Y-chromosome-specific microsatellite mutation rates re-examined using a minisatellite, MSY1.

Science.gov (United States)

Jobling, M A; Heyer, E; Dieltjes, P; de Knijff, P

1999-10-01

Polymorphic Y-chromosome-specific microsatellites are becoming increasingly used in evolutionary and forensic studies and, in particular, in dating the origins of Y-chromosomal lineages. Previously, haplotyping of Y chromosomes from males belonging to a set of deep-rooting pedigrees was used to estimate a conservative average Y-chromosomal microsatellite mutation rate of 2.1 x 10(-3)per locus per generation. A number of males showed multiple differences in haplotypes compared with other males within their pedigrees, and these were excluded from the calculation of this estimate, on the grounds that non-paternity was a more probable explanation than multiple mutation within a lineage. Here we reanalyse the pedigrees using an independent highly polymorphic system, the Y-specific minisatellite, MSY1. This supports the hypothesis of non-paternity where more than one microsatellite difference was observed, provides further support for the previously deduced microsatellite mutation rate and throws light on the mutation dynamics of MSY1 itself, suggesting that single-step changes are not the only mode of mutation.

Radiation-induced mutations in mammals

International Nuclear Information System (INIS)

Ehling, U.H.

1993-01-01

The aims of the proposed project are to provide a better basis for extrapolation of animal data to man. Genetic endpoint, strain and species comparisons are made, which will provide critical experimental data regarding strategies in extrapolating laboratory animal data to man. Experiments were conducted to systematically compare the spontaneous and radiation-induced mutation rates for recessive specific-locus, dominant cataract and enzyme activity alleles in the mouse as well as a comparison of the mutation rate in the mouse and hamster for dominant cataract and enzyme activity alleles. The comparison of the radiation-dose response for recessive specific-locus and dominant cataract mutations are extended. Selected mutations are characterized at the genetic, biochemical and molecular levels. (R.P.) 5 refs., 3 tabs

Cytotoxicity and genotoxicity of UVA irradiation in Chinese hamster ovary cells measured by specific locus mutations, sister chromatid exchanges and chromosome aberrations

International Nuclear Information System (INIS)

Lundgren, Karsten; Wulf, H.C.

1988-01-01

The increasing use of artificial UVA (320-400 nm) suntanning devices has brought attention to possible hazardous effects of UVA. In contrast with earlier studies, several groups recently have described that UVA possibly is mutagenic. We evaluate the genotoxic properties of broad band UVA using CHO cells and three different assays: specific locus (HGPRT) mutations, chromosome aberrations, and sister chromatid exchanges (SCEs). The UVA-source was an UVASUN 2000 S (Mutzhas), emitting UVA above 340 nm. The survival curve of the cells exhibited a shoulder up to 200 kJ/m 2 , that was followed by exponential killing at higher fluences. Mutations were induced linearly in the fluence range of 0-200 kJ/m 2 to a level seven fold higher than the spontaneous, followed by a decrease at fluences above 300 kJ/m 2 . Over the total range of tested fluences (0-300 kJ/m 2 ) a linear dose-response relationship was observed for UVA-induced SCEs. A significantly higher percentage of the cells showed chromosomes with aberrations at the higher levels of exposure (200, 300 and 400 kJ/m 2 ), but no dose response was demonstrated. Our results confirm recent findings showing that UVA is mutagenic in mammalian cells and suggest that UVA exposure may contribute to the total burden of genetic damage caused by exposure to ultraviolet light. (author)

Stage-specific hypermutability of the regA locus of Volvox, a gene regulating the germ-soma dichotomy

International Nuclear Information System (INIS)

Kirk, D.L.; Baran, G.J.; Harper, J.F.; Huskey, R.J.; Huson, K.S.; Zagris, N.

1987-01-01

Mutation at the regA locus confers on somatic cells of Volvox (which otherwise undergo programmed death) ability to redifferentiate as reproductive cells. Stable mutations at the regA locus, but not at other loci, were induced at high frequency when embryos at one particular stage were exposed to either UV irradiation, novobiocin, nalidixic acid, bleomycin, 4-hydroxyaminoquinoline-1-oxide, 5-bromodeoxyuridine, or 5-fluorouracil. All treatments led to some mutations that were not expressed until the second generation after treatment. The sensitive period was after somatic and reproductive cells of the next generation had been set apart, but before they had undergone cytodifferentiation. Hypermutability occurs in presumptive reproductive cells (in which regA is normally not expressed) somewhat before regA normally acts in somatic cells. We postulate that hypermutability of regA in the reproductive cells at this time reflects a change of state that the locus undergoes as it is inactivated

The nature of radiation-induced mutations at the white locus of Drosophila melanogaster

International Nuclear Information System (INIS)

Pastink, A.; Schalet, A.P.; Vreeken, C.; Eeken, J.C.J.; Paradi, E.

1987-01-01

X-ray- and neutron-induced mutations at the white locus of Drosophila melanogaster were used to study the nature of radiation-induced genetic damage. Genetic analysis showed the presence of multi-locus deficiencies in 15 out of 31 X-ray mutants and in 26 out of 35 mutants induced by neutrons. The DNA from 11 X-ray and 4 neutron mutants, which were not multi-locus deficiencies, was analyzed by Southern blot-hybridization. Deletions were observed in 2 X-ray and 1 neutron mutant. In combination with cytogenetic techniques, chromosomal rearrangements affecting the white locus (translocations, inversions, etc.) were identified in 3 X-ray and in 2 neutron mutants. A hot-spot for translocation breakpoints was identified in the left arm of the third chromosome. 5 X-ray mutants, which apparently did not contain large deletions, were subjected to further analysis by the nuclease S1 protection method, after cloning of the white gene. In 4 mutants a small deletion could indeed be detected in this way. Thus it seems that by far the main part of X-ray- and neutron-induced white mutants have arisen through large changes in the white gene, especially deletions. (Auth.)

Mutator activity in Schizophyllum commune

Energy Technology Data Exchange (ETDEWEB)

Shneyour, Y.; Koltin, Y. (Tel Aviv Univ. (Israel). Dept. of Microbiology)

1983-01-01

A strain with an elevated level of spontaneous mutations and an especially high rate of reversion at a specific locus (pab/sup -/) was identified. The mutator trait is recessive. UV sensitivity and the absence of a UV-specific endonucleolytic activity were associated with the enhancement of the mutation rate in mutator strains. The endonuclease associated with the regulation of the mutation rate also acted on single-stranded DNA. The molecular weight of this enzyme is about 38,000 daltons.

Locus-specific view of flax domestication history

Science.gov (United States)

Fu, Yong-Bi; Diederichsen, Axel; Allaby, Robin G

2012-01-01

Crop domestication has been inferred genetically from neutral markers and increasingly from specific domestication-associated loci. However, some crops are utilized for multiple purposes that may or may not be reflected in a single domestication-associated locus. One such example is cultivated flax (Linum usitatissimum L.), the earliest oil and fiber crop, for which domestication history remains poorly understood. Oil composition of cultivated flax and pale flax (L. bienne Mill.) indicates that the sad2 locus is a candidate domestication locus associated with increased unsaturated fatty acid production in cultivated flax. A phylogenetic analysis of the sad2 locus in 43 pale and 70 cultivated flax accessions established a complex domestication history for flax that has not been observed previously. The analysis supports an early, independent domestication of a primitive flax lineage, in which the loss of seed dispersal through capsular indehiscence was not established, but increased oil content was likely occurred. A subsequent flax domestication process occurred that probably involved multiple domestications and includes lineages that contain oil, fiber, and winter varieties. In agreement with previous studies, oil rather than fiber varieties occupy basal phylogenetic positions. The data support multiple paths of flax domestication for oil-associated traits before selection of the other domestication-associated traits of seed dispersal loss and fiber production. The sad2 locus is less revealing about the origin of winter tolerance. In this case, a single domestication-associated locus is informative about the history of domesticated forms with the associated trait while partially informative on forms less associated with the trait. PMID:22408732

Re-analysis of radiation-induced specific locus mutations in the mouse

International Nuclear Information System (INIS)

Abrahamson, S.; Wolff, S.

1976-01-01

It is stated that a re-analysis of published data on mouse mutation rates induced by x-and gamma rays suggests that the kinetics of induction can be analysed by fitting that data to a parabolic curve. This is interpreted to mean that a substantial proportion of the induced mutations results from gross chromosomal changes such as deletions, some of which are one-track and some of which are two-track. This analysis is based on the assumption that the shape of the dose curve, which in the female is concave upward, reflects the manner in which the mutations are induced rather than representing a one-track (linear) curve whose shape has been modified by differential repair. (author)

Mutations in LOXHD1, a Recessive-Deafness Locus, Cause Dominant Late-Onset Fuchs Corneal Dystrophy

Science.gov (United States)

Riazuddin, S. Amer; Parker, David S.; McGlumphy, Elyse J.; Oh, Edwin C.; Iliff, Benjamin W.; Schmedt, Thore; Jurkunas, Ula; Schleif, Robert; Katsanis, Nicholas; Gottsch, John D.

2012-01-01

Fuchs corneal dystrophy (FCD) is a genetic disorder of the corneal endothelium and is the most common cause of corneal transplantation in the United States. Previously, we mapped a late-onset FCD locus, FCD2, on chromosome 18q. Here, we present next-generation sequencing of all coding exons in the FCD2 critical interval in a multigenerational pedigree in which FCD segregates as an autosomal-dominant trait. We identified a missense change in LOXHD1, a gene causing progressive hearing loss in humans, as the sole variant capable of explaining the phenotype in this pedigree. We observed LOXHD1 mRNA in cultured human corneal endothelial cells, whereas antibody staining of both human and mouse corneas showed staining in the corneal epithelium and endothelium. Corneal sections of the original proband were stained for LOXHD1 and demonstrated a distinct increase in antibody punctate staining in the endothelium and Descemet membrane; punctate staining was absent from both normal corneas and FCD corneas negative for causal LOXHD1 mutations. Subsequent interrogation of a cohort of >200 sporadic affected individuals identified another 15 heterozygous missense mutations that were absent from >800 control chromosomes. Furthermore, in silico analyses predicted that these mutations reside on the surface of the protein and are likely to affect the protein's interface and protein-protein interactions. Finally, expression of the familial LOXHD1 mutant allele as well as two sporadic mutations in cells revealed prominent cytoplasmic aggregates reminiscent of the corneal phenotype. All together, our data implicate rare alleles in LOXHD1 in the pathogenesis of FCD and highlight how different mutations in the same locus can potentially produce diverse phenotypes. PMID:22341973

A locus-specific database for mutations in GDAP1 allows analysis of genotype-phenotype correlations in Charcot-Marie-Tooth diseases type 4A and 2K

Directory of Open Access Journals (Sweden)

Cassereau Julien

2011-12-01

Full Text Available Abstract Background The ganglioside-induced differentiation-associated protein 1 gene (GDAP1, which is involved in the Charcot-Marie-Tooth disease (CMT, the most commonly inherited peripheral neuropathy, encodes a protein anchored to the mitochondrial outer membrane. The phenotypic presentations of patients carrying GDAP1 mutations are heterogeneous, making it difficult to determine genotype-phenotype correlations, since the majority of the mutations have been found in only a few unrelated patients. Locus-specific databases (LSDB established in the framework of the Human Variome Project provide powerful tools for the investigation of such rare diseases. Methods and Results We report the development of a publicly accessible LSDB for the GDAP1 gene. The GDAP1 LSDB has adopted the Leiden Open-source Variation Database (LOVD software platform. This database, which now contains 57 unique variants reported in 179 cases of CMT, offers a detailed description of the molecular, clinical and electrophysiological data of the patients. The usefulness of the GDAP1 database is illustrated by the finding that GDAP1 mutations lead to primary axonal damage in CMT, with secondary demyelination in the more severe cases of the disease. Conclusion Findings of this nature should lead to a better understanding of the pathophysiology of CMT. Finally, the GDAP1 LSDB, which is part of the mitodyn.org portal of databases of genes incriminated in disorders involving mitochondrial dynamics and bioenergetics, should yield new insights into mitochondrial diseases.

Nature of unstable insertional mutations and reversions at the cut locus of Drosophila melanogaster: Molecular mechanism for transpositional memory

International Nuclear Information System (INIS)

Mizrokhi, L.Yu.; Georgieva, S.G.; Obolenkova, L.A.; Priimyagi, A.F.; Gerasimova, T.I.; Il'in, Yu.V.

1988-01-01

A segment of the cut locus containing an mdg4 insertion as a result of ct MR and ct MRp10 mutations was cloned. Clones were obtained for the phenotypically different ct MR2 and ct MRpN10 mutants and for stable and unstable revertants. All mutations studied are associated with mdg4 insertion at an identical nucleotide sequence of the cut locus, the same site at which mdg4 is inserted at the ct 6 allele. The ct MRpN line differs from ct MR2 in that the mobile element jockey (3 kbp) is inserted in mdg4. Jockey is represented by about 1,000 copies per genome; it is homogeneous and lacks long terminal repeats (LTRs). In stable ct + reversions, mdg4 is completely excised. In unstable ct + reversions, in which there is a high degree of reverse directed transposition of mdg4 to the cut locus, an LTR of mdg4 is preserved at the site of the mutation. It is a sequence along which new copies of mdg4 or jockey-containing mdg4 are inserted into the genome. The authors discuss a molecular mechanism for transpositional memory involving homologous recombination of the remnant LTR and circular extrachromosomal copies of mdg4

Effects of spermine on the detection of induced forward mutation at the CAN1 locus in yeast: evidence for selection against canavanine-resistant mutants

Energy Technology Data Exchange (ETDEWEB)

McDougall, K.J.; Lemontt, J.F.

1979-01-01

The effect of exogenous spermine tetrahydrochloride (0.5 mg/ml) on hydrazine- and nitrous acid-induced forward mutation to canavanine resistance (CAN1 ..-->.. can1, normal to defective arginine permease) was examined in stationary-phase haploid Saccharomyces cerevisiae. Post-treatment cell division (specifically DNA replication) is required for hydrazine mutagenesis at this locus, whereas nitrous acid mutagenesis exhibits, in addition, a significant post-treatment-independent component.

Molecular analysis of two mouse dilute locus deletion mutations: Spontaneous dilute lethal20J and radiation-induced dilute prenatal lethal Aa2 alleles

International Nuclear Information System (INIS)

Strobel, M.C.; Seperack, P.K.; Copeland, N.G.; Jenkins, N.A.

1990-01-01

The dilute (d) coat color locus of mouse chromosome 9 has been identified by more than 200 spontaneous and mutagen-induced recessive mutations. With the advent of molecular probes for this locus, the molecular lesion associated with different dilute alleles can be recognized and precisely defined. In this study, two dilute mutations, dilute-lethal20J (dl20J) and dilute prenatal lethal Aa2, have been examined. Using a dilute locus genomic probe in Southern blot analysis, we detected unique restriction fragments in dl20J and Aa2 DNA. Subsequent analysis of these fragments showed that they represented deletion breakpoint fusion fragments. DNA sequence analysis of each mutation-associated deletion breakpoint fusion fragment suggests that both genomic deletions were generated by nonhomologous recombination events. The spontaneous dl20J mutation is caused by an interstitial deletion that removes a single coding exon of the dilute gene. The correlation between this discrete deletion and the expression of all dilute-associated phenotypes in dl20J homozygotes defines the dl20J mutation as a functional null allele of the dilute gene. The radiation-induced Aa2 allele is a multilocus deletion that, by complementation analysis, affects both the dilute locus and the proximal prenatal lethal-3 (pl-3) functional unit. Molecular analysis of the Aa2 deletion breakpoint fusion fragment has provided access to a previously undefined gene proximal to d. Initial characterization of this new gene suggests that it may represent the genetically defined pl-3 functional unit

Analysis of the albino-locus region of the mouse. II. Mosaic mutants

International Nuclear Information System (INIS)

Russell, L.B.

1979-01-01

Among 119 mutations involving the c locus that were recovered in the course of mouse specific-locus experiments with external radiations, 16 were found in mosaic, or fractional, mutants. The number of additional c-locus fractionals that could have occurred in these experiments and, for a variety of reasons, might not have been clearly identified, probably does not exceed the present number. There was no evidence for radiation induction of the fractionals, and even those occurring in the irradiated groups may thus be assumed to be of spontaneous origin. Since only two mutations in the control groups were found in whole-body mutants, it appears that the bulk of spontaneous c-locus mutations are fractionals. None of the mutations recovered in fractional mutants was homozygous lethal; 25% were viable intermediate alleles, and the remainder were albino-like mutants, all viable except for one subvital and one not tested. Genetic tests of the fractionals indicated no major selection against the new mutations, either gametically or in the progeny. For the group of fractionals as a whole, about one-half of the germinal tissue carried the mutation, indicating that the fractionals came from an overall blastomere population that was one-half mutant. Such a population could result from mutation in one strand of the gamete DNA, in a daughter chromosome derived from pronuclear DNA synthesis of the zygote, or in one of the first two blastomeres prior to replication. Since the mouse embryo does not stem from all of the cleavage products of the zygote, the frequency of fractionals observeed underestimates the frequency of mutational events that result in two types of blastomeres

Somatic INK4a-ARF locus mutations: a significant mechanism of gene inactivation in squamous cell carcinomas of the head and neck.

Science.gov (United States)

Poi, M J; Yen, T; Li, J; Song, H; Lang, J C; Schuller, D E; Pearl, D K; Casto, B C; Tsai, M D; Weghorst, C M

2001-01-01

The INK4a-ARF locus is located on human chromosome 9p21 and is known to encode two functionally distinct tumor-suppressor genes. The p16(INK4a) (p16) tumor-suppressor gene product is a negative regulator of cyclin-dependent kinases 4 and 6, which in turn positively regulate progression of mammalian cells through the cell cycle. The p14(ARF) tumor-suppressor gene product specifically interacts with human double minute 2, leading to the subsequent stabilization of p53 and G(1) arrest. Previous investigations analyzing the p16 gene in squamous cell carcinomas of the head and neck (SCCHNs) have suggested the predominate inactivating events to be homozygous gene deletions and hypermethylation of the p16 promoter. Somatic mutational inactivation of p16 has been reported to be low (0-10%, with a combined incidence of 25 of 279, or 9%) and to play only a minor role in the development of SCCHN. The present study examined whether this particular mechanism of INK4a/ARF inactivation, specifically somatic mutation, has been underestimated in SCCHN by determining the mutational status of the p16 and p14(ARF) genes in 100 primary SCCHNs with the use of polymerase chain reaction technology and a highly sensitive, nonradioactive modification of single-stranded conformational polymorphism (SSCP) analysis termed "cold" SSCP. Exons 1alpha, 1beta, and 2 of INK4a/ARF were amplified using intron-based primers or a combination of intron- and exon-based primers. A total of 27 SCCHNs (27%) exhibited sequence alterations in this locus, 22 (22%) of which were somatic sequence alterations and five (5%) of which were a single polymorphism in codon 148. Of the 22 somatic alterations, 20 (91%) directly or indirectly involved exon 2, and two (9%) were located within exon 1alpha. No mutations were found in exon 1beta. All 22 somatic mutations would be expected to yield altered p16 proteins, but only 15 of them should affect p14(ARF) proteins. Specific somatic alterations included microdeletions or

Molecular analysis of radiation-induced albino (c)-locus mutations that cause death at preimplantation stages of development

International Nuclear Information System (INIS)

Rinchik, E.M.; Toenjes, R.R.; Paul, D.; Potter, M.D.

1993-01-01

Deletion mutations at the albino (c) locus have been useful for continuing the development of fine-structure physical and functional maps of the Fes-Hbb region of mouse chromosome 7. This report describes the molecular analysis of a number of radiation-induced c deletions that, when homozygous, cause death of the embryo during preimplantation stages. The distal extent of these deletions defines a locus, pid, (preimplantation development) genetically associated with this phenotype. The proximal breakpoints of eight of these deletions were mapped with respect to the Tyr (tyrosinase; albino) gene as well as to anonymous loci within the Fah-Tyr region that are defined by the Pmv-31 viral integration site and by chromosome-microdissection clones. Rearrangements corresponding to the proximal breakpoints of two of these deletions were detected by Southern blot analysis, and a size-altered restriction fragment carrying the breakpoint of one of them was cloned. A probe derived from this deletion fusion fragment defines a locus, D7Rn6, which maps within (or distal to) the pid region, and which discriminates among the distal extents of deletions eliciting the pid phenotype. Extension of physical maps from D7Rn6 should provide access both to the pid region and to loci mapping distal to pid that are defined by N-ethyl-N-nitrosourea-induced lethal mutations. 36 refs., 10 figs

HAEdb: a novel interactive, locus-specific mutation database for the C1 inhibitor gene.

