutations in one of the collagen VI genes (COL6A1, COL6A2 and COL6A3). However, there may be additional causal genes to identify as in ?50% of BM cases no mutations in the COL6 genes are identified. In a cohort of -24 patients with a BM-like phenotype, we first sequenced 12 candidate genes based on their function, including genes for known binding partners of collagen VI, and those enzymes involved in its correct post-translational modification, assembly and secretion. Proceeding to whole-exome sequencing (WES), we identified mutations in the COL12A1 gene, a member of the FACIT collagens (fibril-associated collagens with interrupted triple helices) in five individuals from two families. Both families showed dominant inheritance with a clinical phenotype resembling classical BM. Family 1 had a single-base substitution that led to the replacement of one glycine residue in the triple-helical domain, breaking the Gly-X-Y repeating pattern, and Family 2 had a missense mutation, which created a mutant protein with an unpaired cysteine residue. Abnormality at the protein level was confirmed in both families by the intracellular retention of collagen XII in patient dermal fibroblasts. The mutation in Family 2 leads to the up-regulation of genes associated with the unfolded protein response (UPR) pathway and swollen, dysmorphic rough-ER. We conclude that the spectrum of causative genes in extracellular matrix (ECM)-related myopathies be extended to include COL12A1. PMID:24334769

Hicks, Debbie; Farsani, Golara Torabi; Laval, Steven; Collins, James; Sarkozy, Anna; Martoni, Elena; Shah, Ashoke; Zou, Yaqun; Koch, Manuel; Bönnemann, Carsten G; Roberts, Mark; Lochmüller, Hanns; Bushby, Kate; Straub, Volker

2014-05-01

400

A Mutation Affecting the Regulation of a Seca-Lacz Fusion Defines a New Sec Gene  

PubMed Central

It was shown previously that the secA gene of Escherichia coli is derepressed in cells that have a defect in protein export. Here it is demonstrated that the ?-galactosidase produced by a secA-lacZ gene fusion strain is regulated in the same way. Studies on the fusion strain reveal that the promoter or a site involved in regulation of the secA gene is located considerably upstream from the structural gene. The properties of the fusion strain provide a new selection for mutants that are defective in protein export. Selection for increased lac expression of a secA-lacZ fusion strain yields mutations in three of the known sec genes, secA, secD and prlA/secY. In addition, mutations in several genes not previously known to affect secA expression were obtained. A mutation in one of these genes causes a pleiotropic defect in protein export and a cold-sensitive growth defect; this gene, which maps at approximately 90 min on the bacterial chromosome, has been named secE. PMID:3284784

Riggs, P. D.; Derman, A. I.; Beckwith, J.

1988-01-01

401

Novel Mutations in the SCNN1A Gene Causing Pseudohypoaldosteronism Type 1  

PubMed Central

Pseudohypoaldosteronism type 1 (PHA1) is a rare inherited disease characterized by resistance to the actions of aldosterone. Mutations in the subunit genes (SCNN1A, SCNN1B, SCNN1G) of the epithelial sodium channel (ENaC) and the NR3C2 gene encoding the mineralocorticoid receptor, result in systemic PHA1 and renal PHA1 respectively. Common clinical manifestations of PHA1 include salt wasting, hyperkalaemia, metabolic acidosis and elevated plasma aldosterone levels in the neonatal period. In this study, we describe the clinical and biochemical manifestations in two Chinese patients with systemic PHA1. Sequence analysis of the SCNN1A gene revealed a compound heterozygous mutation (c.1311delG and c.1439+1G>C) in one patient and a homozygous mutation (c.814_815insG) in another patient, all three variants are novel. Further analysis of the splicing pattern in a minigene construct showed that the c.1439+1G>C mutation can lead to the retainment of intron 9 as the 5?-donor splice site disappears during post-transcriptional processing of mRNA. In conclusion, our study identified three novel SCNN1A gene mutations in two Chinese patients with systemic PHA1. PMID:23762408

Yin, Lei; Li, Jing; Yu, Li; Shen, Ye; Yu, Yongguo; Shen, Yongnian; Fu, Qihua

2013-01-01

402

Analysis of TPO gene in Turkish children with iodide organification defect: identification of a novel mutation.  

PubMed

The objective was to determine molecular genetic analysis of the TPO gene in Turkish children with iodide organification defect (IOD). Patients with a diagnosis of primary hypothyroidism were evaluated. Subjects having a definite diagnosis of autoimmune thyroiditis, thyroid gland dysplasia and, or iodine deficiency were excluded. A total of 10 patients from nine unrelated Turkish families, with an unknown etiology of hypothyroidism, and with a presumptive diagnosis of IOD were included in the study. A perchlorate discharge test (PDT) was performed to all subjects, and sequence analysis of TPO gene was applied in patients with a positive PDT. Five out of 10 patients have a total IOD, while the five remaining patients have a partial IOD according to PDT results. In two sisters, one has a partial and the other one has a total IOD a novel homozygous nonsense p.Q315X mutation was found in exon 8. Additionally, a previously known homozygous missense p.R314W mutation was detected in the same exon in another patient with a total IOD. No TPO gene mutation was detected in any of the seven remaining patients. Two different TPO gene mutations were found to be responsible for IOD in two unrelated Turkish families from the same ethnic background. More subjects should be screened for detecting the prevalence and spectrum profile of TPO mutations in our population that might be helpful for understanding the pathophysiology of congenital hypothyroidism. PMID:20963560

Turkkahraman, Doga; Alper, Ozgul M; Pehlivanoglu, Suray; Aydin, Funda; Yildiz, Akin; Luleci, Guven; Akcurin, Sema; Bircan, Iffet

2010-02-01

403

Association of mutations in mannose binding protein gene with childhood infection in consecutive hospital series.  

PubMed Central

OBJECTIVE: To determine the extent to which mutations in the mannose binding protein gene predispose to childhood infection. DESIGN: Clinical details and genotype of mannose binding protein determined in consecutive children attending a paediatric department. SETTING: Inner city hospital paediatric service in London. SUBJECTS: 617 children attending hospital between October 1993 and August 1995. MAIN OUTCOME MEASURE: Infection as the cause for attendance or admission in relation to mutations in the mannose binding protein gene. RESULTS: The prevalence of mutations in the mannose binding protein gene in children with infection (146/345) was about twice that in children without infection (64/272) (P < 0.0001). Increased susceptibility to infection was found in both heterozygotic and homozygotic children. 13 out of 17 children homozygotic for variant alleles presented with strikingly severe infections, including 6 with septicaemia. CONCLUSIONS: The findings suggest that mutations in the mannose binding protein