Science.gov (United States)

Kalmár, Lajos; Hegedüs, Tamás; Farkas, Henriette; Nagy, Melinda; Tordai, Attila

2005-01-01

Hereditary angioneurotic edema (HAE) is an autosomal dominant disorder characterized by episodic local subcutaneous and submucosal edema and is caused by the deficiency of the activated C1 esterase inhibitor protein (C1-INH or C1INH; approved gene symbol SERPING1). Published C1-INH mutations are represented in large universal databases (e.g., OMIM, HGMD), but these databases update their data rather infrequently, they are not interactive, and they do not allow searches according to different criteria. The HAEdb, a C1-INH gene mutation database (http://hae.biomembrane.hu) was created to contribute to the following expectations: 1) help the comprehensive collection of information on genetic alterations of the C1-INH gene; 2) create a database in which data can be searched and compared according to several flexible criteria; and 3) provide additional help in new mutation identification. The website uses MySQL, an open-source, multithreaded, relational database management system. The user-friendly graphical interface was written in the PHP web programming language. The website consists of two main parts, the freely browsable search function, and the password-protected data deposition function. Mutations of the C1-INH gene are divided in two parts: gross mutations involving DNA fragments >1 kb, and micro mutations encompassing all non-gross mutations. Several attributes (e.g., affected exon, molecular consequence, family history) are collected for each mutation in a standardized form. This database may facilitate future comprehensive analyses of C1-INH mutations and also provide regular help for molecular diagnostic testing of HAE patients in different centers.

Germ-line mutations at a mouse ESTR (Pc-3) locus and human microsatellite loci

International Nuclear Information System (INIS)

Ryo, Haruko; Nakajima, Hiroo; Nomura, Taisei

2006-01-01

We examined the use of the mouse Pc-3 ESTR (expanded simple tandem repeat) locus and 72 human microsatellite loci as potentially sensitive biomarkers for mutagenic exposures to germ cells in mice and humans respectively. In the mouse work, we treated male mice with TCDD (2, 3, 7, 8-tetrachlo-rodibenzo-p-dioxin; a chemical known to induce congenital anomalies in humans and mice) and, analysed the F 1 fetuses for Pc-3 mutations. Although the incidence of anomalies was higher in the TCDD group, there were no induced mutations. However, respiratory distress syndrome (RDS) was observed in 3 of 7 fetuses born to male mice which were treated with TCDD and which showed abnormal length of Pc-3 allele. In the human studies, the children of Chernobyl liquidators were examined for mutations at a total of 72 (31 autosomal, 1 X-linked and 40 Y-linked) microsatellite loci. This study was prompted by earlier findings of increases in microsatellite mutations in barn swallows and wheat in the highly contaminated areas after the Chernobyl accident. We examined 64 liquidator families (70 children) and 66 control families (70 children). However, no increases in mutation rates were found. The estimated mean dose to the liquidators was about 39 mSv and this might be one possible reason why no increases of mutations could be found. (author)

Molecular and recombinational mapping of mutations in the Ace locus of Drosophila melanogaster

International Nuclear Information System (INIS)

Nagoshi, R.N.; Gelbart, W.M.

1987-01-01

The Ace locus in Drosophila melanogaster is known to be the structural gene for acetylcholinesterase. Ace is located in a region of chromosome arm 3R which has been subjected to intensive genetic and molecular analysis. Previous deletion mapping studies have identified a 40-kb region with which the Ace gene resides. This report focuses on the further localization of Ace within this 40-kb interval. Within this region, selective fine structure recombinational analysis was employed to localize three recessive Ace lethals relative to unselected restriction site variations. These three mutations fall into a segment of 7 kb within the Ace interval. Fine structure recombinational analysis was also used to confirm that the Ace - phenotype of one deletion, Df(3R)Ace/sup HD1/, co-segregated with the molecular deletion. This deletion does not fully remove Ace activity, but it behaves as a recessive Ace lethal. Df(3R)Ace/sup HD1/ is the most distal Ace lesion identified and indicates that the Ace locus must extend at least 16 kb. Several poly(A)transcripts are detectable in the region defined by the Ace lesions. The position and extent of the Ace locus, as well as the types of transcripts found, is consistent with the recent findings which identified Torpedo-AChE homologous cDNA sequences in this region

[Effect of estradiol on food intake, glucose and fat metabolism in mice C57BL/6J with mutation yellow at the agouti locus].

Science.gov (United States)

Iakovleva, T V; Makarova, E N; Kazantseva, A Iu; Bazhan, N M

2012-05-01

Mutation yellow at the agouti locus in mice (A(y)/a-mice) causes the increase of food intake and development of obesity and type 2 diabetes. In A(y)/a-females the disturbances of glucose and fat metabolisms occur after puberty. We have assumed that the mutation yellow violates the regulatory effect of estradiol on glucose and fat metabolism in mice. We investigated the effects of ovariectomy and estradiol treatment on body weight, food intake, glucose tolerance, plasma levels of glucose, insulin and etherified fatty acids in A(y)/a-females. C57Bl/6J females, not carrying yellow mutation at the agouti locus (a/a-mice), were used as a control. The data suggest that the yellow mutation did not affect estradiol regulation of food intake and glucose blood levels after a night of fasting, but, apparently, prevented estradiol participation in the regulation of glucose and fat metabolisms in the muscle and fat tissues.

Single locus affects embryonic segment polarity and multiple aspects of an adult evolutionary novelty

Directory of Open Access Journals (Sweden)

Saenko Suzanne V

2010-08-01

Full Text Available Abstract Background The characterization of the molecular changes that underlie the origin and diversification of morphological novelties is a key challenge in evolutionary developmental biology. The evolution of such traits is thought to rely largely on co-option of a toolkit of conserved developmental genes that typically perform multiple functions. Mutations that affect both a universal developmental process and the formation of a novelty might shed light onto the genetics of traits not represented in model systems. Here we describe three pleiotropic mutations with large effects on a novel trait, butterfly eyespots, and on a conserved stage of embryogenesis, segment polarity. Results We show that three mutations affecting eyespot size and/or colour composition in Bicyclus anynana butterflies occurred in the same locus, and that two of them are embryonic recessive lethal. Using surgical manipulations and analysis of gene expression patterns in developing wings, we demonstrate that the effects on eyespot morphology are due to changes in the epidermal response component of eyespot induction. Our analysis of morphology and of gene expression in mutant embryos shows that they have a typical segment polarity phenotype, consistent with the mutant locus encoding a negative regulator of Wingless signalling. Conclusions This study characterizes the segregation and developmental effects of alleles at a single locus that controls the morphology of a lineage-specific trait (butterfly eyespots and a conserved process (embryonic segment polarity and, specifically, the regulation of Wingless signalling. Because no gene with such function was found in the orthologous, highly syntenic genomic regions of two other lepidopterans, we hypothesize that our locus is a yet undescribed, possibly lineage-specific, negative regulator of the conserved Wnt/Wg pathway. Moreover, the fact that this locus interferes with multiple aspects of eyespot morphology and maps to a

Perspective on sequence evolution of microsatellite locus (CCGn in Rv0050 gene from Mycobacterium tuberculosis

Directory of Open Access Journals (Sweden)

Jin Ruiliang

2011-08-01

Full Text Available Abstract Background The mycobacterial genome is inclined to polymerase slippage and a high mutation rate in microsatellite regions due to high GC content and absence of a mismatch repair system. However, the exact molecular mechanisms underlying microsatellite variation have not been fully elucidated. Here, we investigated mutation events in the hyper-variable trinucleotide microsatellite locus MML0050 located in the Rv0050 gene of W-Beijing and non-W-Beijing Mycobacterium tuberculosis strains in order to gain insight into the genomic structure and activity of repeated regions. Results Size analysis indicated the presence of five alleles that differed in length by three base pairs. Moreover, nucleotide gains occurred more frequently than loses in this trinucleotide microsatellite. Mutation frequency was not completely related with the total length, though the relative frequency in the longest allele was remarkably higher than that in the shortest. Sequence analysis was able to detect seven alleles and revealed that point mutations enhanced the level of locus variation. Introduction of an interruptive motif correlated with the total allele length and genetic lineage, rather than the length of the longest stretch of perfect repeats. Finally, the level of locus variation was drastically different between the two genetic lineages. Conclusion The Rv0050 locus encodes the bifunctional penicillin-binding protein ponA1 and is essential to mycobacterial survival. Our investigations of this particularly dynamic genomic region provide insights into the overall mode of microsatellite evolution. Specifically, replication slippage was implicated in the mutational process of this microsatellite and a sequence-based genetic analysis was necessary to determine that point mutation events acted to maintain microsatellite size integrity while providing genomic diversity.

Diversity of equine major histocompatiblity complex class II DRA locus in Posavina and Croatian Coldblood horse: a new polymorphism detected

Directory of Open Access Journals (Sweden)

Ino Curik

2010-01-01

Full Text Available Domestic equidae display polymorphism within ELA-DRA locus which is not characteristic for other species. We characterised sequence polymorphism present at ELADRA locus exon 2 and estimated allele frequencies in two autochthonous breeds, Posavina and Croatian Coldblood. In 88 horses, four different alleles were found, one of them not reported before in horses. The new allele shows non-synonymous mutation at position 65 (T→A causing amino acid change (Phe→Tyr in antigen binding site and synonymous mutation at position 105 (C→T. Our findings emphasize the importance of DRA polymorphism among equids and some specific DRA frequency pattern potentially specific in draught horses.

Mutations induced by X-radiation in the yeast Schizosaccharomyces pombe

International Nuclear Information System (INIS)

Loprieno, N.; Barale, R.; Baroncelli, S.; Cammellini, A.; Melani, M.; Nieri, R.; Nozzolini, M.; Rossi, A.M.; Pisa Univ.

1975-01-01

Experiments on strains of yeast with different genetic backgrounds were done to evaluate the kinetics of inactivation and mutation induction by X-radiation. A system of forward mutation induction in five loci was used and a specific mutation rate was evaluated for the wild type. From a comparison of observations with wild type and radiation-sensitive strains, it may be assumed that in this yeast, mutations are mainly the result of a repair-active process. The range of genotypic and phenotypic influence upon the specific locus mutation rate was evaluated with appropriate biological material and experiments

Repair-resistant mutation in Neurospora

International Nuclear Information System (INIS)

Stadler, D.; Macleod, H.; Loo, M.

1987-01-01

Chronic UV treatment produces severalfold fewer mutations in Neurospora conidia than does the same total dose of acute UV. Experiments were designed to determine the conditions required for chronic UV mutagenesis. Measurement of the coincidence frequency for two independent mutations revealed the existence of a subset of cells which are mutable by chronic UV. Analysis of forward mutation at the mtr locus showed that the genetic alterations produced by chronic UV were virtually all point mutants, even though the assay system could detect alterations or deletions extending into neighboring genes. A significant fraction of the mutants produced by acute UV were multigenic deletions. The size of the dose-rate effect (acute UV mutation frequency divided by chronic UV mutation frequency) was compared for several different mutation assay systems. Forward mutations (recessive lethals and mtr) gave values ranging from four to nine. For events which were restricted to specific molecular sites (specific reversions and nonsense suppressor mutations), there was a wider range of dose-rate ratios. This suggests that chronic UV mutation may be restricted to certain molecular sequences or configurations

Defective replication initiation results in locus specific chromosome breakage and a ribosomal RNA deficiency in yeast.

Directory of Open Access Journals (Sweden)

Joseph C Sanchez

2017-10-01

Full Text Available A form of dwarfism known as Meier-Gorlin syndrome (MGS is caused by recessive mutations in one of six different genes (ORC1, ORC4, ORC6, CDC6, CDT1, and MCM5. These genes encode components of the pre-replication complex, which assembles at origins of replication prior to S phase. Also, variants in two additional replication initiation genes have joined the list of causative mutations for MGS (Geminin and CDC45. The identity of the causative MGS genetic variants strongly suggests that some aspect of replication is amiss in MGS patients; however, little evidence has been obtained regarding what aspect of chromosome replication is faulty. Since the site of one of the missense mutations in the human ORC4 alleles is conserved between humans and yeast, we sought to determine in what way this single amino acid change affects the process of chromosome replication, by introducing the comparable mutation into yeast (orc4Y232C. We find that yeast cells with the orc4Y232C allele have a prolonged S-phase, due to compromised replication initiation at the ribosomal DNA (rDNA locus located on chromosome XII. The inability to initiate replication at the rDNA locus results in chromosome breakage and a severely reduced rDNA copy number in the survivors, presumably helping to ensure complete replication of chromosome XII. Although reducing rDNA copy number may help ensure complete chromosome replication, orc4Y232C cells struggle to meet the high demand for ribosomal RNA synthesis. This finding provides additional evidence linking two essential cellular pathways-DNA replication and ribosome biogenesis.

Defective replication initiation results in locus specific chromosome breakage and a ribosomal RNA deficiency in yeast.

Science.gov (United States)

Sanchez, Joseph C; Kwan, Elizabeth X; Pohl, Thomas J; Amemiya, Haley M; Raghuraman, M K; Brewer, Bonita J

2017-10-01

A form of dwarfism known as Meier-Gorlin syndrome (MGS) is caused by recessive mutations in one of six different genes (ORC1, ORC4, ORC6, CDC6, CDT1, and MCM5). These genes encode components of the pre-replication complex, which assembles at origins of replication prior to S phase. Also, variants in two additional replication initiation genes have joined the list of causative mutations for MGS (Geminin and CDC45). The identity of the causative MGS genetic variants strongly suggests that some aspect of replication is amiss in MGS patients; however, little evidence has been obtained regarding what aspect of chromosome replication is faulty. Since the site of one of the missense mutations in the human ORC4 alleles is conserved between humans and yeast, we sought to determine in what way this single amino acid change affects the process of chromosome replication, by introducing the comparable mutation into yeast (orc4Y232C). We find that yeast cells with the orc4Y232C allele have a prolonged S-phase, due to compromised replication initiation at the ribosomal DNA (rDNA) locus located on chromosome XII. The inability to initiate replication at the rDNA locus results in chromosome breakage and a severely reduced rDNA copy number in the survivors, presumably helping to ensure complete replication of chromosome XII. Although reducing rDNA copy number may help ensure complete chromosome replication, orc4Y232C cells struggle to meet the high demand for ribosomal RNA synthesis. This finding provides additional evidence linking two essential cellular pathways-DNA replication and ribosome biogenesis.

Neutron-induced mutation experiments and total radiation-induced genetic damage in entire genomes of Drosophila melanogaster. Final report, November 1, 1967-August 31, 1980

International Nuclear Information System (INIS)

Abrahamson, S.

1981-02-01

Neutron-induced mutation experiments with Drosophila oogonia were conducted at the University of Wisconsin, with irradiations being carried out at the RARAF facility at Brookhaven National Laboratory. X-linked recessive lethals and specific locus mutations were studied. Using the α value of the weighted linear regression equation for lethal data, RBE's relative to X-rays were calculated for the energies of neutrons studied. They are: 15 MeV to 2.0; 6 MeV to 2.9; 2 MeV to 3.2; .66 MeV to 4.0; .43 MeV to 4.8. The dose/frequency response curves for lethal data of all neutron energies studied was suggestive of a quadratic component. All data best fit a linear hypothesis, however. Control data for specific locus mutations was used to estimate the number of loci on the X-chromosome which are capable of mutating to lethals. Neutron-induced data for specific locus mutation was inconclusive due to the high error inherent in the frequencies obtained

Truncating Mutations of MAGEL2, a Gene within the Prader-Willi Locus, Are Responsible for Severe Arthrogryposis

Science.gov (United States)

Mejlachowicz, Dan; Nolent, Flora; Maluenda, Jérome; Ranjatoelina-Randrianaivo, Hanitra; Giuliano, Fabienne; Gut, Ivo; Sternberg, Damien; Laquerrière, Annie; Melki, Judith

2015-01-01

Arthrogryposis multiplex congenita (AMC) is characterized by the presence of multiple joint contractures resulting from reduced or absent fetal movement. Here, we report two unrelated families affected by lethal AMC. By genetic mapping and whole-exome sequencing in a multiplex family, a heterozygous truncating MAGEL2 mutation leading to frameshift and a premature stop codon (c.1996delC, p.Gln666Serfs∗36) and inherited from the father was identified in the probands. In another family, a distinct heterozygous truncating mutation leading to frameshift (c.2118delT, p.Leu708Trpfs∗7) and occurring de novo on the paternal allele of MAGEL2 was identified in the affected individual. In both families, RNA analysis identified the mutated paternal MAGEL2 transcripts only in affected individuals. MAGEL2 is one of the paternally expressed genes within the Prader-Willi syndrome (PWS) locus. PWS is associated with, to varying extents, reduced fetal mobility, severe infantile hypotonia, childhood-onset obesity, hypogonadism, and intellectual disability. MAGEL2 mutations have been recently reported in affected individuals with features resembling PWS and called Schaaf-Yang syndrome. Here, we show that paternal MAGEL2 mutations are also responsible for lethal AMC, recapitulating the clinical spectrum of PWS and suggesting that MAGEL2 is a PWS-determining gene. PMID:26365340

Mutational specificity of SOS mutagenesis

International Nuclear Information System (INIS)

Kato, Takeshi

1986-01-01

In an approach to the isolation of mutants of E. coli unable to produce mutations by ultraviolet light, the author has found new umuC-mutants. Their properties could be explained by ''SOS hypothesis of Radman and Witkin'', which has now been justified by many investigators. Analysis of the umuC region of E. coli chromosome cloned in pSK 100 has led to the conclusion that two genes, umuD and umuC, having the capacity of mutation induction express in the same mechanism as that of SOS genes, which is known to be inhibited by LexA protein bonding to ''SOS box'' found at promotor region. Suppressor analysis for mutational specificity has revealed: (i) umuDC-independent mutagens, such as EMS and (oh) 4 Cy, induce selected base substitution alone; and (ii) umuDC-dependent mutagens, such as X-rays and gamma-rays, induce various types of base substitution simultaneously, although they have mutational specificity. In the umuDC-dependent processes of basechange mutagenesis, the spectra of base substitution were a mixture of base substitution reflecting the specific base damages induced by individual mutagens and nonspecific base substitution. In conclusion, base substitution plays the most important role in umuDC-dependent mutagenesis, although mutagenesis of umuDC proteins remains uncertain. (Namekawa, K.)

Genetic study of the PAH locus in the Iranian population: familial gene mutations and minihaplotypes.

Science.gov (United States)

Razipour, Masoumeh; Alavinejad, Elaheh; Sajedi, Seyede Zahra; Talebi, Saeed; Entezam, Mona; Mohajer, Neda; Kazemi-Sefat, Golnaz-Ensieh; Gharesouran, Jalal; Setoodeh, Aria; Mohaddes Ardebili, Seyyed Mojtaba; Keramatipour, Mohammad

2017-10-01

Phenylketonuria (PKU), one of the most common inborn errors of amino acid metabolism, is caused by mutations in the phenylalanine hydroxylase (PAH) gene (PAH). PKU has wide allelic heterogeneity, and over 600 different disease-causing mutations in PAH have been detected to date. Up to now, there have been no reports on the minihaplotype (VNTR/STR) analysis of PAH locus in the Iranian population. The aims of the present study were to determine PAH mutations and minihaplotypes in Iranian families with PAH deficiency and to investigate the correlation between them. A total of 81 Iranian families with PAH deficiency were examined using PCR-sequencing of all 13 PAH exons and their flanking intron regions to identify sequence variations. Fragment analysis of the PAH minihaplotypes was performed by capillary electrophoresis for 59 families. In our study, 33 different mutations were found accounting for 95% of the total mutant alleles. The majority of these mutations (72%) were distributed across exons 7, 11, 2 and their flanking intronic regions. Mutation c.1066-11G > A was the most common with a frequency of 20.37%. The less frequent mutations, p.Arg261Gln (8%), p.Arg243Ter (7.4%), p.Leu48Ser (7.4%), p.Lys363Asnfs*37 (6.79%), c.969 + 5G > A (6.17%), p.Pro281Leu (5.56), c.168 + 5G > C (5.56), and p.Arg261Ter (4.94) together comprised about 52% of all mutant alleles. In this study, a total of seventeen PAH gene minihaplotypes were detected, six of which associated exclusively with particular mutations. Our findings indicate a broad PAH mutation spectrum in the Iranian population, which is consistent with previous studies reporting a wide range of PAH mutations, most likely due to ethnic heterogeneity. High prevalence of c.1066-11G > A mutation linked to minihaplotype 7/250 among both Iranian and Mediterranean populations is indicative of historical and geographical links between them. Also, strong association between particular mutations and minihaplotypes

Gene mutation, quantitative mutagenesis, and mutagen screening in mammalian cells: study with the CHO/HGPRT system

International Nuclear Information System (INIS)

Hsie, A.W.

1980-01-01

We have employed CHO cells to develop and define a set of stringent conditions for studying mutation induction to TG resistance. Several lines of evidence support the CHO/HGPRT system as a specific-locus mutational assay. The system permits quantification of mutation at the HGPRT locus induced by various physical and chemical mutagens. The quantitative nature of the system provides a basis for the study of structure-function relationships of various classes of chemical mutagens. The intra- and interlaboratory reproducibility of this system suggests its potential for screening environmental agents for mutagenic activity

Mutations in the Plasmodium falciparum Cyclic Amine Resistance Locus (PfCARL Confer Multidrug Resistance

Directory of Open Access Journals (Sweden)

Gregory LaMonte

2016-07-01

Full Text Available Mutations in the Plasmodium falciparum cyclic amine resistance locus (PfCARL are associated with parasite resistance to the imidazolopiperazines, a potent class of novel antimalarial compounds that display both prophylactic and transmission-blocking activity, in addition to activity against blood-stage parasites. Here, we show that pfcarl encodes a protein, with a predicted molecular weight of 153 kDa, that localizes to the cis-Golgi apparatus of the parasite in both asexual and sexual blood stages. Utilizing clustered regularly interspaced short palindromic repeat (CRISPR-mediated gene introduction of 5 variants (L830V, S1076N/I, V1103L, and I1139K, we demonstrate that mutations in pfcarl are sufficient to generate resistance against the imidazolopiperazines in both asexual and sexual blood-stage parasites. We further determined that the mutant PfCARL protein confers resistance to several structurally unrelated compounds. These data suggest that PfCARL modulates the levels of small-molecule inhibitors that affect Golgi-related processes, such as protein sorting or membrane trafficking, and is therefore an important mechanism of resistance in malaria parasites.

Neutron-induced mutation experiments. Comprehensive report, March 1, 1977-August 31, 1980

International Nuclear Information System (INIS)

Abrahamson, S.

1981-02-01

Neutron-induced X-linked lethal mutations were induced in Drosophila melanogaster oogonia at energies of .43, .66, 2, and 6 MeV. The 37 irradiations were carried out at the RARAF facility at Brookhaven National Laboratory. RBE's (relative to x-ray data similarly collected) were calculated to be .43 MeV to 4.8; .66 MeV to 4.0; 2 MeV to 3.2; and 6 MeV to 2.9. The dose/frequency response curves for all energies best fit a linear rather than a linear-quadratic model following regression analyses. Control data for specific locus mutations (420,000 tests) were gathered. This data, combined with other data (both X-linked lethal and specific locus) has been used to estimate the number of loci on the X-chromosome of Drosophila which can mutate to recessive lethals

Relationship between healthy lifestyle behaviors and health locus of control and health-specific self-efficacy in university students.

Science.gov (United States)

Açıkgöz Çepni, Serap; Kitiş, Yeter

2017-07-01

To investigate the relationship between the healthy lifestyle behaviors and the health locus of control and health-specific self-efficacy in university students. The study included 572 undergraduate students of a university in the central Anatolia region of Turkey. The data were collected with the General Characteristics Form, the Health-Promoting Lifestyle Profile II, the Multidimensional Health Locus of Control Scale, and the Perceived Health Competence Scale and investigated with the structural equation model. Health-specific self-efficacy was an important predictor of healthy lifestyle behaviors. The Internal health locus of control influenced the healthy lifestyle behaviors through health-specific self-efficacy. The other dimension was the Powerful Others health locus of control that affected healthy lifestyle behaviors, both directly and indirectly, through health-specific self-efficacy. There was a chance that the health locus of control had a negative effect on healthy lifestyle behaviors through self-efficacy. Health-specific self-efficacy is an important prerequisite for changes in healthy lifestyle behaviors, which supports Pender's model. The subscales of the health locus of control vary in their effects on healthy lifestyle behaviors, which partly supports Pender's model. Nurses, by using this model, can examine ways of improving these cognitive-perceptual factors and implement health education programs that are directed towards improving them in young persons. © 2016 Japan Academy of Nursing Science.

High specificity but low sensitivity of mutation-specific antibodies against EGFR mutations in non-small-cell lung cancer

DEFF Research Database (Denmark)

Bondgaard, Anna-Louise; Høgdall, Estrid; Mellemgaard, Anders

2014-01-01

of more sensitive methods including real-time PCR (RT-PCR). Immunohistochemistry with mutation-specific antibodies might be a promising detection method. We evaluated 210 samples with NSCLC from an unselected Caucasian population. Extracted DNA was analyzed for EGFR mutations by RT-PCR (Therascreen EGFR......, and staining score (multipum of intensity (graded 0-3) and percentages (0-100%) of stained tumor cells) was calculated. Positivity was defined as staining score >0. Specificity of exon19 antibody was 98.8% (95% confidence interval=95.9-99.9%) and of exon21 antibody 97.8% (95% confidence interval=94...... was demonstrated. However, sensitivity was low, especially for exon19 deletions, and thus these antibodies cannot yet be used as screening method for EGFR mutations in NSCLC. Refinement of sensitivity for the mutation-specific antibodies is warranted to improve molecular diagnosis using EGFR immunohistochemistry....

Analysis of mutation/rearrangement frequencies and methylation patterns at a given DNA locus using restriction fragment length polymorphism.

Science.gov (United States)

Boyko, Alex; Kovalchuk, Igor

2010-01-01

Restriction fragment length polymorphism (RFLP) is a difference in DNA sequences of organisms belonging to the same species. RFLPs are typically detected as DNA fragments of different lengths after digestion with various restriction endonucleases. The comparison of RFLPs allows investigators to analyze the frequency of occurrence of mutations, such as point mutations, deletions, insertions, and gross chromosomal rearrangements, in the progeny of stressed plants. The assay involves restriction enzyme digestion of DNA followed by hybridization of digested DNA using a radioactively or enzymatically labeled probe. Since DNA can be digested with methylation sensitive enzymes, the assay can also be used to analyze a methylation pattern of a particular locus. Here, we describe RFLP analysis using methylation-insensitive and methylation-sensitive enzymes.

Mutation Rates of STR Systems in Danes

DEFF Research Database (Denmark)

Andersen, Kim Emil; Bøttcher, Susanne Gammelgaard; Christensen, Susanne

Danish paternity cases in the period 1999 to 2005 were investigated regarding mutation rates in STR loci. STR-typing was performed by the Applied Biosystems AmplfStr Profiler Plus kit in the period 1999 to early 2005, hereafter named the PP9, and by Applied Biosystems AmplfStr Identifier kit for ...... and kits. Sex and STR locus specific mutation rates were estimated with 95% confidence limits by the method of Clopper and Pearson (1934)....

Influence of preirradiation history of E. coli WP2 cells on the residual fixation of mutations in rpsL. (strA) locus

Energy Technology Data Exchange (ETDEWEB)

Filippov, V D

1986-07-01

The values of residual fixation of strA mutations in E.coli culture, irradiated by UV-light (6.8 J/m/sup 2/) in different physiological states and conforming to different in depth strA mutation frequency decrease in postirradiation incubation under conditions unfavourable for protein synthesis are determined. By residual fixation one should mean accumulation of strA mutations stable to antimutagenous effect of photoreactivating light in cell population incubated in buffer after UV radiation. It is established that residual fixation is small in cultures, conforming to deep decrease, and is a factor (about 40% of strA mutations is fixed) in a culture, conforming to moderate decrease (about 60% of strA mutations disappears) of mutation frequency in incubation under conditions unfavourable for protein synthesis. The conclusion is made that the depth of strA mutation frequency decrease, taking place under the influence of mfd system, depends on the level of residual fixation of this mutations. It is supposed that residual fixation is caused by rpsL (strA) locus introduction in replication cycle initiated after radiation.

Impact of loss-of-function mutations at the RNF43 locus on colorectal cancer development and progression.

Science.gov (United States)

Eto, Tsugio; Miyake, Keisuke; Nosho, Katsuhiko; Ohmuraya, Masaki; Imamura, Yu; Arima, Kota; Kanno, Shinichi; Fu, Lingfeng; Kiyozumi, Yuki; Izumi, Daisuke; Sugihara, Hidetaka; Hiyoshi, Yukiharu; Miyamoto, Yuji; Sawayama, Hiroshi; Iwatsuki, Masaaki; Baba, Yoshifumi; Yoshida, Naoya; Furukawa, Toru; Araki, Kimi; Baba, Hideo; Ishimoto, Takatsugu

2018-05-13

RNF43 mutations are frequently detected in colorectal cancer cells and lead to a loss of function of the ubiquitin E3 ligase. Here, we investigated the clinical significance of RNF43 mutations in a large Japanese cohort and the role of RNF43 at various stages of colorectal cancer development and progression. Mutation analysis of the RNF43 gene locus using pyrosequencing technology detected RNF43 hotspot mutations in 1 (0.88%) of 113 colorectal polyp cases and 30 (6.45%) of 465 colorectal cancer cases. Moreover, patients with colorectal cancer harboring mutated RNF43 experienced a higher recurrence rate than those harboring non-mutated RNF43. In addition, the growth of RNF43 wild-type colorectal cancer cell lines was significantly increased by RNF43 silencing. We generated Rnf43 knock-out mice in a C57BL/6N background using the CRISPR-Cas9 system. Although intestinal organoids from the Rnf43 knock-out mice did not show continuous growth compared with those from the wild-type mice in the absence of R-spondin, an azoxymethane (AOM)/dextran sodium sulfate (DSS) mouse model demonstrated that the tumors were markedly larger in the Rnf43 knock-out mice than in the wild-type mice. These findings provide evidence that Wnt signaling activation by RNF43 mutations during the tumorigenic stage enhances tumor growth and promotes a high recurrence rate in colorectal cancer patients. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

N-ethyl-N-nitrosourea-induced null mutation at the mouse Car-2 locus: An animal model for human carbonic anhydrase II deficiency syndrome

International Nuclear Information System (INIS)

Lewis, S.E.; Barnett, L.B.; Erickson, R.P.; Venta, P.J.; Tashian, R.E.

1988-01-01

Electrophoretic screening of (C57BL/6J x DBA/2J)F 1 progeny of male mice treated with N-ethyl-N-nitrosourea revealed a mouse that lacked the paternal carbonic anhydrase II (Ca II). Breeding tests showed that this trait was heritable and due to a null mutation at the Car-2 locus on chromosome 3. Like humans with the same inherited enzyme defect, animals homozygous for the new null allele are runted and have renal tubular acidosis. However, the prominent osteopetrosis found in humans with CA II deficiency could be detected even in very old homozygous null mice. A molecular analysis of the deficient mice shows that the mutant gene is not deleted and is transcribed. The CA II protein, which is normally expressed in most tissues, could not be detected by immunodiffusion analysis in any tissues of the CA II-deficient mice, suggesting a nonsense or a missense mutation at the Car-2 locus

Estimating spontaneous mutation rates at enzyme loci in Drosophila melanogaster

International Nuclear Information System (INIS)

Mukai, Terumi; Yamazaki, Tsuneyuki; Harada, Ko; Kusakabe, Shin-ichi

1990-04-01

Spontaneous mutations were accumulated for 1,620,826 allele-generations on chromosomes that originated from six stem second chromosomes of Drosophila melanogaster. Only null-electromorph mutations were detected. Band-electromorph mutations were not found. The average rate of null-electromorph mutations was 2.71 x 10 -5 per locus per generation. The 95% confidence interval (μ n ) was 1.97 x 10 -5 n -5 per locus per generation. The upper 95% confidence limit of the band-electromorph mutation rate (μ B ) was 2.28 x 10 -6 per locus per generation. It appeared that null mutations were induced by movable genetic elements and that the mutation rates were different from chromosome to chromosome. (author)

New mutations and an updated database for the patched-1 (PTCH1) gene.

Science.gov (United States)

Reinders, Marie G; van Hout, Antonius F; Cosgun, Betûl; Paulussen, Aimée D; Leter, Edward M; Steijlen, Peter M; Mosterd, Klara; van Geel, Michel; Gille, Johan J

2018-05-01

Basal cell nevus syndrome (BCNS) is an autosomal dominant disorder characterized by multiple basal cell carcinomas (BCCs), maxillary keratocysts, and cerebral calcifications. BCNS most commonly is caused by a germline mutation in the patched-1 (PTCH1) gene. PTCH1 mutations are also described in patients with holoprosencephaly. We have established a locus-specific database for the PTCH1 gene using the Leiden Open Variation Database (LOVD). We included 117 new PTCH1 variations, in addition to 331 previously published unique PTCH1 mutations. These new mutations were found in 141 patients who had a positive PTCH1 mutation analysis in either the VU University Medical Centre (VUMC) or Maastricht University Medical Centre (MUMC) between 1995 and 2015. The database contains 331 previously published unique PTCH1 mutations and 117 new PTCH1 variations. We have established a locus-specific database for the PTCH1 gene using the Leiden Open Variation Database (LOVD). The database provides an open collection for both clinicians and researchers and is accessible online at http://www.lovd.nl/PTCH1. © 2018 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.

Identification of a fourth locus (EVR4) for familial exudative vitreoretinopathy (FEVR).

Science.gov (United States)

Toomes, Carmel; Downey, Louise M; Bottomley, Helen M; Scott, Sheila; Woodruff, Geoffrey; Trembath, Richard C; Inglehearn, Chris F

2004-01-15

Familial exudative vitreoretinopathy (FEVR) is a genetically heterogeneous inherited blinding disorder of the retinal vascular system. To date three loci have been mapped: EVR1 on chromosome 11q, EVR2 on chromosome Xp, and EVR3 on chromosome 11p. The gene underlying EVR3 remains unidentified whilst the EVR2 gene, which encodes the Norrie disease protein (NDP), was identified over a decade ago. More recently, FZD4, the gene that encodes the Wnt receptor Frizzled-4, was identified as the mutated gene at the EVR1 locus. The purpose of this study was to screen FZD4 in a large family previously proven to be linked to the EVR1 locus. PCR products were generated using genomic DNA from affected family members with primers designed to amplify the coding sequence of FZD4. The PCR products were screened for mutations by direct sequencing. Genotyping was performed in all available family members using fluorescently labeled microsatellite markers from chromosome 11q. Sequencing of the EVR1 gene, FZD4, in this family identified no mutation. To investigate this family further we performed high-resolution genotyping with markers spanning chromosome 11q. Haplotype analysis excluded FZD4 as the mutated gene in this family and identified a candidate region approximately 10 cM centromeric to EVR1. This new FEVR locus is flanked by markers D11S1368 (centromeric) and D11S937 (telomeric) and spans approximately 15 cM. High-resolution genotyping and haplotype analysis excluded FZD4 as the defective gene in a family previously linked to the EVR1 locus. The results indicate that the gene mutated in this family lies centromeric to the EVR1 gene, FZD4, and is also genetically distinct from the EVR3 locus. This new locus has been designated EVR4 and is the fourth FEVR locus to be described.

The influence of preirradiation history of E. coli WP2 cells on the residual fixation of mutations in rpsL. (strA) locus

International Nuclear Information System (INIS)

Filippov, V.D.

1986-01-01

The values of residual fixation of strA mutations in E.coli culture, irradiated by UV-light (6.8 J/m 2 ) in different physiological states and conforming to different in depth strA mutation frequency decrease in postirradiation incubation under conditions unfavourable for protein synthesis are determined. By residual fixation one should mean accumulation of strA mutations stable to antimutagenous effect of photoreactivating light in cell population incubated in buffer after UV radiation. It is established that residual fixation is small in cultures, conforming to deep decrease, and is a factor (about 40% of strA mutations is fixed) in a culture, conforming to moderate decrease (about 60% of strA mutations disappears) of mutation frequency in incubation under conditions unfavourable for protein synthesis. The conclusion is made that the depth of strA mutation frequency decrease, taking place under the influence of mfd system, depends on the level of residual fixation of this mutations. It is supposed that residual fixation is caused by rpsL (strA) locus introduction in replication cycle initiated after radiation

Comparison of somatic mutation frequencies at HGPRT locus induced by radiation and chemical pollutant from energy system

International Nuclear Information System (INIS)

Xu Honglan; Cao Yi; Duan Zhikai; Wu Qiqing; Chen Ying; Zhang Shuxian

1998-12-01

The somatic induction frequencies of mutation at the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus induced by 60 Co γ-rays and Benzo-a-pyrene (B(a)P), which are representative of hazardous emission and pollutant from nuclear energy cycle and fossil-fuelled energy cycle respectively, were detected by using forward mutation assay and cloning technique in both V 79 Chinese hamster cells and human peripheral blood T-lymphocytes. Resistant mutants were selected with 6-thioguanine (6-TG). Dose-response curves and mathematical expressions were obtained for mutation frequencies and survival following γ-ray and B(a)P(+S 9 ) treatments. The dose ranges for the two mutagens were compared when they induced the same mutation frequencies. In V 79 /HGPRT assay system, when the mutation frequencies were 5∼35 mutants/10 6 cells the response of γ-rays in the dose range from 0.93∼4.96 Gy at dose rate of 1.16 Gy/min is nearly equivalent to that in the B(a)P dose range from 0.52∼4.27 μg/ml. By using cloning technique in T-lymphocytes, when the mutation frequencies were 1∼14 mutants/10 5 cells the response of γ-rays in the dose range from 0.05∼4.77 Gy at dose rate of 1.03 Gy/min is nearly equivalent to that in the B(a)P dose range from 0.15∼7.36 μg/ml. When the survival fraction is 37%, the mutation frequency induced by B(a)P is higher than that induced by 60 Co γ-rays

Molecular analysis of radiation-induced mutations in vitro

International Nuclear Information System (INIS)

Kronenberg, A.

1996-01-01

This review will focus on the nature of specific locus mutations detected in mammalian cells exposed in vitro to different types of ionizing radiations. Ionizing radiation has been shown to produce a wide variety of heritable alterations in DNA. These range from single base pair substitutions to stable loss or translocation of large portions of whole chromosomes. Data will be reviewed for certain test systems that reveal different mutation spectra. Techniques for the analysis of molecular alterations include applications of the polymerase chain reaction, some of which may be coupled with DNA sequence analysis, and a variety of hybridization-based techniques. The complexity of large scale rearrangements is approached with cytogenetic techniques including high resolution banding and various applications of the fluorescence in situ hybridization (FISH) technique. Radiation-induced mutant frequencies and mutation spectra are a function of the linkage constraints on the recovery of viable mutants for a given locus and test system. 44 refs

Elevated mutation rate during meiosis in Saccharomyces cerevisiae.

Science.gov (United States)

Rattray, Alison; Santoyo, Gustavo; Shafer, Brenda; Strathern, Jeffrey N

2015-01-01

Mutations accumulate during all stages of growth, but only germ line mutations contribute to evolution. While meiosis contributes to evolution by reassortment of parental alleles, we show here that the process itself is inherently mutagenic. We have previously shown that the DNA synthesis associated with repair of a double-strand break is about 1000-fold less accurate than S-phase synthesis. Since the process of meiosis involves many programmed DSBs, we reasoned that this repair might also be mutagenic. Indeed, in the early 1960's Magni and Von Borstel observed elevated reversion of recessive alleles during meiosis, and found that the revertants were more likely to be associated with a crossover than non-revertants, a process that they called "the meiotic effect." Here we use a forward mutation reporter (CAN1 HIS3) placed at either a meiotic recombination coldspot or hotspot near the MAT locus on Chromosome III. We find that the increased mutation rate at CAN1 (6 to 21 -fold) correlates with the underlying recombination rate at the locus. Importantly, we show that the elevated mutation rate is fully dependent upon Spo11, the protein that introduces the meiosis specific DSBs. To examine associated recombination we selected for random spores with or without a mutation in CAN1. We find that the mutations isolated this way show an increased association with recombination (crossovers, loss of crossover interference and/or increased gene conversion tracts). Polζ appears to contribute about half of the mutations induced during meiosis, but is not the only source of mutations for the meiotic effect. We see no difference in either the spectrum or distribution of mutations between mitosis and meiosis. The correlation of hotspots with elevated mutagenesis provides a mechanism for organisms to control evolution rates in a gene specific manner.

Mutational specificity of γ-rays

International Nuclear Information System (INIS)

Hoebee, Barbara.

1990-01-01

The aim of the study described in this thesis was to get more information on the mutagenic properties of radiation-induced DNA modifications and the possible mechanisms involved in radiation-induced mutagenesis, principally by investigating the kinds of mutations by DNA sequence analysis. The mutations were analyzed after γ-irradiation of recombinant bacteriophage M13 and plasmide pUC DNA in diluted aqueous solutions, followed by transfection or transformation to E. coli cells, in which the damaged DNA molecules are repaired and replicated. Error-prone repair, misrepair or bypass of lesions during replication may lead to the introduction of mutations. Both the M13 and the plasmid DNA used in our mutation studies contain a mutation target sequence, which makes an easy selection and sequence analysis of mutant DNA molecules possible. Under the radiation conditions used, e.g. irradiation of diluted aqueous DNA solutions, only DNA damage occurs introduced by the water derived OH* and H* radicals and the hydrated electrons. By using different gas conditions during irradiation the relative yields of these reaction species can be manipulated, which opens up the opportunity to determine their effects separately. The mutation spectrum obtained in double-stranded (ds) M13DNA after irradiation under oxic conditions and the mutation spectrum obtained under the same conditions and in the same mutation target but cloned in plasmid DNA, are described. The mutation specificity under anoxic conditions in ds M13DNA is given. Results obtained after irradiation of ds M13DNA under N 2 conditions are discussed together with experiments with single-stranded DNA. Similarities and differences between radiation-induced mutation spectra obtained by other groups and those presented in this thesis are discussed. (author). 155 refs.; 134 figs.; 16 tabs

Diversity of Pol IV function is defined by mutations at the maize rmr7 locus.

Directory of Open Access Journals (Sweden)

Jennifer L Stonaker

2009-11-01

Full Text Available Mutations affecting the heritable maintenance of epigenetic states in maize identify multiple small RNA biogenesis factors including NRPD1, the largest subunit of the presumed maize Pol IV holoenzyme. Here we show that mutations defining the required to maintain repression7 locus identify a second RNA polymerase subunit related to Arabidopsis NRPD2a, the sole second largest subunit shared between Arabidopsis Pol IV and Pol V. A phylogenetic analysis shows that, in contrast to representative eudicots, grasses have retained duplicate loci capable of producing functional NRPD2-like proteins, which is indicative of increased RNA polymerase diversity in grasses relative to eudicots. Together with comparisons of rmr7 mutant plant phenotypes and their effects on the maintenance of epigenetic states with parallel analyses of NRPD1 defects, our results imply that maize utilizes multiple functional NRPD2-like proteins. Despite the observation that RMR7/NRPD2, like NRPD1, is required for the accumulation of most siRNAs, our data indicate that different Pol IV isoforms play distinct roles in the maintenance of meiotically-heritable epigenetic information in the grasses.

Neutron-induced mutation experiments. Progress report, March 1, 1975--February 29, 1976

International Nuclear Information System (INIS)

Abrahamson, S.

1975-11-01

The relative mutagenic effectiveness of neutrons of different energies were compared with x radiation in mice and Drosophila oogonia employing X-linked recessive lethal and specific locus mutation tests. The energies and doses used were 0.68 MeV, 2 MeV, and 6 MeV (250 and 500 0 R), and 15 MeV (250, 500, and 1000 0 R). The data thus far collected from the recessive lethal test indicate that 0.68 MeV neutrons have the highest RBE among the energies tested, followed by 6 and 2 MeV. The specific locus mutation data also indicate the highest RBE for 0.68 MeV, followed respectively by 2 and 6 MeV. The 15 MeV data is as of now incompletely analyzed, as are some dose points of 2 and 6 MeV

Mutation in PLK4, encoding a master regulator of centriole formation, defines a novel locus for primordial dwarfism.

Science.gov (United States)

Shaheen, Ranad; Al Tala, Saeed; Almoisheer, Agaadir; Alkuraya, Fowzan S

2014-12-01

Primordial dwarfism (PD) is a heterogeneous clinical entity characterised by severe prenatal and postnatal growth deficiency. Despite the recent wave of disease gene discovery, the causal mutations in many PD patients remain unknown. To describe a PD family that maps to a novel locus. Clinical, imaging and laboratory phenotyping of a new family with PD followed by autozygosity mapping, linkage analysis and candidate gene sequencing. We describe a multiplex consanguineous Saudi family in which two full siblings and one half-sibling presented with classical features of Seckel syndrome in addition to optic nerve hypoplasia. We were able to map the phenotype to a single novel locus on 4q25-q28.2, in which we identified a five base-pair deletion in PLK4, which encodes a master regulator of centriole duplication. Our discovery further confirms the role of genes involved in centriole biology in the pathogenesis of PD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The mutational spectrum in Treacher Collins syndrome reveals a predominance of mutations that create a premature-termination codon

Energy Technology Data Exchange (ETDEWEB)

Edwards, S.J.; Gladwin, A.J.; Dixon, M.J. [Univ. of Manchester (United Kingdom)

1997-03-01

Treacher Collins syndrome (TCS) is an autosomal dominant disorder of craniofacial development, the features of which include conductive hearing loss and cleft palate. The TCS locus has been mapped to human chromosome 5q31.3-32 and the mutated gene identified. In the current investigation, 25 previously undescribed mutations, which are spread throughout the gene, are presented. This brings the total reported to date to 35, which represents a detection rate of 60%. Of the mutations that have been reported to date, all but one result in the introduction of a premature-termination codon into the predicted protein, treacle. Moreover, the mutations are largely family specific, although a common 5-bp deletion in exon 24 (seven different families) and a recurrent splicing mutation in intron 3 (two different families) have been identified. This mutational spectrum supports the hypothesis that TCS results from haploin-sufficiency. 49 refs., 4 figs., 3 tabs.

Enzyme-activity mutations detected in mice after paternal fractionated irradiation

International Nuclear Information System (INIS)

Charles, D.J.; Pretsch, W.

1986-01-01

(101/E1 X C3H/E1)F 1 -hybrid male mice were exposed in a 24-h fractionation interval to either 3.0 + 3.0-Gy or 5.1 + 5.1-Gy X-irradiation, and mated to untreated Test-stock females. The offspring were examined for mutations at 7 recessive specific loci and for activity alterations of erythrocyte enzymes controlled presumably by 12 loci. No enzyme-activity mutant was found in 3610 F 1 -offspring of the control group. In the experimental groups, no mutant was detected in 533 (3.0 + 3.0 Gy) and 173 (5.1 + 5.1 Gy) offspring from postspermatogonial germ cells treated. After treatment of spermatogonia, 1 mutant in 3388 F 1 -offspring of the 3.0 + 3.0-Gy group, and 5 mutants in 3187 F 1 offspring of the 5.1 + 5.1-Gy group were found. The mutants were all genetically confirmed. The frequency (expressed as mutants/locus/gamete) of enzyme-activity mutations is 2 (5.1 + 5.1-Gy group) to 10 (3.0 + 3.0-Gy group) times lower than the frequency of recessive specific-locus mutations. (Auth.)

Mutation update for the PORCN gene

DEFF Research Database (Denmark)

Lombardi, Maria Paola; Bulk, Saskia; Celli, Jacopo

2011-01-01

Mutations in the PORCN gene were first identified in Goltz-Gorlin syndrome patients in 2007. Since then, several reports have been published describing a large variety of genetic defects resulting in the Goltz-Gorlin syndrome, and mutations or deletions were also reported in angioma serpiginosum......, the pentalogy of Cantrell and Limb-Body Wall Complex. Here we present a review of the published mutations in the PORCN gene to date and report on seven new mutations together with the corresponding clinical data. Based on the review we have created a Web-based locus-specific database that lists all identified...... variants and allows the inclusion of future reports. The database is based on the Leiden Open (source) Variation Database (LOVD) software, and is accessible online at http://www.lovd.nl/porcn. At present, the database contains 106 variants, representing 68 different mutations, scattered along the whole...

High-throughput development of genome-wide locus-specific informative SSR markers in wheat

Science.gov (United States)

Although simple sequence repeat (SSR) markers are not new, they are still useful and often used markers in molecular mapping and marker-assisted breeding, particularly in developing countries. However, locus-specific SSR markers could be more useful and informative in wheat breeding and genetic stud...

Analysis of APC mutation in human ameloblastoma and clinical significance.

Science.gov (United States)

Li, Ning; Liu, Bing; Sui, Chengguang; Jiang, Youhong

2016-01-01

As a highly conserved signaling pathway, Wnt/β-catenin signal transduction pathway plays an important role in many processes. Either in the occurrence or development of tumor, activation of this pathway takes an important place. APC inhibits Wnt/β-catenin pathway to regulate cell proliferation and differentiation. This study aimed to investigate the function of cancer suppressor gene. PCR amplification and sequencing method was used to analyze APC mutations of human clinical specimens. The pathological specimens were collected for PCR and clear electrophoretic bands were obtained after electrophoresis. The gene sequence obtained after purification and sequencing analysis was compared with the known APC gene sequence (NM_000038.5). Base mutations at APC 1543 (T → C), APC-4564 (G → A), APC-5353 (T → G), APC-5550 (T → A) and APC-5969 (G → A) locus existed in 22 (27.5 %), 12 (15 %), 5 (6.25 %), 13 (16.25 %) and 12 patients (15 %), respectively. Gene mutations existed in ameloblastoma, and the mutation loci were 1543 locus (T → C), 4564 locus (G → A), 5353 locus (T → G), 5550 locus (T → A) and 5969 locus (G → A) 15 %, respectively. APC mutation plays a certain role in monitoring the tumor malignant degree as it may indicate the transition process of ameloblastoma malignant phenotype.

Genetic Linkage Analysis of DFNB2 Locus with Autosomal Recessive Hearing Loss in Families Negative for GJB2 Mutations in Khuzestan Province

Directory of Open Access Journals (Sweden)

Parisa Tahmasebi

2016-09-01

Full Text Available Abstract Background: Hearing loss is a common sensory impairment in humans which half of its causes are genetic reasons. Genetic hearing loss can be divided into the two types of syndromic and non-syndromic, which 80% of non-syndromic cases is Autosomal Recessive Non-Syndromic Hearing Loss. The aim of the present research is to determine the contribution of DFNB2 locus (MYO7A gene in causing an autosomal recessive hearing loss in the one group of the deaf families of Khuzestan province. Materials and Methods: This study was conducted on 26 families with autosomal recessive hearing loss (with 4 patients and negative for GJB2 mutations in Khuzestan province. 22 families suffered from ARNSHL and 4 families suffered from Usher syndrome. Linkage analysis was performed by using STR (Short Tandem Repeat markers related to DFNB2 locus. Each family’s genotype was determined by PCR-PAGE method. Furthermore, haplotypes drawing and LOD score calculations were performed. Results: From 26 families with hearing loss participating in this research, following genetic linkage analysis and haplotypes drawing, two families (7.7% of the families showed linkage to DFNB2 locus. One family (4.5% suffered from ARNSHL and another family suffered from Usher syndrome. Conclusion: The results of the present research show that the contribution of DFNB2 locus in causing hearing loss in the population of Khuzestan province was similar to other studies conducted in Iran and this locus with other important loci should be considered to check in the hearing loss panel.

Biochemical mutations in the children of atomic bomb survivors

International Nuclear Information System (INIS)

Satoh, Chiyoko; Neel, J.V.

1988-01-01

Genetic effects of atomic bombs in children of survivors in Hiroshima and Nagasaki were studied using two biochemical indicators. Eligible children were classified as those born to parents exposed at up to 2,000 m from the hypocenter (Group I, n=13,052); and those born to either parents exposed at a distance of over 2,500 m or parents who were not in the cities (Group II, n=10,609). Thirty blood proteins were examined by one-dimensional gel electrophoresis. In Group I, 3 mutations altering electrophoretic mobility of proteins were identified among 667,404 locus tests. This corresponded to a mutation rate of 0.45 x 10 -5 per locus per generation. In Group II, 3 mutations among 466,881 locus tests were seen, yielding a mutation rate for electromorphs of 0.64 x 10 -5 per locus per generation. According to the dose schedule developed in 1965 (T65 DR), average gonal doses of gamma and neutrons were 16.9 and 3.4, respectively, for Hiroshima's fathers; 14.0 and 1.3 for Hiroshima's mothers; 26.2 and 0.3 for Nagasaki's fathers; and 19.7 and 0.1 for Nagasaki's mothers. A screening for variants in 9 erythrocyte enzymes with activity ≤66% of normal value revealed one mutation resulting in the loss of enzyme activity in 60,529 tests for Group I, but none of the mutations in 61,741 tests for Group II. The mutation rates in both groups are thus considered to be 0.60 and 0.64 x 10 -5 , respectively, per locus per generation. (Namekawa, K)

A natural mutation-led truncation in one of the two aluminum-activated malate transporter-like genes at the Ma locus is associated with low fruit acidity in apple.

Science.gov (United States)

Bai, Yang; Dougherty, Laura; Li, Mingjun; Fazio, Gennaro; Cheng, Lailiang; Xu, Kenong

2012-08-01

Acidity levels greatly affect the taste and flavor of fruit, and consequently its market value. In mature apple fruit, malic acid is the predominant organic acid. Several studies have confirmed that the major quantitative trait locus Ma largely controls the variation of fruit acidity levels. The Ma locus has recently been defined in a region of 150 kb that contains 44 predicted genes on chromosome 16 in the Golden Delicious genome. In this study, we identified two aluminum-activated malate transporter-like genes, designated Ma1 and Ma2, as strong candidates of Ma by narrowing down the Ma locus to 65-82 kb containing 12-19 predicted genes depending on the haplotypes. The Ma haplotypes were determined by sequencing two bacterial artificial chromosome clones from G.41 (an apple rootstock of genotype Mama) that cover the two distinct haplotypes at the Ma locus. Gene expression profiling in 18 apple germplasm accessions suggested that Ma1 is the major determinant at the Ma locus controlling fruit acidity as Ma1 is expressed at a much higher level than Ma2 and the Ma1 expression is significantly correlated with fruit titratable acidity (R (2) = 0.4543, P = 0.0021). In the coding sequences of low acidity alleles of Ma1 and Ma2, sequence variations at the amino acid level between Golden Delicious and G.41 were not detected. But the alleles for high acidity vary considerably between the two genotypes. The low acidity allele of Ma1, Ma1-1455A, is mainly characterized by a mutation at base 1455 in the open reading frame. The mutation leads to a premature stop codon that truncates the carboxyl terminus of Ma1-1455A by 84 amino acids compared with Ma1-1455G. A survey of 29 apple germplasm accessions using marker CAPS(1455) that targets the SNP(1455) in Ma1 showed that the CAPS(1455A) allele was associated completely with high pH and highly with low titratable acidity, suggesting that the natural mutation-led truncation is most likely responsible for the abolished function of Ma

Physical mapping of a pollen modifier locus controlling self-incompatibility in apricot and synteny analysis within the Rosaceae.

Science.gov (United States)

Zuriaga, Elena; Molina, Laura; Badenes, María Luisa; Romero, Carlos

2012-06-01

S-locus products (S-RNase and F-box proteins) are essential for the gametophytic self-incompatibility (GSI) specific recognition in Prunus. However, accumulated genetic evidence suggests that other S-locus unlinked factors are also required for GSI. For instance, GSI breakdown was associated with a pollen-part mutation unlinked to the S-locus in the apricot (Prunus armeniaca L.) cv. 'Canino'. Fine-mapping of this mutated modifier gene (M-locus) and the synteny analysis of the M-locus within the Rosaceae are here reported. A segregation distortion loci mapping strategy, based on a selectively genotyped population, was used to map the M-locus. In addition, a bacterial artificial chromosome (BAC) contig was constructed for this region using overlapping oligonucleotides probes, and BAC-end sequences (BES) were blasted against Rosaceae genomes to perform micro-synteny analysis. The M-locus was mapped to the distal part of chr.3 flanked by two SSR markers within an interval of 1.8 cM corresponding to ~364 Kb in the peach (Prunus persica L. Batsch) genome. In the integrated genetic-physical map of this region, BES were mapped against the peach scaffold_3 and BACs were anchored to the apricot map. Micro-syntenic blocks were detected in apple (Malus × domestica Borkh.) LG17/9 and strawberry (Fragaria vesca L.) FG6 chromosomes. The M-locus fine-scale mapping provides a solid basis for self-compatibility marker-assisted selection and for positional cloning of the underlying gene, a necessary goal to elucidate the pollen rejection mechanism in Prunus. In a wider context, the syntenic regions identified in peach, apple and strawberry might be useful to interpret GSI evolution in Rosaceae.

Molecular screening of pituitary adenomas for gene mutations and rearrangements

Energy Technology Data Exchange (ETDEWEB)

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

1993-07-01

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.

Are there gender differences in locus of control specific to alcohol dependence?

Science.gov (United States)

McPherson, Andrew; Martin, Colin R

2017-01-01

To investigate gender differences in locus of control in an alcohol-dependent population. Locus of control helps to explain behaviour in terms of internal (the individual is responsible) or external (outside forces, such as significant other people or chance, are responsible) elements. Past research on gender differences in locus of control in relation to alcohol dependence has shown mixed results. There is a need then to examine gender and locus of control in relation to alcohol dependence to ascertain the veracity of any locus of control differences as a function of gender. The Multidimensional Health Locus of Control form-C was administered to clients from alcohol dependence treatment centres in the West of Scotland. Independent t-tests were carried out to assess gender differences in alcohol dependence severity and internal/external aspects of locus of control. One hundred and eighty-eight (53% females) participants were recruited from a variety of alcohol dependence treatment centres. The majority of participants (72%) came from Alcoholics Anonymous groups. Women revealed a greater internal locus of control compared with men. Women also had a greater 'significant others' locus of control score than men. Men were more reliant on 'chance' and 'doctors' than women. All these trends were not, however, statistically significant. Gender differences in relation to locus of control and alcohol dependence from past studies are ambiguous. This study also found no clear statistically significant differences in locus of control orientation as a function of gender. This article helps nurses to contextualise health behaviours as a result of internal or external forces. It also helps nursing staff to better understand alcohol dependence treatment in relation to self-efficacy and control. Moreover, it highlights an important concept in health education theory. © 2016 John Wiley & Sons Ltd.

Addition of molecular methods to mutation studies with Drosophila melanogaster

International Nuclear Information System (INIS)

Lee, W.R.

1989-01-01

For 80 years, Drosophila melanogaster has been used as a major tool in analyzing Mendelian genetics. By using chromosome inversions that suppress crossing over, geneticists have developed a large number of stocks for mutation analysis. These stocks permit numerous tests for specific locus mutations, lethals at multiple loci on any chromosome, chromosome exchanges, insertions, and deletions. The entire genome can be manipulated for a degree of genetic control not found in other germ-line systems. Recombinant DNA techniques now permit analysis of mutations to the nucleotide level. By combining classical genetic analysis with recombinant DNA techniques, it is possible to analyze mutations that range from chromosome aberrations and multilocus deficiencies to single nucleotide transitions

Site-specific genomic (SSG and random domain-localized (RDL mutagenesis in yeast

Directory of Open Access Journals (Sweden)

Honigberg Saul M

2004-04-01

Full Text Available Abstract Background A valuable weapon in the arsenal available to yeast geneticists is the ability to introduce specific mutations into yeast genome. In particular, methods have been developed to introduce deletions into the yeast genome using PCR fragments. These methods are highly efficient because they do not require cloning in plasmids. Results We have modified the existing method for introducing deletions in the yeast (S. cerevisiae genome using PCR fragments in order to target point mutations to this genome. We describe two PCR-based methods for directing point mutations into the yeast genome such that the final product contains no other disruptions. In the first method, site-specific genomic (SSG mutagenesis, a specific point mutation is targeted into the genome. In the second method, random domain-localized (RDL mutagenesis, a mutation is introduced at random within a specific domain of a gene. Both methods require two sequential transformations, the first transformation integrates the URA3 marker into the targeted locus, and the second transformation replaces URA3 with a PCR fragment containing one or a few mutations. This PCR fragment is synthesized using a primer containing a mutation (SSG mutagenesis or is synthesized by error-prone PCR (RDL mutagenesis. In SSG mutagenesis, mutations that are proximal to the URA3 site are incorporated at higher frequencies than distal mutations, however mutations can be introduced efficiently at distances of at least 500 bp from the URA3 insertion. In RDL mutagenesis, to ensure that incorporation of mutations occurs at approximately equal frequencies throughout the targeted region, this region is deleted at the same time URA3 is integrated. Conclusion SSG and RDL mutagenesis allow point mutations to be easily and efficiently incorporated into the yeast genome without disrupting the native locus.

Neutron-induced mutation experiments. Progress report, March 1, 1976--February 28, 1977

International Nuclear Information System (INIS)

Abrahamson, S.

1976-11-01

Results are from studies of experiments in Drosophila on the relative mutagenic effectiveness of neutrons of different energies employing X-linked recessive lethal and specific locus mutation tests. The energies and doses employed to data are .43 MeV (500, 1000, and 1500 R, in progress), .68 MeV (250, 500, 1000, and 1500 R), 2 and 6 MeV (250 and 500 R), and 15 MeV (250, 500, 1000, 1500 and 3000 R). .68 MeV neutrons appear to have an RBE between 3.3 to 4.5, 15 MeV neutrons an RBE between 1.9 to 2.2, and 2 and 6 MeV neutrons RBE's of intermediate values. The data for both .68 and 15 MeV neutrons do not yet differentiate between a linear and quadratic dose/frequency response curve for the doses studied. The specific locus mutation data also indicate the highest RBE for .68 MeV, followed by 2 and 6 MeV respectively

Complementation analyses for 45 mutations encompassing the pink-eyed dilution (p) locus of the mouse

Energy Technology Data Exchange (ETDEWEB)

Russell, L.B.; Montgomery, C.S.; Cacheiro, N.L.A.; Johnson, D.K. [Oak Ridge National Lab., TN (United States)

1995-12-01

The homozygous and heterozygous phenotypes are described and characterized for 45 new pink-eyed dilution (p) locus mutations, most of them radiation-induced, that affect survival at various stages of mouse development. Cytogenetically detectable aberrations were found in three of the new p mutations (large deletion, inversion, translocation), with band 7C involved in each case. The complementation map developed from the study of 810 types of compound heterozygotes identifies five functional units: jls and jlm (two distinct juvenile-fitness functions, the latter associated with neuromuscular defects), pl-1 and pl-2 (associated with early-postimplantation and preimplantation death, respectively), and nl [neonatal lethality associated with cleft palate (the frequency of rare {open_quotes}escapers{close_quotes} from this defect varied with the genotype)]. Orientation of these units relative to genetic markers is as follows: centromere, Gas-2, pl-1, jls, jlm p, nl (equatable to cp1= Gabrb3); pl-2 probably resides in the c-deletion complex. pl-1 does not mask preimplantation lethals between Gas2 and p; and no genes affecting survival are located between p and cp1. The alleles specifying mottling or darker pigment (generically, p{sup m} and p{sup x}, respectively) probably do not represent deletions of p-coding sequences but could be small rearrangements involving proximal regulatory elements. 43 refs., 5 figs., 7 tabs.

Identification of potential molecular markers of ionizing radiation-induced mutations at the hprt locus in CHO cells

International Nuclear Information System (INIS)

Schwartz, J.L.; Sun, J.; Porter, R.C.

1995-01-01

Using multiplex polymerase chain reaction-based exon deletion analysis, we have analyzed mutations at the hprt locus from independent CHO cell mutants isolated from untreated, 60 Co x-ray-, and 212 Bi-exposed CHO-K1 cello and its radiation-sensitive derivative, xrs-5. In the 71 spontaneous CHO-K1 mutants analyzed, 78% showed no change in exon number or size, 20% showed loss of 1-8 exons (partial deletion), and 3% showed loss of all nine hprt exons (total deletion). Exposure of CHO-K1 cells to 6 Gy of γ rays (10% survival) produced 45% of the 20 mutants analyzed showing partial deletion, and 30% showing total deletion. Exposure to an equitoxic dose of a radiation from 212 Bi, a 220 Rn daughter, resulted in a spectrum similar to the γ-ray spectrum in that more than 75% of the 49 mutants analyzed were deletions. The α-radiation, however, tended to produce larger intragenic deletions that γ radiation. Of the 87 spontaneous xrs-5 mutants analyzed for deletions 44% showed partial deletion, and 14% showed total deletion. Exposure to α radiation (10% survival) resulted in a deletion spectrum similar to that seen in CHO-K1 cells. Of the 49 mutants analyzed, 43% showed no change in exon number or size, 16% showed partial deletion, and 41% showed total deletion. While the defect in xrs-5 has a profound effect on spontaneous mutation spectra, it does not appear to affect α-induced mutation spectra

Inferring Demographic History Using Two-Locus Statistics.

Science.gov (United States)

Ragsdale, Aaron P; Gutenkunst, Ryan N

2017-06-01

Population demographic history may be learned from contemporary genetic variation data. Methods based on aggregating the statistics of many single loci into an allele frequency spectrum (AFS) have proven powerful, but such methods ignore potentially informative patterns of linkage disequilibrium (LD) between neighboring loci. To leverage such patterns, we developed a composite-likelihood framework for inferring demographic history from aggregated statistics of pairs of loci. Using this framework, we show that two-locus statistics are more sensitive to demographic history than single-locus statistics such as the AFS. In particular, two-locus statistics escape the notorious confounding of depth and duration of a bottleneck, and they provide a means to estimate effective population size based on the recombination rather than mutation rate. We applied our approach to a Zambian population of Drosophila melanogaster Notably, using both single- and two-locus statistics, we inferred a substantially lower ancestral effective population size than previous works and did not infer a bottleneck history. Together, our results demonstrate the broad potential for two-locus statistics to enable powerful population genetic inference. Copyright © 2017 by the Genetics Society of America.

Further evidence for elevated human minisatellite mutation rate in Belarus eight years after the Chernobyl accident

International Nuclear Information System (INIS)

Dubrova, Yuri E.; Buard, Jerome; Jeffreys, Alec J.; Nesterov, Valeri N.; Krouchinsky, Nicolay G.; Ostapenko, Vladislav A.; Vergnaud, Gilles; Giraudeau, Fabienne

1997-01-01

Analysis of germline mutation rate at human minisatellites among children born in areas of the Mogilev district of Belarus heavily polluted after the Chernobyl accident has been extended, both by recruiting more families from the affected region and by using five additional minisatellite probes, including multi-locus probe 33.6 and four hypervariable single-locus probes. These additional data confirmed a twofold higher mutation rate in exposed families compared with non-irradiated families from the United Kingdom. An elevated rate was seen at all three independent sets of minisatellites (detected separately by multi-locus probes 33.15, 33.6 and six single-locus probes), indicating a generalised increase in minisatellite germline mutation rate in the Belarus families. Within the Belarus cohort, mutation rate was significantly greater in families with higher parental radiation dose estimated for chronic external and internal exposure to caesium-137, consistent with radiation induction of germline mutation. The spectra of mutation seen in the unexposed and exposed families were indistinguishable, suggesting that increased mutation observed over multiple loci arises indirectly by some mechanism that enhances spontaneous minisatellite mutation

Analysis of the ABCA4 genomic locus in Stargardt disease

DEFF Research Database (Denmark)

Zernant, Jana; Xie, Yajing Angela; Ayuso, Carmen

2014-01-01

excluded since they were not conserved in non-human primates, were frequent in African populations and, therefore, represented ancestral, and not disease-associated, variants. The sequence variability in the ABCA4 locus is extensive and the non-coding sequences do not harbor frequent mutations in STGD...... patients of European-American descent. Defining disease-associated alleles in the ABCA4 locus requires exceptionally well characterized large cohorts and extensive analyses by a combination of various approaches....

Quantification and analysis of reverse mutations at the hgprt locus in Chinese hamster ovary cells

Energy Technology Data Exchange (ETDEWEB)

Fuscoe, J.C.; O' Neill, J.P.; Machanoff, R.; Hsie, A.W.

1982-01-01

An assay is described for the quantification of reverse mutations at the hypoxanthine-guanine phosphoribosyltransferase (hgprt) locus in Chinese hamster ovary cells utilizing the selective agent L-azaserine (AS). Conditions are defined in terms of optimal AS concentration, cell density, and phenotypic expression time. After treatment, replicate cultures of 10/sup 6/ cells are allowed a 48-h phenotypic expression time in 100-mm plates. AS (10..mu..M) is then added directly to the growing culture and AS-resistant (AS/sup r/) cells form visible colonies. This assay is used to quantify ICR-191-, ICR-170-, and N-ethyl-N-nitrosourea-induced reversion of independently isolated HGPRT/sup -/ clones. The AS/sup r/ phenotype is characterized both physiologically and biochemically. All AS/sup r/ clones isolated are stably resistant to AS and aminopterin but sensitive to 6-thioguanine. They also have re-expressed HGPRT enzyme. In addition, several revertants are shown to contain altered HGPRT.

A locus for isolated cataract on human Xp.

Science.gov (United States)

Francis, P J; Berry, V; Hardcastle, A J; Maher, E R; Moore, A T; Bhattacharya, S S

2002-02-01

To genetically map the gene causing isolated X linked cataract in a large European pedigree. Using the patient registers at Birmingham Women's Hospital, UK, we identified and examined 23 members of a four generation family with nuclear cataract. Four of six affected males also had complex congenital heart disease. Pedigree data were collated and leucocyte DNA extracted from venous blood. Linkage analysis by PCR based microsatellite marker genotyping was used to identify the disease locus and mutations within candidate genes screened by direct sequencing. The disease locus was genetically refined to chromosome Xp22, within a 3 cM linkage interval flanked by markers DXS9902 and DXS999 (Zmax=3.64 at theta=0 for marker DXS8036). This is the first report of a locus for isolated inherited cataract on the X chromosome. The disease interval lies within the Nance-Horan locus suggesting allelic heterogeneity. The apparent association with congenital cardiac anomalies suggests a possible new oculocardiac syndrome.

Efficient CRISPR-Cas9-mediated generation of knockin human pluripotent stem cells lacking undesired mutations at the targeted locus.

Science.gov (United States)

Merkle, Florian T; Neuhausser, Werner M; Santos, David; Valen, Eivind; Gagnon, James A; Maas, Kristi; Sandoe, Jackson; Schier, Alexander F; Eggan, Kevin

2015-05-12

The CRISPR-Cas9 system has the potential to revolutionize genome editing in human pluripotent stem cells (hPSCs), but its advantages and pitfalls are still poorly understood. We systematically tested the ability of CRISPR-Cas9 to mediate reporter gene knockin at 16 distinct genomic sites in hPSCs. We observed efficient gene targeting but found that targeted clones carried an unexpectedly high frequency of insertion and deletion (indel) mutations at both alleles of the targeted gene. These indels were induced by Cas9 nuclease, as well as Cas9-D10A single or dual nickases, and often disrupted gene function. To overcome this problem, we designed strategies to physically destroy or separate CRISPR target sites at the targeted allele and developed a bioinformatic pipeline to identify and eliminate clones harboring deleterious indels at the other allele. This two-pronged approach enables the reliable generation of knockin hPSC reporter cell lines free of unwanted mutations at the targeted locus. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Detection of EGFR mutations with mutation-specific antibodies in stage IV non-small-cell lung cancer

Directory of Open Access Journals (Sweden)

Viteri Santiago

2010-12-01

Full Text Available Abstract Background Immunohistochemistry (IHC with mutation-specific antibodies may be an ancillary method of detecting EGFR mutations in lung cancer patients. Methods EGFR mutation status was analyzed by DNA assays, and compared with IHC results in five non-small-cell lung cancer (NSCLC cell lines and tumor samples from 78 stage IV NSCLC patients. Results IHC correctly identified del 19 in the H1650 and PC9 cell lines, L858R in H1975, and wild-type EGFR in H460 and A549, as well as wild-type EGFR in tumor samples from 22 patients. IHC with the mAb against EGFR with del 19 was highly positive for the protein in all 17 patients with a 15-bp (ELREA deletion in exon 19, whereas in patients with other deletions, IHC was weakly positive in 3 cases and negative in 9 cases. IHC with the mAb against the L858R mutation showed high positivity for the protein in 25/27 (93% patients with exon 21 EGFR mutations (all with L858R but did not identify the L861Q mutation in the remaining two patients. Conclusions IHC with mutation-specific mAbs against EGFR is a promising method for detecting EGFR mutations in NSCLC patients. However these mAbs should be validated with additional studies to clarify their possible role in routine clinical practice for screening EGFR mutations in NSCLC patients.

Bistability and hysteresis of the 'Secteur' differentiation are controlled by a two-gene locus in Nectria haematococca

Directory of Open Access Journals (Sweden)

Daboussi Marie-Josée

2004-08-01

Full Text Available Abstract Background Bistability and hysteresis are increasingly recognized as major properties of regulatory networks governing numerous biological phenomena, such as differentiation and cell cycle progression. The full scope of the underlying molecular mechanisms leading to bistability and hysteresis remains elusive. Nectria haemaotcocca, a saprophytic or pathogenic fungus with sexual reproduction, exhibits a bistable morphological modification characterized by a reduced growth rate and an intense pigmentation. Bistability is triggered by the presence or absence of σ, a cytoplasmic determinant. This determinant spreads in an infectious manner in the hyphae of the growing margin, insuring hysteresis of the differentiation. Results Seven mutants specifically affected in the generation of σ were selected through two different screening strategies. The s1 and s2 mutations completely abolish the generation of σ and of its morphological expression, the Secteur. The remaining five mutations promote its constitutive generation, which determines an intense pigmentation but not growth alteration. The seven mutations map at the same locus, Ses (for 'Secteur-specific'. The s2 mutant was obtained by an insertional mutagenesis strategy, which permitted the cloning of the Ses locus. Sequence and transcription analysis reveals that Ses is composed of two closely linked genes, SesA, mutated in the s1 and s2 mutant strains, and SesB, mutated in the s* mutant strains. SesB shares sequence similarity with animal and fungal putative proteins, with potential esterase/lipase/thioesterase activity, whereas SesA is similar to proteins of unknown function present only in the filamentous fungi Fusarium graminearum and Podospora anserina. Conclusions The cloning of Ses provides evidence that a system encoded by two linked genes directs a bistable and hysteretic switch in a eukaryote. Atypical regulatory relations between the two proteins may account for the hysteresis

Bistability and hysteresis of the 'Secteur' differentiation are controlled by a two-gene locus in Nectria haematococca

Science.gov (United States)

Graziani, Stéphane; Silar, Philippe; Daboussi, Marie-Josée

2004-01-01

Background Bistability and hysteresis are increasingly recognized as major properties of regulatory networks governing numerous biological phenomena, such as differentiation and cell cycle progression. The full scope of the underlying molecular mechanisms leading to bistability and hysteresis remains elusive. Nectria haemaotcocca, a saprophytic or pathogenic fungus with sexual reproduction, exhibits a bistable morphological modification characterized by a reduced growth rate and an intense pigmentation. Bistability is triggered by the presence or absence of σ, a cytoplasmic determinant. This determinant spreads in an infectious manner in the hyphae of the growing margin, insuring hysteresis of the differentiation. Results Seven mutants specifically affected in the generation of σ were selected through two different screening strategies. The s1 and s2 mutations completely abolish the generation of σ and of its morphological expression, the Secteur. The remaining five mutations promote its constitutive generation, which determines an intense pigmentation but not growth alteration. The seven mutations map at the same locus, Ses (for 'Secteur-specific'). The s2 mutant was obtained by an insertional mutagenesis strategy, which permitted the cloning of the Ses locus. Sequence and transcription analysis reveals that Ses is composed of two closely linked genes, SesA, mutated in the s1 and s2 mutant strains, and SesB, mutated in the s* mutant strains. SesB shares sequence similarity with animal and fungal putative proteins, with potential esterase/lipase/thioesterase activity, whereas SesA is similar to proteins of unknown function present only in the filamentous fungi Fusarium graminearum and Podospora anserina. Conclusions The cloning of Ses provides evidence that a system encoded by two linked genes directs a bistable and hysteretic switch in a eukaryote. Atypical regulatory relations between the two proteins may account for the hysteresis of Secteur differentiation

A/α-specific effect of the mms3 mutation on ultraviolet mutagenesis in Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Martin, P.; Prakash, L.; Prakash, S.

1981-01-01

A new gene involved in error-prone repair of ultraviolet (uv) damage has been identified in Saccharomyces cerevisiae by the mms3-1 mutation. Uv-induced reversion is reduced in diploids that are homozygous for mms3-1, only if they are also heterozygous (MATa/MATα) at the mating type locus. The mms3-1 mutation has no effect on uv-induced reversion either in haploids or MATa/MATα or MATα/MATα diploids. The mutation confers sensitivity to uv and methyl methane sulfonate in both haploids and diploids. Even though mutation induction by uv is restored to wild-type levels in MATa/MATa mms3-1/mms3-1 or MATα/MATα mms3-1/mms3-1 diploids, such strains still retain sensitivity to the lethal effects of uv. Survival after uv irradiation in mms3-1 rad double mutant combinations indicates that mms3-1 is epistatic to rad6-1 whereas non-epistatic interactions are observed with rad3 and rad52 mutants. When present in the homozygous state in MATa/MATα his1-1/his1-315 heteroallelic diploids, mms3-1 was found to lower uv-induced mitotic recombination

Work locus of control and its relationship to stress perception, related affections, attitudes and behaviours from a domain-specific perspective.

Science.gov (United States)

Tong, Jiajin; Wang, Lei

2012-08-01

This research aims to examine the value of applying the Work Locus of Control Scale in predicting work-related outcomes. Study 1 surveyed 323 employees from different companies in China and found that the domain-specific scale was more predictive than the general scale in predicting perceived stressors, rather than in predicting organizational affective commitment and altruistic behaviour. Study 2 applied a multi-wave and multi-source design and used commensurate Likert scales to measure work and general locus of control. Participants were 344 employees from one corporation. Work locus of control was found to be more useful in predicting supervisor-rated job performance, conscientious and altruistic behaviours. These findings help understand the theory-based and measurement-based reasons for the advantages of using domain-specific measures. They claim the importance for employing the domain-specific measure to predict work-related perceptions and behaviours. Implications for the theory and practice are discussed. Copyright © 2011 John Wiley & Sons, Ltd.

19p13.1 is a triple-negative-specific breast cancer susceptibility locus

DEFF Research Database (Denmark)

Stevens, Kristen N; Fredericksen, Zachary; Vachon, Celine M

2012-01-01

(PR), and human epidermal growth factor receptor-2 (HER2) status, using 48,869 breast cancer cases and 49,787 controls from the Breast Cancer Association Consortium (BCAC). Variants from 19p13.1 were not associated with breast cancer overall or with ER-positive breast cancer but were significantly......The 19p13.1 breast cancer susceptibility locus is a modifier of breast cancer risk in BRCA1 mutation carriers and is also associated with the risk of ovarian cancer. Here, we investigated 19p13.1 variation and risk of breast cancer subtypes, defined by estrogen receptor (ER), progesterone receptor...... associated with ER-negative breast cancer risk [rs8170 OR, 1.10; 95% confidence interval (CI), 1.05-1.15; P = 3.49 × 10(-5)] and triple-negative (ER-, PR-, and HER2-negative) breast cancer (rs8170: OR, 1.22; 95% CI, 1.13-1.31; P = 2.22 × 10(-7)). However, rs8170 was no longer associated with ER...

Mutation rates at 42 Y chromosomal short tandem repeats in Chinese Han population in Eastern China.

Science.gov (United States)

Wu, Weiwei; Ren, Wenyan; Hao, Honglei; Nan, Hailun; He, Xin; Liu, Qiuling; Lu, Dejian

2018-01-31

Mutation analysis of 42 Y chromosomal short tandem repeats (Y-STRs) loci was performed using a sample of 1160 father-son pairs from the Chinese Han population in Eastern China. The results showed that the average mutation rate across the 42 Y-STR loci was 0.0041 (95% CI 0.0036-0.0047) per locus per generation. The locus-specific mutation rates varied from 0.000 to 0.0190. No mutation was found at DYS388, DYS437, DYS448, DYS531, and GATA_H4. DYS627, DYS570, DYS576, and DYS449 could be classified as rapidly mutating Y-STRs, with mutation rates higher than 1.0 × 10 -2 . DYS458, DYS630, and DYS518 were moderately mutating Y-STRs, with mutation rates ranging from 8 × 10 -3 to 1 × 10 -2 . Although the characteristics of the Y-STR mutations were consistent with those in previous studies, mutation rate differences between our data and previous published data were found at some rapidly mutating Y-STRs. The single-copy loci located on the short arm of the Y chromosome (Yp) showed relatively higher mutation rates more frequently than the multi-copy loci. These results will not only extend the data for Y-STR mutations but also be important for kinship analysis, paternal lineage identification, and family relationship reconstruction in forensic Y-STR analysis.

eMelanoBase: an online locus-specific variant database for familial melanoma.

Science.gov (United States)

Fung, David C Y; Holland, Elizabeth A; Becker, Therese M; Hayward, Nicholas K; Bressac-de Paillerets, Brigitte; Mann, Graham J

2003-01-01

A proportion of melanoma-prone individuals in both familial and non-familial contexts has been shown to carry inactivating mutations in either CDKN2A or, rarely, CDK4. CDKN2A is a complex locus that encodes two unrelated proteins from alternately spliced transcripts that are read in different frames. The alpha transcript (exons 1alpha, 2, and 3) produces the p16INK4A cyclin-dependent kinase inhibitor, while the beta transcript (exons 1beta and 2) is translated as p14ARF, a stabilizing factor of p53 levels through binding to MDM2. Mutations in exon 2 can impair both polypeptides and insertions and deletions in exons 1alpha, 1beta, and 2, which can theoretically generate p16INK4A-p14ARF fusion proteins. No online database currently takes into account all the consequences of these genotypes, a situation compounded by some problematic previous annotations of CDKN2A-related sequences and descriptions of their mutations. As an initiative of the international Melanoma Genetics Consortium, we have therefore established a database of germline variants observed in all loci implicated in familial melanoma susceptibility. Such a comprehensive, publicly accessible database is an essential foundation for research on melanoma susceptibility and its clinical application. Our database serves two types of data as defined by HUGO. The core dataset includes the nucleotide variants on the genomic and transcript levels, amino acid variants, and citation. The ancillary dataset includes keyword description of events at the transcription and translation levels and epidemiological data. The application that handles users' queries was designed in the model-view-controller architecture and was implemented in Java. The object-relational database schema was deduced using functional dependency analysis. We hereby present our first functional prototype of eMelanoBase. The service is accessible via the URL www.wmi.usyd.edu.au:8080/melanoma.html. Copyright 2002 Wiley-Liss, Inc.

Locus specificity in the mutability of mouse lymphoma strain LY-S

International Nuclear Information System (INIS)

Evans, H.H.; Mencl, J.; Horng, M.F.

1985-01-01

Mouse lymphoma L5178Y strains, LY-R and LY-S, are closely related but differ in their sensitivity to the lethal effects of radiation and various chemicals. Strain LY-S was originally isolated in 1961 following a spontaneous change in the sensitivity of cultured LY-R cells to ionizing radiation. The authors previously reported that, although strain LY-S is more sensitive to the lethal effects of ionizing radiation and alkylating agents than strain LY-R, it is markedly less mutable than strain LY-R at the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus. The isolated sublines of strains LY-R and LY-S which are heterozygous at the thymidine kinase (TK) locus. The LY-S TK+/- heterozygote, like its TK+/+ parent, is more sensitive to the lethal effects of ionizing radiation and alkylating agents and less mutable at the HGPRT locus by these agents than the LY-R TK+/- heterozygote. However, the LY-S heterozygote is 100 times more mutable by these agents at the TK locus than at the HGRT locus. In contrast to LY-R, the majority of the spontaneous and induced LY-S TK-/- mutants form small colonies in the presence of trifluorothymidine, indicating that in the LY-S heterozygote, the inactivation of the TK gene is accompanied by damage to, or rearrangement of neighboring genes

DRUMS: a human disease related unique gene mutation search engine.

Science.gov (United States)

Li, Zuofeng; Liu, Xingnan; Wen, Jingran; Xu, Ye; Zhao, Xin; Li, Xuan; Liu, Lei; Zhang, Xiaoyan

2011-10-01

With the completion of the human genome project and the development of new methods for gene variant detection, the integration of mutation data and its phenotypic consequences has become more important than ever. Among all available resources, locus-specific databases (LSDBs) curate one or more specific genes' mutation data along with high-quality phenotypes. Although some genotype-phenotype data from LSDB have been integrated into central databases little effort has been made to integrate all these data by a search engine approach. In this work, we have developed disease related unique gene mutation search engine (DRUMS), a search engine for human disease related unique gene mutation as a convenient tool for biologists or physicians to retrieve gene variant and related phenotype information. Gene variant and phenotype information were stored in a gene-centred relational database. Moreover, the relationships between mutations and diseases were indexed by the uniform resource identifier from LSDB, or another central database. By querying DRUMS, users can access the most popular mutation databases under one interface. DRUMS could be treated as a domain specific search engine. By using web crawling, indexing, and searching technologies, it provides a competitively efficient interface for searching and retrieving mutation data and their relationships to diseases. The present system is freely accessible at http://www.scbit.org/glif/new/drums/index.html. © 2011 Wiley-Liss, Inc.

Murine and human b locus pigmentation genes encode a glycoprotein (gp75) with catalase activity

International Nuclear Information System (INIS)

Halaban, R.; Moellmann, G.

1990-01-01

Melanogenesis is regulated in large part by tyrosinase, and defective tyrosinase leads to albinism. The mechanisms for other pigmentation determinants (e.g., those operative in tyrosinase-positive albinism and in murine coat-color mutants) are not yet known. One murine pigmentation gene, the brown (b) locus, when mutated leads to a brown (b/b) or hypopigmentated (B lt /B lt ) coat versus the wild-type black (B/B). The authors show that the b locus codes for a glycoprotein with the activity of a catalase (catalase B). Only the c locus protein is a tyrosinase. Because peroxides may be by-products of melanogenic activity and hydrogen peroxide in particular is known to destroy melanin precursors and melanin, they conclude that pigmentation is controlled not only by tyrosinase but also by a hydroperoxidase. The studies indicate that catalase B is identical with gp75, a known human melanosomal glycoprotein; that the b mutation is in a heme-associated domain; and that the B lt mutation renders the protein susceptible to rapid proteolytic degradation

A large duplication involving the IHH locus mimics acrocallosal syndrome.

Science.gov (United States)

Yuksel-Apak, Memnune; Bögershausen, Nina; Pawlik, Barbara; Li, Yun; Apak, Selcuk; Uyguner, Oya; Milz, Esther; Nürnberg, Gudrun; Karaman, Birsen; Gülgören, Ayan; Grzeschik, Karl-Heinz; Nürnberg, Peter; Kayserili, Hülya; Wollnik, Bernd

2012-06-01

Indian hedgehog (Ihh) signaling is a major determinant of various processes during embryonic development and has a pivotal role in embryonic skeletal development. A specific spatial and temporal expression of Ihh within the developing limb buds is essential for accurate digit outgrowth and correct digit number. Although missense mutations in IHH cause brachydactyly type A1, small tandem duplications involving the IHH locus have recently been described in patients with mild syndactyly and craniosynostosis. In contrast, a ∼600-kb deletion 5' of IHH in the doublefoot mouse mutant (Dbf) leads to severe polydactyly without craniosynostosis, but with craniofacial dysmorphism. We now present a patient resembling acrocallosal syndrome (ACS) with extensive polysyndactyly of the hands and feet, craniofacial abnormalities including macrocephaly, agenesis of the corpus callosum, dysplastic and low-set ears, severe hypertelorism and profound psychomotor delay. Single-nucleotide polymorphism (SNP) array copy number analysis identified a ∼900-kb duplication of the IHH locus, which was confirmed by an independent quantitative method. A fetus from a second pregnancy of the mother by a different spouse showed similar craniofacial and limb malformations and the same duplication of the IHH-locus. We defined the exact breakpoints and showed that the duplications are identical tandem duplications in both sibs. No copy number changes were observed in the healthy mother. To our knowledge, this is the first report of a human phenotype similar to the Dbf mutant and strikingly overlapping with ACS that is caused by a copy number variation involving the IHH locus on chromosome 2q35.

Characterization of additional rabbit IgM allotypes and the effect of suppression of a VH locus allotypes on the expression of n Cμ locus allotype

International Nuclear Information System (INIS)

Gilman-Sachs, A.; Roux, K.H.; Horing, W.J.; Dray, S.

1982-01-01

Anti-allotype antisera were produced that identified eight rabbit IgM allotypic specificities, n80, n81, n82, n83, n84, n85, n86, and n87. The n locus Cμ genes controlling these IgM allotypic specificities are closely linked to the a (VH subgroup) locus. The genes controlling these allotypic specificities were found to be in the heavy chain chromosomal region and were assigned to 11 haplotypes present in our rabbit colony. The n locus and a locus genes appeared in the haplotypes in six combinations: a 1 n 81 , a 2 n/sup 81,n87/, a 1 n/sup 80,83/, a 2 n/sup 80,82,87/, a 3 n/sup 81,84,85/ and a 3 n/sup 80,84,86,87/. By radioprecipitation analysis, 70 to 80% of serum IgM reacts with the antiserum directed to each n locus allotypic specificity found encoded in one haplotype; thus, each allotypic specificity of the haplotype is present on the same IgM molecule. When sera from a locus allotype-suppressed homozygous rabbits were tested for expression of each n locus allotypic specificity, n80, n81, and n87 were still expressed, whereas n82, n83, n84, n85, and n86 were not. These data provide direct evidence that some IgM specificities are expressed independently of the a locus (i.e., ''true''), and other s are dependent on the expression of an a locus specificity (i.e., conformational). The expression of the ''true'' allotypic specificities probably reflects genetic control of the germline Cμ gene, and the expression of ''conformationally dependent'' allotypic specificities probably reflects the interaction of VH and Cμ gene segments. This distinction is important and must be recognized when evaluating the genetics and structure of the IgM molecule

Effect of Ku80 deficiency on mutation frequencies and spectra at a LacZ reporter locus in mouse tissues and cells.

Directory of Open Access Journals (Sweden)

Rita A Busuttil

Full Text Available Non-homologous end joining (NHEJ is thought to be an important mechanism for preventing the adverse effects of DNA double strand breaks (DSBs and its absence has been associated with premature aging. To investigate the effect of inactivated NHEJ on spontaneous mutation frequencies and spectra in vivo and in cultured cells, we crossed a Ku80-deficient mouse with mice harboring a lacZ-plasmid-based mutation reporter. We analyzed various organs and tissues, as well as cultured embryonic fibroblasts, for mutations at the lacZ locus. When comparing mutant with wild-type mice, we observed a significantly higher number of genome rearrangements in liver and spleen and a significantly lower number of point mutations in liver and brain. The reduced point mutation frequency was not due to a decrease in small deletion mutations thought to be a hallmark of NHEJ, but could be a consequence of increased cellular responses to unrepaired DSBs. Indeed, we found a substantial increase in persistent 53BP1 and gammaH2AX DNA damage foci in Ku80-/- as compared to wild-type liver. Treatment of cultured Ku80-deficient or wild-type embryonic fibroblasts, either proliferating or quiescent, with hydrogen peroxide or bleomycin showed no differences in the number or type of induced genome rearrangements. However, after such treatment, Ku80-deficient cells did show an increased number of persistent DNA damage foci. These results indicate that Ku80-dependent repair of DNA damage is predominantly error-free with the effect of alternative more error-prone pathways creating genome rearrangements only detectable after extended periods of time, i.e., in young adult animals. The observed premature aging likely results from a combination of increased cellular senescence and an increased load of stable, genome rearrangements.

Mutation update on the CHD7 gene involved in CHARGE syndrome

DEFF Research Database (Denmark)

Janssen, Nicole; Bergman, Jorieke E H; Swertz, Morris A

2012-01-01

, for example, the central nervous system, eye, ear, nose, and mediastinal organs, are variably involved. In this article, we review all the currently described CHD7 variants, including 183 new pathogenic mutations found by our laboratories. In total, we compiled 528 different pathogenic CHD7 alterations from......, predominantly arginine to stop codon mutations. We built a locus-specific database listing all the variants that is easily accessible at www.CHD7.org. In addition, we summarize the latest data on CHD7 expression studies, animal models, and functional studies, and we discuss the latest clinical insights...

Accurate CpG and non-CpG cytosine methylation analysis by high-throughput locus-specific pyrosequencing in plants.

Science.gov (United States)

How-Kit, Alexandre; Daunay, Antoine; Mazaleyrat, Nicolas; Busato, Florence; Daviaud, Christian; Teyssier, Emeline; Deleuze, Jean-François; Gallusci, Philippe; Tost, Jörg

2015-07-01

Pyrosequencing permits accurate quantification of DNA methylation of specific regions where the proportions of the C/T polymorphism induced by sodium bisulfite treatment of DNA reflects the DNA methylation level. The commercially available high-throughput locus-specific pyrosequencing instruments allow for the simultaneous analysis of 96 samples, but restrict the DNA methylation analysis to CpG dinucleotide sites, which can be limiting in many biological systems. In contrast to mammals where DNA methylation occurs nearly exclusively on CpG dinucleotides, plants genomes harbor DNA methylation also in other sequence contexts including CHG and CHH motives, which cannot be evaluated by these pyrosequencing instruments due to software limitations. Here, we present a complete pipeline for accurate CpG and non-CpG cytosine methylation analysis at single base-resolution using high-throughput locus-specific pyrosequencing. The devised approach includes the design and validation of PCR amplification on bisulfite-treated DNA and pyrosequencing assays as well as the quantification of the methylation level at every cytosine from the raw peak intensities of the Pyrograms by two newly developed Visual Basic Applications. Our method presents accurate and reproducible results as exemplified by the cytosine methylation analysis of the promoter regions of two Tomato genes (NOR and CNR) encoding transcription regulators of fruit ripening during different stages of fruit development. Our results confirmed a significant and temporally coordinated loss of DNA methylation on specific cytosines during the early stages of fruit development in both promoters as previously shown by WGBS. The manuscript describes thus the first high-throughput locus-specific DNA methylation analysis in plants using pyrosequencing.

Establishment of novel monoclonal antibodies KMab-1 and MMab-1 specific for IDH2 mutations

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Mika Kato [Regional Innovation Strategy Support Program, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 (Japan); Molecular Tumor Marker Research Team, Global COE Program, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Morita, Shunpei; Tsujimoto, Yuta; Yanagiya, Ryo; Nasu, Kana; Sasaki, Hiroko [Molecular Tumor Marker Research Team, Global COE Program, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Hozumi, Yasukazu; Goto, Kaoru [Department of Anatomy and Cell Biology, Yamagata University School of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Natsume, Atsushi [Department of Neurosurgery, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan); Watanabe, Mika [Department of Pathology and Histotechnology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 (Japan); Kumabe, Toshihiro [Department of Neurosurgery, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574 (Japan); Takano, Shingo [Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575 (Japan); Kato, Yukinari, E-mail: yukinari-k@bea.hi-ho.ne.jp [Regional Innovation Strategy Support Program, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575 (Japan); Molecular Tumor Marker Research Team, Global COE Program, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan)

2013-03-01

Highlights: ► IDH1/2 mutations are early and frequent genetic alterations in gliomas. ► We established anti-mutated IDH2-specific mAbs KMab-1 and MMab-1. ► KMab-1 or MMab-1 specifically reacted with mutated IDH2 in ELISA. ► MMab-1 specifically stained IDH2-R172M-expressing CHO cells in ICC. ► MMab-1 specifically stained IDH2-R172M-expressing gliomas in IHC. - Abstract: Isocitrate dehydrogenase 1/2 (IDH1/2) mutations have been detected in gliomas, cartilaginous tumors, and leukemias. IDH1/2 mutations are early and frequent genetic alterations, are specific to a single codon in the conserved and functionally important Arginine 132 (R132) in IDH1 and Arginine 172 (R172) in IDH2. We previously established several monoclonal antibodies (mAbs), which are specific for IDH1 mutations: clones IMab-1 or HMab-1 against IDH1-R132H or clone SMab-1 against IDH1-R132S. However, specific mAbs against IDH2 mutations have not been reported. To establish IDH2-mutation-specific mAbs, we immunized mice or rats with each mutation-containing IDH2 peptides including IDH2-R172K and IDH2-R172M. After cell fusion, IDH2 mutation-specific mAbs were screened in Enzyme-Linked Immunosorbent Assay (ELISA). Established mAbs KMab-1 and MMab-1 reacted with the IDH2-R172K and IDH2-R172M peptides, respectively, but not with IDH2-wild type (WT) in ELISA. Western-blot analysis also showed that KMab-1 and MMab-1 reacted with the IDH2-R172K and IDH2-R172M recombinant proteins, respectively, not with IDH2-WT or other IDH2 mutants, indicating that KMab-1 and MMab-1 are IDH2-mutation-specific. Furthermore, MMab-1 specifically stained the IDH2-R172M-expressing cells in immunocytochemistry, but did not stain IDH2-WT and other IDH2-mutation-containing cells. In immunohistochemical analysis, MMab-1 specifically stained IDH2-R172M-expressing glioma. This is the first report to establish anti-IDH2-mutation-specific mAbs, which could be useful in diagnosis of mutation-bearing tumors.

Establishment of novel monoclonal antibodies KMab-1 and MMab-1 specific for IDH2 mutations

International Nuclear Information System (INIS)

Kaneko, Mika Kato; Morita, Shunpei; Tsujimoto, Yuta; Yanagiya, Ryo; Nasu, Kana; Sasaki, Hiroko; Hozumi, Yasukazu; Goto, Kaoru; Natsume, Atsushi; Watanabe, Mika; Kumabe, Toshihiro; Takano, Shingo; Kato, Yukinari

2013-01-01

Highlights: ► IDH1/2 mutations are early and frequent genetic alterations in gliomas. ► We established anti-mutated IDH2-specific mAbs KMab-1 and MMab-1. ► KMab-1 or MMab-1 specifically reacted with mutated IDH2 in ELISA. ► MMab-1 specifically stained IDH2-R172M-expressing CHO cells in ICC. ► MMab-1 specifically stained IDH2-R172M-expressing gliomas in IHC. - Abstract: Isocitrate dehydrogenase 1/2 (IDH1/2) mutations have been detected in gliomas, cartilaginous tumors, and leukemias. IDH1/2 mutations are early and frequent genetic alterations, are specific to a single codon in the conserved and functionally important Arginine 132 (R132) in IDH1 and Arginine 172 (R172) in IDH2. We previously established several monoclonal antibodies (mAbs), which are specific for IDH1 mutations: clones IMab-1 or HMab-1 against IDH1-R132H or clone SMab-1 against IDH1-R132S. However, specific mAbs against IDH2 mutations have not been reported. To establish IDH2-mutation-specific mAbs, we immunized mice or rats with each mutation-containing IDH2 peptides including IDH2-R172K and IDH2-R172M. After cell fusion, IDH2 mutation-specific mAbs were screened in Enzyme-Linked Immunosorbent Assay (ELISA). Established mAbs KMab-1 and MMab-1 reacted with the IDH2-R172K and IDH2-R172M peptides, respectively, but not with IDH2-wild type (WT) in ELISA. Western-blot analysis also showed that KMab-1 and MMab-1 reacted with the IDH2-R172K and IDH2-R172M recombinant proteins, respectively, not with IDH2-WT or other IDH2 mutants, indicating that KMab-1 and MMab-1 are IDH2-mutation-specific. Furthermore, MMab-1 specifically stained the IDH2-R172M-expressing cells in immunocytochemistry, but did not stain IDH2-WT and other IDH2-mutation-containing cells. In immunohistochemical analysis, MMab-1 specifically stained IDH2-R172M-expressing glioma. This is the first report to establish anti-IDH2-mutation-specific mAbs, which could be useful in diagnosis of mutation-bearing tumors

Linking genotypes database with locus-specific database and genotype-phenotype correlation in phenylketonuria.

Science.gov (United States)

Wettstein, Sarah; Underhaug, Jarl; Perez, Belen; Marsden, Brian D; Yue, Wyatt W; Martinez, Aurora; Blau, Nenad

2015-03-01

The wide range of metabolic phenotypes in phenylketonuria is due to a large number of variants causing variable impairment in phenylalanine hydroxylase function. A total of 834 phenylalanine hydroxylase gene variants from the locus-specific database PAHvdb and genotypes of 4181 phenylketonuria patients from the BIOPKU database were characterized using FoldX, SIFT Blink, Polyphen-2 and SNPs3D algorithms. Obtained data was correlated with residual enzyme activity, patients' phenotype and tetrahydrobiopterin responsiveness. A descriptive analysis of both databases was compiled and an interactive viewer in PAHvdb database was implemented for structure visualization of missense variants. We found a quantitative relationship between phenylalanine hydroxylase protein stability and enzyme activity (r(s) = 0.479), between protein stability and allelic phenotype (r(s) = -0.458), as well as between enzyme activity and allelic phenotype (r(s) = 0.799). Enzyme stability algorithms (FoldX and SNPs3D), allelic phenotype and enzyme activity were most powerful to predict patients' phenotype and tetrahydrobiopterin response. Phenotype prediction was most accurate in deleterious genotypes (≈ 100%), followed by homozygous (92.9%), hemizygous (94.8%), and compound heterozygous genotypes (77.9%), while tetrahydrobiopterin response was correctly predicted in 71.0% of all cases. To our knowledge this is the largest study using algorithms for the prediction of patients' phenotype and tetrahydrobiopterin responsiveness in phenylketonuria patients, using data from the locus-specific and genotypes database.

Development of a human somatic mutation detection method--GPA assay

International Nuclear Information System (INIS)

Mao Jianping; Dong Yan; Liu Bin; Lin Ruxian; Sun Zhixian

2000-01-01

Objective: To study the damage to human body caused by environmental radiation, and supervise the somatic mutations. Methods: Three monoclonal antibodies specific to M-type(3G4), N-type(6A8), and MN-type (3C5) of glycophorin A, respectively, were prepared. Fluorescence or biotin conjugated antibodies were bound specifically to formalin and/or dimethyl suber-imidate fixed erythrocytes. M, MN and N type cells were divided by cytometry to demonstrate the erythrocyte mutation characteristics (MN→MO, MM, NO, NN) and give out the variant frequency. Results: 1Wa, 1Wb and 2Wa methods of GPA assay were developed. Erythrocytes of MN type individuals could be separated to normal and single locus variant groups by 1W methods and they could be sorted as normal (MN), single gene deletion mutants (MO, NO), homozygous mutants (MM, NN) cell groups by 2Wa method. Conclusion: The assay is applicable to evaluating the frequency of variant erythrocytes from human somatic mutation

Response to selection in finite locus models with nonadditive effects

NARCIS (Netherlands)

Esfandyari, Hadi; Henryon, Mark; Berg, Peer; Thomasen, Jørn Rind; Bijma, Piter; Sørensen, Anders Christian

2017-01-01

Under the finite-locus model in the absence of mutation, the additive genetic variation is expected to decrease when directional selection is acting on a population, according to quantitative-genetic theory. However, some theoretical studies of selection suggest that the level of additive

Analysis of time of death of prenatally lethal Steeloid mutations

International Nuclear Information System (INIS)

Rinchik, E.M.; Cummings, C.C.; Bangham, J.W.; Hunsicker, P.R.; Phipps, E.L.; Stelzner, K.F.

1987-01-01

Deletion mutations have been extremely useful in initiating the functional and molecular dissections of regions of the mouse genome. For the d-se and c regions, for example, it was observed that radiation mutations carrying lethal factors separable, by complementation analysis, from the primary d, se, or c mutation itself, could often be associated at both the genetic and molecular levels with multilocus chromosomal deletions. Since many of the Oak Ridge Sld mutations arose in radiation mutagenesis experiments, a substantial number may carry chromosomal deletions that involve the Sl locus in chromosome 10. Because of the great value of deletion mutations for the genetic and molecular analysis of chromosomal regions and complex genetic loci, they have initiated a series of experiments designed to test whether radiation-induced Sld mutations carry other lethal factors, in addition to the lethality caused by severe alleles of the Sl locus itself, as one prescreen for identifying Sld's that are caused by deletions

Dynamic of Mutational Events in Variable Number Tandem Repeats of Escherichia coli O157:H7

Directory of Open Access Journals (Sweden)

A. V. Bustamante

2013-01-01

Full Text Available VNTRs regions have been successfully used for bacterial subtyping; however, the hypervariability in VNTR loci is problematic when trying to predict the relationships among isolates. Since few studies have examined the mutation rate of these markers, our aim was to estimate mutation rates of VNTRs specific for verotoxigenic E. coli O157:H7. The knowledge of VNTR mutational rates and the factors affecting them would make MLVA more effective for epidemiological or microbial forensic investigations. For this purpose, we analyzed nine loci performing parallel, serial passage experiments (PSPEs on 9 O157:H7 strains. The combined 9 PSPE population rates for the 8 mutating loci ranged from 4.4 × 10−05 to 1.8 × 10−03 mutations/generation, and the combined 8-loci mutation rate was of 2.5 × 10−03 mutations/generation. Mutations involved complete repeat units, with only one point mutation detected. A similar proportion between single and multiple repeat changes was detected. Of the 56 repeat mutations, 59% were insertions and 41% were deletions, and 72% of the mutation events corresponded to O157-10 locus. For alleles with up to 13 UR, a constant and low mutation rate was observed; meanwhile longer alleles were associated with higher and variable mutation rates. Our results are useful to interpret data from microevolution and population epidemiology studies and particularly point out that the inclusion or not of O157-10 locus or, alternatively, a differential weighting data according to the mutation rates of loci must be evaluated in relation with the objectives of the proposed study.

Genetic analysis of the claret locus of Drosophila melanogaster

International Nuclear Information System (INIS)

Sequeira, W.; Nelson, C.R.; Szauter, P.

1989-01-01

The claret (ca) locus of Drosophila melanogaster comprises two separately mutable domains, one responsible for eye color and one responsible for proper disjunction of chromosomes in meiosis and early cleavage divisions. Previously isolated alleles are of three types: (1) alleles of the claret (ca) type that affect eye color only, (2) alleles of the claret-nondisjunctional (ca nd ) type that affect eye color and chromosome behavior, and (3) a meiotic mutation, non-claret disjunctional (ncd), that affects chromosome behavior only. In order to investigate the genetic structure of the claret locus, the authors have isolated 19 radiation-induced alleles of claret on the basis of the eye color phenotype. Two of these 19 new alleles are of the ca nd type, while 17 are of the ca type, demonstrating that the two domains do not often act as a single target for mutagenesis. This suggests that the two separately mutable functions are likely to be encoded by separate or overlapping genes rather than by a single gene. One of the new alleles of the ca nd type is a chromosome rearrangement with a breakpoint at the position of the claret locus. If this breakpoint is the cause of the mutant phenotype and there are no other mutations associated with the rearrangement, the two functions must be encoded by overlapping genes

The influence of DNA degradation in formalin-fixed, paraffin-embedded (FFPE) tissue on locus-specific methylation assessment by MS-HRM.

Science.gov (United States)

Daugaard, Iben; Kjeldsen, Tina E; Hager, Henrik; Hansen, Lise Lotte; Wojdacz, Tomasz K

2015-12-01

Readily accessible formalin-fixed paraffin embedded (FFPE) tissues are a highly valuable source of genetic material for molecular analyses in both research and in vitro diagnostics but frequently genetic material in those samples is highly degraded. With locus-specific methylation changes being widely investigated for use as biomarkers in various aspects of clinical disease management, we aimed to evaluate to what extent standard laboratory procedures can approximate the quality of the DNA extracted from FFPE samples prior to methylation analyses. DNA quality in 107 FFPE non-small cell lung cancer (NSCLC) samples was evaluated using spectrophotometry and gel electrophoresis. Subsequently, the quality assessment results were correlated with the results of locus specific methylation assessment with methylation sensitive high resolution melting (MS-HRM). The correlation of template quality with PCR amplification performance and HRM based methylation detection indicated a significant influence of DNA quality on PCR amplification but not on methylation assessment. In conclusion, standard laboratory procedures fairly well approximate DNA degradation of FFPE samples and DNA degradation does not seem to considerably affect locus-specific methylation assessment by MS-HRM. Copyright © 2015 Elsevier Inc. All rights reserved.

Mutability of the self-incompatibility locus and identification of the S-bearing chromosome in Nicotiana alata

International Nuclear Information System (INIS)

Gastel, A.J.G. van.

1976-01-01

γ rays, X rays, fast neutrons and ethyl methanesulfonate (EMS) were used for inducing mutations at the self-incompatibility locus of Nicotiana alata. Chronic gamma irradiation and EMS treatment neither induced self-compatability mutations nor led to changes from one S allele to another. X rays and fast neutrons induced many self-compatibility mutations, but did not generate new self-incompatibility alleles. (Auth.)

Intrachromosomal amplification, locus deletion and point mutation in the aquaglyceroporin AQP1 gene in antimony resistant Leishmania (Viannia guyanensis.

Directory of Open Access Journals (Sweden)

Rubens Monte-Neto

2015-02-01

Full Text Available Antimony resistance complicates the treatment of infections caused by the parasite Leishmania.Using next generation sequencing, we sequenced the genome of four independent Leishmania guyanensis antimony-resistant (SbR mutants and found different chromosomal alterations including aneuploidy, intrachromosomal gene amplification and gene deletion. A segment covering 30 genes on chromosome 19 was amplified intrachromosomally in three of the four mutants. The gene coding for the multidrug resistance associated protein A involved in antimony resistance was also amplified in the four mutants, most likely through chromosomal translocation. All mutants also displayed a reduced accumulation of antimony mainly due to genomic alterations at the level of the subtelomeric region of chromosome 31 harboring the gene coding for the aquaglyceroporin 1 (LgAQP1. Resistance involved the loss of LgAQP1 through subtelomeric deletions in three mutants. Interestingly, the fourth mutant harbored a single G133D point mutation in LgAQP1 whose role in resistance was functionality confirmed through drug sensitivity and antimony accumulation assays. In contrast to the Leishmania subspecies that resort to extrachromosomal amplification, the Viannia strains studied here used intrachromosomal amplification and locus deletion.This is the first report of a naturally occurred point mutation in AQP1 in antimony resistant parasites.

Identification of a novel frameshift mutation in the ILDR1 gene in a UAE family, mutations review and phenotype genotype correlation.

Directory of Open Access Journals (Sweden)

Abdelaziz Tlili

Full Text Available Autosomal recessive non-syndromic hearing loss is one of the most common monogenic diseases. It is characterized by high allelic and locus heterogeneities that make a precise diagnosis difficult. In this study, whole-exome sequencing was performed for an affected patient allowing us to identify a new frameshift mutation (c.804delG in the Immunoglobulin-Like Domain containing Receptor-1 (ILDR1 gene. Direct Sanger sequencing and segregation analysis were performed for the family pedigree. The mutation was homozygous in all affected siblings but heterozygous in the normal consanguineous parents. The present study reports a first ILDR1 gene mutation in the UAE population and confirms that the whole-exome sequencing approach is a robust tool for the diagnosis of monogenic diseases with high levels of allelic and locus heterogeneity. In addition, by reviewing all reported ILDR1 mutations, we attempt to establish a genotype phenotype correlation to explain the phenotypic variability observed at low frequencies.

Diploid yeast cells yield homozygous spontaneous mutations

Science.gov (United States)

Esposito, M. S.; Bruschi, C. V.; Brushi, C. V. (Principal Investigator)

1993-01-01

A leucine-requiring hybrid of Saccharomyces cerevisiae, homoallelic at the LEU1 locus (leu1-12/leu1-12) and heterozygous for three chromosome-VII genetic markers distal to the LEU1 locus, was employed to inquire: (1) whether spontaneous gene mutation and mitotic segregation of heterozygous markers occur in positive nonrandom association and (2) whether homozygous LEU1/LEU1 mutant diploids are generated. The results demonstrate that gene mutation of leu1-12 to LEU1 and mitotic segregation of heterozygous chromosome-VII markers occur in strong positive nonrandom association, suggesting that the stimulatory DNA lesion is both mutagenic and recombinogenic. In addition, genetic analysis of diploid Leu+ revertants revealed that approximately 3% of mutations of leu1-12 to LEU1 result in LEU1/LEU1 homozygotes. Red-white sectored Leu+ colonies exhibit genotypes that implicate post-replicational chromatid breakage and exchange near the site of leu1-12 reversion, chromosome loss, and subsequent restitution of diploidy, in the sequence of events leading to mutational homozygosis. By analogy, diploid cell populations can yield variants homozygous for novel recessive gene mutations at biologically significant rates. Mutational homozygosis may be relevant to both carcinogenesis and the evolution of asexual diploid organisms.

The TREAT-NMD DMD Global Database: Analysis of More than 7,000 Duchenne Muscular Dystrophy Mutations

Science.gov (United States)

Bladen, Catherine L; Salgado, David; Monges, Soledad; Foncuberta, Maria E; Kekou, Kyriaki; Kosma, Konstantina; Dawkins, Hugh; Lamont, Leanne; Roy, Anna J; Chamova, Teodora; Guergueltcheva, Velina; Chan, Sophelia; Korngut, Lawrence; Campbell, Craig; Dai, Yi; Wang, Jen; Barišić, Nina; Brabec, Petr; Lahdetie, Jaana; Walter, Maggie C; Schreiber-Katz, Olivia; Karcagi, Veronika; Garami, Marta; Viswanathan, Venkatarman; Bayat, Farhad; Buccella, Filippo; Kimura, En; Koeks, Zaïda; van den Bergen, Janneke C; Rodrigues, Miriam; Roxburgh, Richard; Lusakowska, Anna; Kostera-Pruszczyk, Anna; Zimowski, Janusz; Santos, Rosário; Neagu, Elena; Artemieva, Svetlana; Rasic, Vedrana Milic; Vojinovic, Dina; Posada, Manuel; Bloetzer, Clemens; Jeannet, Pierre-Yves; Joncourt, Franziska; Díaz-Manera, Jordi; Gallardo, Eduard; Karaduman, A Ayşe; Topaloğlu, Haluk; El Sherif, Rasha; Stringer, Angela; Shatillo, Andriy V; Martin, Ann S; Peay, Holly L; Bellgard, Matthew I; Kirschner, Jan; Flanigan, Kevin M; Straub, Volker; Bushby, Kate; Verschuuren, Jan; Aartsma-Rus, Annemieke; Béroud, Christophe; Lochmüller, Hanns

2015-01-01

Analyzing the type and frequency of patient-specific mutations that give rise to Duchenne muscular dystrophy (DMD) is an invaluable tool for diagnostics, basic scientific research, trial planning, and improved clinical care. Locus-specific databases allow for the collection, organization, storage, and analysis of genetic variants of disease. Here, we describe the development and analysis of the TREAT-NMD DMD Global database (http://umd.be/TREAT_DMD/). We analyzed genetic data for 7,149 DMD mutations held within the database. A total of 5,682 large mutations were observed (80% of total mutations), of which 4,894 (86%) were deletions (1 exon or larger) and 784 (14%) were duplications (1 exon or larger). There were 1,445 small mutations (smaller than 1 exon, 20% of all mutations), of which 358 (25%) were small deletions and 132 (9%) small insertions and 199 (14%) affected the splice sites. Point mutations totalled 756 (52% of small mutations) with 726 (50%) nonsense mutations and 30 (2%) missense mutations. Finally, 22 (0.3%) mid-intronic mutations were observed. In addition, mutations were identified within the database that would potentially benefit from novel genetic therapies for DMD including stop codon read-through therapies (10% of total mutations) and exon skipping therapy (80% of deletions and 55% of total mutations). PMID:25604253

Reduced secreted clusterin as a mechanism for Alzheimer-associated CLU mutations

NARCIS (Netherlands)

Bettens, Karolien; Vermeulen, Steven; Van Cauwenberghe, Caroline; Heeman, Bavo; Asselbergh, Bob; Robberecht, Caroline; Engelborghs, Sebastiaan; Vandenbulcke, Mathieu; Vandenberghe, Rik; De Deyn, Peter Paul; Cruts, Marc; Van Broeckhoven, Christine; Sleegers, Kristel

2015-01-01

Background: The clusterin (CLU) gene has been identified as an important risk locus for Alzheimer's disease (AD). Although the actual risk-increasing polymorphisms at this locus remain to be identified, we previously observed an increased frequency of rare non-synonymous mutations and small

Highly parallel and short-acting amplification with locus-specific primers to detect single nucleotide polymorphisms by the DigiTag2 assay.

Directory of Open Access Journals (Sweden)

Nao Nishida

Full Text Available The DigiTag2 assay enables analysis of a set of 96 SNPs using Kapa 2GFast HotStart DNA polymerase with a new protocol that has a total running time of about 7 hours, which is 6 hours shorter than the previous protocol. Quality parameters (conversion rate, call rate, reproducibility and concordance were at the same levels as when genotype calls were acquired using the previous protocol. Multiplex PCR with 192 pairs of locus-specific primers was available for target preparation in the DigiTag2 assay without the optimization of reaction conditions, and quality parameters had the same levels as those acquired with 96-plex PCR. The locus-specific primers were able to achieve sufficient (concentration of target amplicon ≥5 nM and specific (concentration of unexpected amplicons <2 nM amplification within 2 hours, were also able to achieve detectable amplifications even when working in a 96-plex or 192-plex form. The improved DigiTag2 assay will be an efficient platform for screening an intermediate number of SNPs (tens to hundreds of sites in the replication analysis after genome-wide association study. Moreover, highly parallel and short-acting amplification with locus-specific primers may thus facilitate widespread application to other PCR-based assays.

Bystander effect-induced mutagenicity in HPRT locus of CHO cells following BNCT neutron irradiation: Characteristics of point mutations by sequence analysis

Energy Technology Data Exchange (ETDEWEB)

Kinashi, Yuko [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka (Japan)], E-mail: kinashi@rri.kyoto-u.ac.jp; Suzuki, Minoru; Masunaga, Shinichiro; Ono, Koji [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka (Japan)

2009-07-15

To investigate bystander mutagenic effects induced by alpha particles during boron neutron capture therapy (BNCT), we mixed cells that were electroporated with borocaptate sodium (BSH), which led to the accumulation of {sup 10}B inside the cells, with cells that did not contain the boron compound. BSH-containing cells were irradiated with {alpha} particles produced by the {sup 10}B(n,{alpha}){sup 7}Li reaction, whereas cells without boron were only affected by the {sup 1}H(n,{gamma}){sup 2}H and {sup 14}N(n,{rho}){sup 14}C reactions. The frequency of mutations induced in the hypoxanthine-guanine phosphoribosyltransferase (HPRT) locus was examined in Chinese hamster ovary (CHO) cells irradiated with neutrons (Kyoto University Research Reactor: 5 MW). Neutron irradiation of 1:1 mixtures of cells with and without BSH resulted in a survival fraction of 0.1, and the cells that did not contain BSH made up 99.4% of the surviving cell population. Using multiplex polymerase chain reactions (PCRs), molecular structural analysis indicated that most of the mutations induced by the bystander effect were point mutations and that the frequencies of total and partial deletions induced by the bystander effect were lower than those resulting from the {alpha} particles produced by the {sup 10}B(n,{alpha}){sup 7}Li reaction or the neutron beam from the {sup 1}H(n,{gamma}){sup 2}H and {sup 14}N(n,{rho}){sup 14}C reactions. The types of point mutations induced by the BNCT bystander effect were analyzed by cloning and sequencing methods. These mutations were comprised of 65.5% base substitutions, 27.5% deletions, and 7.0% insertions. Sequence analysis of base substitutions showed that transversions and transitions occurred in 64.7% and 35.3% of cases, respectively. G:C{yields}T:A transversion induced by 8-oxo-guanine in DNA occurred in 5.9% of base substitution mutants in the BNCT bystander group. The characteristic mutations seen in this group, induced by BNCT {alpha} particles

Prognostic implications of mutation-specific QTc standard deviation in congenital long QT syndrome.

Science.gov (United States)

Mathias, Andrew; Moss, Arthur J; Lopes, Coeli M; Barsheshet, Alon; McNitt, Scott; Zareba, Wojciech; Robinson, Jennifer L; Locati, Emanuela H; Ackerman, Michael J; Benhorin, Jesaia; Kaufman, Elizabeth S; Platonov, Pyotr G; Qi, Ming; Shimizu, Wataru; Towbin, Jeffrey A; Michael Vincent, G; Wilde, Arthur A M; Zhang, Li; Goldenberg, Ilan

2013-05-01

Individual corrected QT interval (QTc) may vary widely among carriers of the same long QT syndrome (LQTS) mutation. Currently, neither the mechanism nor the implications of this variable penetrance are well understood. To hypothesize that the assessment of QTc variance in patients with congenital LQTS who carry the same mutation provides incremental prognostic information on the patient-specific QTc. The study population comprised 1206 patients with LQTS with 95 different mutations and ≥ 5 individuals who carry the same mutation. Multivariate Cox proportional hazards regression analysis was used to assess the effect of mutation-specific standard deviation of QTc (QTcSD) on the risk of cardiac events (comprising syncope, aborted cardiac arrest, and sudden cardiac death) from birth through age 40 years in the total population and by genotype. Assessment of mutation-specific QTcSD showed large differences among carriers of the same mutations (median QTcSD 45 ms). Multivariate analysis showed that each 20 ms increment in QTcSD was associated with a significant 33% (P = .002) increase in the risk of cardiac events after adjustment for the patient-specific QTc duration and the family effect on QTc. The risk associated with QTcSD was pronounced among patients with long QT syndrome type 1 (hazard ratio 1.55 per 20 ms increment; P<.001), whereas among patients with long QT syndrome type 2, the risk associated with QTcSD was not statistically significant (hazard ratio 0.99; P = .95; P value for QTcSD-by-genotype interaction = .002). Our findings suggest that mutations with a wider variation in QTc duration are associated with increased risk of cardiac events. These findings appear to be genotype-specific, with a pronounced effect among patients with the long QT syndrome type 1 genotype. Copyright © 2013. Published by Elsevier Inc.

KITLG Mutations Cause Familial Progressive Hyper- and Hypopigmentation

DEFF Research Database (Denmark)

Amyere, Mustapha; Vogt, Thomas; Hoo, Joe

2011-01-01

by familial café-au-lait spots and skin fold freckling, caused by mutations in SPRED1. We performed a genome-wide linkage analysis in seven families with FPHH, and identified linkage on 12q21.12-q22, which overlaps with the DUH2 locus. We investigated whether KITLG in the locus is mutated in FPHH. We......Familial progressive hyper- and hypopigmentation (FPHH) is thought to be an autosomal dominant disorder with reduced penetrance. Clinical signs consist of progressive diffuse, partly blotchy hyperpigmented lesions, multiple café-au-lait spots, intermingled with scattered hypopigmented......-strand in KITLG, suggesting its important role in the activation of the KITLG receptor c-Kit. In aggregate, mutations in a single gene cause various pigmentation disorders: FPH, FPHH, and likely DUH2. Therefore, KITLG is an important modulator of skin pigmentation.Journal of Investigative Dermatology advance...

Efficient introduction of specific homozygous and heterozygous mutations using CRISPR/Cas9.

Science.gov (United States)

Paquet, Dominik; Kwart, Dylan; Chen, Antonia; Sproul, Andrew; Jacob, Samson; Teo, Shaun; Olsen, Kimberly Moore; Gregg, Andrew; Noggle, Scott; Tessier-Lavigne, Marc

2016-05-05

The bacterial CRISPR/Cas9 system allows sequence-specific gene editing in many organisms and holds promise as a tool to generate models of human diseases, for example, in human pluripotent stem cells. CRISPR/Cas9 introduces targeted double-stranded breaks (DSBs) with high efficiency, which are typically repaired by non-homologous end-joining (NHEJ) resulting in nonspecific insertions, deletions or other mutations (indels). DSBs may also be repaired by homology-directed repair (HDR) using a DNA repair template, such as an introduced single-stranded oligo DNA nucleotide (ssODN), allowing knock-in of specific mutations. Although CRISPR/Cas9 is used extensively to engineer gene knockouts through NHEJ, editing by HDR remains inefficient and can be corrupted by additional indels, preventing its widespread use for modelling genetic disorders through introducing disease-associated mutations. Furthermore, targeted mutational knock-in at single alleles to model diseases caused by heterozygous mutations has not been reported. Here we describe a CRISPR/Cas9-based genome-editing framework that allows selective introduction of mono- and bi-allelic sequence changes with high efficiency and accuracy. We show that HDR accuracy is increased dramatically by incorporating silent CRISPR/Cas-blocking mutations along with pathogenic mutations, and establish a method termed 'CORRECT' for scarless genome editing. By characterizing and exploiting a stereotyped inverse relationship between a mutation's incorporation rate and its distance to the DSB, we achieve predictable control of zygosity. Homozygous introduction requires a guide RNA targeting close to the intended mutation, whereas heterozygous introduction can be accomplished by distance-dependent suboptimal mutation incorporation or by use of mixed repair templates. Using this approach, we generated human induced pluripotent stem cells with heterozygous and homozygous dominant early onset Alzheimer's disease-causing mutations in

A novel locus for dilated cardiomyopathy maps to canine chromosome 8.

Science.gov (United States)

Werner, Petra; Raducha, Michael G; Prociuk, Ulana; Sleeper, Meg M; Van Winkle, Thomas J; Henthorn, Paula S

2008-06-01

Dilated cardiomyopathy (DCM), the most common form of cardiomyopathy, often leads to heart failure and sudden death. While a substantial proportion of DCMs are inherited, mutations responsible for the majority of DCMs remain unidentified. A genome-wide linkage study was performed to identify the locus responsible for an autosomal recessive inherited form of juvenile DCM (JDCM) in Portuguese water dogs using 16 families segregating the disease. Results link the JDCM locus to canine chromosome 8 with two-point and multipoint lod scores of 10.8 and 14, respectively. The locus maps to a 3.9-Mb region, with complete syntenic homology to human chromosome 14, that contains no genes or loci known to be involved in the development of any type of cardiomyopathy. This discovery of a DCM locus with a previously unknown etiology will provide a new gene to examine in human DCM patients and a model for testing therapeutic approaches for heart failure.

Electrostatic potentials of the S-locus F-box proteins contribute to the pollen S specificity in self-incompatibility in Petunia hybrida.

Science.gov (United States)

Li, Junhui; Zhang, Yue; Song, Yanzhai; Zhang, Hui; Fan, Jiangbo; Li, Qun; Zhang, Dongfen; Xue, Yongbiao

2017-01-01

Self-incompatibility (SI) is a self/non-self discrimination system found widely in angiosperms and, in many species, is controlled by a single polymorphic S-locus. In the Solanaceae, Rosaceae and Plantaginaceae, the S-locus encodes a single S-RNase and a cluster of S-locus F-box (SLF) proteins to control the pistil and pollen expression of SI, respectively. Previous studies have shown that their cytosolic interactions determine their recognition specificity, but the physical force between their interactions remains unclear. In this study, we show that the electrostatic potentials of SLF contribute to the pollen S specificity through a physical mechanism of 'like charges repel and unlike charges attract' between SLFs and S-RNases in Petunia hybrida. Strikingly, the alteration of a single C-terminal amino acid of SLF reversed its surface electrostatic potentials and subsequently the pollen S specificity. Collectively, our results reveal that the electrostatic potentials act as a major physical force between cytosolic SLFs and S-RNases, providing a mechanistic insight into the self/non-self discrimination between cytosolic proteins in angiosperms. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

Locus-Specific Databases and Recommendations to Strengthen Their Contribution to the Classification of Variants in Cancer Susceptibility Genes

NARCIS (Netherlands)

Greenblatt, Marc S.; Brody, Lawrence C.; Foulkes, William D.; Genuardi, Maurizio; Hofstra, Robert M. W.; Olivier, Magali; Plon, Sharon E.; Sijmons, Rolf H.; Sinilnikova, Olga; Spurdle, Amanda B.

2008-01-01

Locus-specific databases (LSDBs) are curated collections of sequence variants in genes associated with disease. LSDBs of cancer-related genes often serve as a critical resource to researchers, diagnostic laboratories, clinicians, and others in the cancer genetics community. LSDBs are poised to play

Heart-specific expression of laminopathic mutations in transgenic zebrafish.

Science.gov (United States)

Verma, Ajay D; Parnaik, Veena K

2017-07-01

Lamins are key determinants of nuclear organization and function in the metazoan nucleus. Mutations in human lamin A cause a spectrum of genetic diseases that affect cardiac muscle and skeletal muscle as well as other tissues. A few laminopathies have been modeled using the mouse. As zebrafish is a well established model for the study of cardiac development and disease, we have investigated the effects of heart-specific lamin A mutations in transgenic zebrafish. We have developed transgenic lines of zebrafish expressing conserved lamin A mutations that cause cardiac dysfunction in humans. Expression of zlamin A mutations Q291P and M368K in the heart was driven by the zebrafish cardiac troponin T2 promoter. Homozygous mutant embryos displayed nuclear abnormalities in cardiomyocyte nuclei. Expression analysis showed the upregulation of genes involved in heart regeneration in transgenic mutant embryos and a cell proliferation marker was increased in adult heart tissue. At the physiological level, there was deviation of up to 20% from normal heart rate in transgenic embryos expressing mutant lamins. Adult homozygous zebrafish were fertile and did not show signs of early mortality. Our results suggest that transgenic zebrafish models of heart-specific laminopathies show cardiac regeneration and moderate deviations in heart rate during embryonic development. © 2017 International Federation for Cell Biology.

Detection of MPL mutations by a novel allele-specific PCR-based strategy.

Science.gov (United States)

Furtado, Larissa V; Weigelin, Helmut C; Elenitoba-Johnson, Kojo S J; Betz, Bryan L

2013-11-01

MPL mutation testing is recommended in patients with suspected primary myelofibrosis or essential thrombocythemia who lack the JAK2 V617F mutation. MPL mutations can occur at allelic levels below 15%, which may escape detection by commonly used mutation screening methods such as Sanger sequencing. We developed a novel multiplexed allele-specific PCR assay capable of detecting most recurrent MPL exon 10 mutations associated with primary myelofibrosis and essential thrombocythemia (W515L, W515K, W515A, and S505N) down to a sensitivity of 2.5% mutant allele. Test results were reviewed from 15 reference cases and 1380 consecutive specimens referred to our laboratory for testing. Assay performance was compared to Sanger sequencing across a series of 58 specimens with MPL mutations. Positive cases consisted of 45 with W515L, 6 with S505N, 5 with W515K, 1 with W515A, and 1 with both W515L and S505N. Seven cases had mutations below 5% that were undetected by Sanger sequencing. Ten additional cases had mutation levels between 5% and 15% that were not consistently detected by sequencing. All results were easily interpreted in the allele-specific test. This assay offers a sensitive and reliable solution for MPL mutation testing. Sanger sequencing appears insufficiently sensitive for robust MPL mutation detection. Our data also suggest the relative frequency of S505N mutations may be underestimated, highlighting the necessity for inclusion of this mutation in MPL test platforms. Copyright © 2013 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Neutron-induced mutation experiments. Progress report, March 1, 1977--February 28, 1978

International Nuclear Information System (INIS)

Abrahamson, S.

1977-11-01

Experiments have been carried out to study the relative mutagenic effectiveness for Drosophila female germ cells of neutrons of different energies employing X-linked recessive lethal and specific locus mutation tests. The energies and doses employed to date to study X-linked lethals are 0.43 MeV (500, 1000, 1500, 1900 R (in progress)), 0.68 MeV (250, 500, 1000, 1500 R), 2 MeV (250, 500, 1000, 1500, 2000 R), 6 MeV (250, 500, 1500, 3000 R) and 15 MeV (250, 500, 1000, 1500, 3000 R). 0.43-MeV neutrons appear to have an RBE in the range 1.9 to 4.7, 0.68 MeV 2.8 to 4.3, 2 MeV (incomplete data), 6 MeV 1.7 to 3.2, and 15 MeV 1.7 to 2.2. The data for 0.43-MeV and 0.68-MeV neutrons do not yet differentiate between a linear and a quadratic dose/frequency response curve for the doses studied, but suggest a quadratic relationship. The data for 2, 6 and 15 MeV are inconclusive. The specific locus mutation data indicate the highest RBE for 0.68-MeV neutrons, followed by 2 and 6 MeV, respectively

MILDEW LOCUS O Mutation Does Not Affect Resistance to Grain Infections with Fusarium spp. and Ramularia collo-cygni.

Science.gov (United States)

Hofer, Katharina; Linkmeyer, Andrea; Textor, Katharina; Hückelhoven, Ralph; Hess, Michael

2015-09-01

MILDEW LOCUS O defines a major susceptibility gene for powdery mildew, and recessive mlo resistance alleles are widely used in breeding for powdery mildew resistance in spring barley. Barley powdery mildew resistance, which is conferred by mlo genes, is considered to be costly in terms of spontaneous defense reactions and enhanced susceptibility to cell-death-inducing pathogens. We assessed fungal infestation of barley (Hordeum vulgare) grain by measuring fungal DNA after natural infection with Fusarium spp. and Ramularia collo-cygni or after inoculation with Fusarium spp. in the field. Powdery-mildew-resistant mlo5 genotypes did not show enhanced Fusarium spp. or R. collo-cygni DNA content of grain over four consecutive years. Data add to our understanding of pleiotropic effects of mlo-mediated powdery mildew resistance and contributes to the discussion of whether or not application of barley mlo mutations may support pathogenesis of cell-death-inducing fungal pathogens under field conditions.

Sequence-indexed mutations in maize using the UniformMu transposon-tagging population

Directory of Open Access Journals (Sweden)

Baier John

2007-05-01

Full Text Available Abstract Background Gene knockouts are a critical resource for functional genomics. In Arabidopsis, comprehensive knockout collections were generated by amplifying and sequencing genomic DNA flanking insertion mutants. These Flanking Sequence Tags (FSTs map each mutant to a specific locus within the genome. In maize, FSTs have been generated using DNA transposons. Transposable elements can generate unstable insertions that are difficult to analyze for simple knockout phenotypes. Transposons can also generate somatic insertions that fail to segregate in subsequent generations. Results Transposon insertion sites from 106 UniformMu FSTs were tested for inheritance by locus-specific PCR. We confirmed 89% of the FSTs to be germinal transposon insertions. We found no evidence for somatic insertions within the 11% of insertion sites that were not confirmed. Instead, this subset of insertion sites had errors in locus-specific primer design due to incomplete or low-quality genomic sequences. The locus-specific PCR assays identified a knockout of a 6-phosphogluconate dehydrogenase gene that co-segregates with a seed mutant phenotype. The mutant phenotype linked to this knockout generates novel hypotheses about the role for the plastid-localized oxidative pentose phosphate pathway during grain-fill. Conclusion We show that FSTs from the UniformMu population identify stable, germinal insertion sites in maize. Moreover, we show that these sequence-indexed mutations can be readily used for reverse genetic analysis. We conclude from these data that the current collection of 1,882 non-redundant insertion sites from UniformMu provide a genome-wide resource for reverse genetics.

Progress in hprt mutation assay and its application in radiation biology

International Nuclear Information System (INIS)

He Jing; Li Qiang

2008-01-01

hprt gene is an X-linked locus that has been well studied and widely used as a bio-marker in mutation detection, hprt mutation assay is a gene mutation test system in mammalian cells in vitro which has been used as a biological dosimeter. In this paper, the biological characteristics of hprt gene, hprt mutation detection methodology and the application of hprt mutation assay in radiation biology are comprehensively reviewed. (authors)

Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

DEFF Research Database (Denmark)

Bojesen, Stig Egil; Pooley, Karen A; Johnatty, Sharon E

2013-01-01

TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ∼480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases...

Compound mitochondrial DNA mutations in a neurological patient ...

Indian Academy of Sciences (India)

Compound mitochondrial DNA mutations in a neurological patient with ataxia, myoclonus and deafness. Ji Hoon Park, Bo Ram Yoon, Hye Jin Kim, Phil Hyu Lee, Byung-Ok Choi and Ki Wha Chung. J. Genet. 93, 173–177. Table 1. Variations from the whole mtDNA sequence in the AMDF patient. Mutation. Report. Locus/ ...

Cystic fibrosis transmembrane conductance regulator intracellular processing, trafficking, and opportunities for mutation-specific treatment.

LENUS (Irish Health Repository)

Rogan, Mark P

2012-02-01

Recent advances in basic science have greatly expanded our understanding of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR), the chloride and bicarbonate channel that is encoded by the gene, which is mutated in patients with CF. We review the structure, function, biosynthetic processing, and intracellular trafficking of CFTR and discuss the five classes of mutations and their impact on the CF phenotype. The therapeutic discussion is focused on the significant progress toward CFTR mutation-specific therapies. We review the results of encouraging clinical trials examining orally administered therapeutics, including agents that promote read-through of class I mutations (premature termination codons); correctors, which overcome the CFTR misfolding that characterizes the common class II mutation F508del; and potentiators, which enhance the function of class III or IV mutated CFTR at the plasma membrane. Long-term outcomes from successful mutation-specific treatments could finally answer the question that has been lingering since and even before the CFTR gene discovery: Will therapies that specifically restore CFTR-mediated chloride secretion slow or arrest the deleterious cascade of events leading to chronic infection, bronchiectasis, and end-stage lung disease?

Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

NARCIS (Netherlands)

Bojesen, Stig E.; Pooley, Karen A.; Johnatty, Sharon E.; Beesley, Jonathan; Michailidou, Kyriaki; Tyrer, Jonathan P.; Edwards, Stacey L.; Pickett, Hilda A.; Shen, Howard C.; Smart, Chanel E.; Hillman, Kristine M.; Mai, Phuong L.; Lawrenson, Kate; Stutz, Michael D.; Lu, Yi; Karevan, Rod; Woods, Nicholas; Johnston, Rebecca L.; French, Juliet D.; Chen, Xiaoqing; Weischer, Maren; Nielsen, Sune F.; Maranian, Melanie J.; Ghoussaini, Maya; Ahmed, Shahana; Baynes, Caroline; Bolla, Manjeet K.; Wang, Qin; Dennis, Joe; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Healey, Sue; Lush, Michael; Tessier, Daniel C.; Vincent, Daniel; Bacot, Françis; Vergote, Ignace; Lambrechts, Sandrina; Despierre, Evelyn; Risch, Harvey A.; González-Neira, Anna; Rossing, Mary Anne; Pita, Guillermo; Doherty, Jennifer A.; Alvarez, Nuria; Larson, Melissa C.; Fridley, Brooke L.; Schoof, Nils; Chang-Claude, Jenny; Cicek, Mine S.; Peto, Julian; Kalli, Kimberly R.; Broeks, Annegien; Armasu, Sebastian M.; Schmidt, Marjanka K.; Braaf, Linde M.; Winterhoff, Boris; Nevanlinna, Heli; Konecny, Gottfried E.; Lambrechts, Diether; Rogmann, Lisa; Guénel, Pascal; Teoman, Attila; Milne, Roger L.; Garcia, Joaquin J.; Cox, Angela; Shridhar, Vijayalakshmi; Burwinkel, Barbara; Marme, Frederik; Hein, Rebecca; Sawyer, Elinor J.; Haiman, Christopher A.; Wang-Gohrke, Shan; Andrulis, Irene L.; Moysich, Kirsten B.; Hopper, John L.; Odunsi, Kunle; Lindblom, Annika; Giles, Graham G.; Brenner, Hermann; Simard, Jacques; Lurie, Galina; Fasching, Peter A.; Carney, Michael E.; Radice, Paolo; Wilkens, Lynne R.; Swerdlow, Anthony; Goodman, Marc T.; Brauch, Hiltrud; Garcia-Closas, Montserrat; Hillemanns, Peter; Winqvist, Robert; Dürst, Matthias; Devilee, Peter; Runnebaum, Ingo; Jakubowska, Anna; Lubinski, Jan; Mannermaa, Arto; Butzow, Ralf; Bogdanova, Natalia V.; Dörk, Thilo; Pelttari, Liisa M.; Zheng, Wei; Leminen, Arto; Anton-Culver, Hoda; Bunker, Clareann H.; Kristensen, Vessela; Ness, Roberta B.; Muir, Kenneth; Edwards, Robert; Meindl, Alfons; Heitz, Florian; Matsuo, Keitaro; du Bois, Andreas; Wu, Anna H.; Harter, Philipp; teo, Soo-Hwang; Schwaab, Ira; Shu, Xiao-Ou; Blot, William; Hosono, Satoyo; Kang, Daehee; Nakanishi, Toru; Hartman, Mikael; Yatabe, Yasushi; Hamann, Ute; Karlan, Beth Y.; Sangrajrang, Suleeporn; Kjaer, Susanne Krüger; Gaborieau, Valerie; Jensen, Allan; Eccles, Diana; Høgdall, Estrid; Shen, Chen-Yang; Brown, Judith; Woo, Yin Ling; Shah, Mitul; Azmi, Mat Adenan Noor; Luben, Robert; Omar, Siti Zawiah; Czene, Kamila; Vierkant, Robert A.; Nordestgaard, Børge G.; Flyger, Henrik; Vachon, Celine; Olson, Janet E.; Wang, Xianshu; Levine, Douglas A.; Rudolph, Anja; Weber, Rachel Palmieri; Flesch-Janys, Dieter; Iversen, Edwin; Nickels, Stefan; Schildkraut, Joellen M.; Silva, Isabel Dos Santos; Cramer, Daniel W.; Gibson, Lorna; Terry, Kathryn L.; Fletcher, Olivia; Vitonis, Allison F.; van der Schoot, C. Ellen; Poole, Elizabeth M.; Hogervorst, Frans B. L.; Tworoger, Shelley S.; Liu, Jianjun; Bandera, Elisa V.; Li, Jingmei; Olson, Sara H.; Humphreys, Keith; Orlow, Irene; Blomqvist, Carl; Rodriguez-Rodriguez, Lorna; Aittomäki, Kristiina; Salvesen, Helga B.; Muranen, Taru A.; Wik, Elisabeth; Brouwers, Barbara; Krakstad, Camilla; Wauters, Els; Halle, Mari K.; Wildiers, Hans; Kiemeney, Lambertus A.; Mulot, Claire; Aben, Katja K.; Laurent-Puig, Pierre; Altena, Anne Mvan; Truong, Thérèse; Massuger, Leon F. A. G.; Benitez, Javier; Pejovic, Tanja; Perez, Jose Ignacio Arias; Hoatlin, Maureen; Zamora, M. Pilar; Cook, Linda S.; Balasubramanian, Sabapathy P.; Kelemen, Linda E.; Schneeweiss, Andreas; Le, Nhu D.; Sohn, Christof; Brooks-Wilson, Angela; Tomlinson, Ian; Kerin, Michael J.; Miller, Nicola; Cybulski, Cezary; Henderson, Brian E.; Menkiszak, Janusz; Schumacher, Fredrick; Wentzensen, Nicolas; Le Marchand, Loic; Yang, Hannah P.; Mulligan, Anna Marie; Glendon, Gord; Engelholm, Svend Aage; Knight, Julia A.; Høgdall, Claus K.; Apicella, Carmel; Gore, Martin; Tsimiklis, Helen; Song, Honglin; Southey, Melissa C.; Jager, Agnes; den Ouweland, Ans M. Wvan; Brown, Robert; Martens, John W. M.; Flanagan, James M.; Kriege, Mieke; Paul, James; Margolin, Sara; Siddiqui, Nadeem; Severi, Gianluca; Whittemore, Alice S.; Baglietto, Laura; McGuire, Valerie; Stegmaier, Christa; Sieh, Weiva; Müller, Heiko; Arndt, Volker; Labrèche, France; Gao, Yu-Tang; Goldberg, Mark S.; Yang, Gong; Dumont, Martine; McLaughlin, John R.; Hartmann, Arndt; Ekici, Arif B.; Beckmann, Matthias W.; Phelan, Catherine M.; Lux, Michael P.; Permuth-Wey, Jenny; Peissel, Bernard; Sellers, Thomas A.; Ficarazzi, Filomena; Barile, Monica; Ziogas, Argyrios; Ashworth, Alan; Gentry-Maharaj, Aleksandra; Jones, Michael; Ramus, Susan J.; Orr, Nick; Menon, Usha; Pearce, Celeste L.; Brüning, Thomas; Pike, Malcolm C.; Ko, Yon-Dschun; Lissowska, Jolanta; Figueroa, Jonine; Kupryjanczyk, Jolanta; Chanock, Stephen J.; Dansonka-Mieszkowska, Agnieszka; Jukkola-Vuorinen, Arja; Rzepecka, Iwona K.; Pylkäs, Katri; Bidzinski, Mariusz; Kauppila, Saila; Hollestelle, Antoinette; Seynaeve, Caroline; Tollenaar, Rob A. E. M.; Durda, Katarzyna; Jaworska, Katarzyna; Hartikainen, Jaana M.; Kosma, Veli-Matti; Kataja, Vesa; Antonenkova, Natalia N.; Long, Jirong; Shrubsole, Martha; Deming-Halverson, Sandra; Lophatananon, Artitaya; Siriwanarangsan, Pornthep; Stewart-Brown, Sarah; Ditsch, Nina; Lichtner, Peter; Schmutzler, Rita K.; Ito, Hidemi; Iwata, Hiroji; Tajima, Kazuo; Tseng, Chiu-Chen; Stram, Daniel O.; van den Berg, David; Yip, Cheng Har; Ikram, M. Kamran; teh, Yew-Ching; Cai, Hui; Lu, Wei; Signorello, Lisa B.; Cai, Qiuyin; Noh, Dong-Young; Yoo, Keun-Young; Miao, Hui; Iau, Philip Tsau-Choong; teo, Yik Ying; McKay, James; Shapiro, Charles; Ademuyiwa, Foluso; Fountzilas, George; Hsiung, Chia-Ni; Yu, Jyh-Cherng; Hou, Ming-Feng; Healey, Catherine S.; Luccarini, Craig; Peock, Susan; Stoppa-Lyonnet, Dominique; Peterlongo, Paolo; Rebbeck, Timothy R.; Piedmonte, Marion; Singer, Christian F.; Friedman, Eitan; Thomassen, Mads; Offit, Kenneth; Hansen, Thomas V. O.; Neuhausen, Susan L.; Szabo, Csilla I.; Blanco, Ignacio; Garber, Judy; Narod, Steven A.; Weitzel, Jeffrey N.; Montagna, Marco; Olah, Edith; Godwin, Andrew K.; Yannoukakos, Drakoulis; Goldgar, David E.; Caldes, Trinidad; Imyanitov, Evgeny N.; Tihomirova, Laima; Arun, Banu K.; Campbell, Ian; Mensenkamp, Arjen R.; van Asperen, Christi J.; van Roozendaal, Kees E. P.; Meijers-Heijboer, Hanne; Collée, J. Margriet; Oosterwijk, Jan C.; Hooning, Maartje J.; Rookus, Matti A.; van der Luijt, Rob B.; Os, Theo A. Mvan; Evans, D. Gareth; Frost, Debra; Fineberg, Elena; Barwell, Julian; Walker, Lisa; Kennedy, M. John; Platte, Radka; Davidson, Rosemarie; Ellis, Steve D.; Cole, Trevor; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Damiola, Francesca; Faivre, Laurence; Frenay, Marc; Sinilnikova, Olga M.; Caron, Olivier; Giraud, Sophie; Mazoyer, Sylvie; Bonadona, Valérie; Caux-Moncoutier, Virginie; Toloczko-Grabarek, Aleksandra; Gronwald, Jacek; Byrski, Tomasz; Spurdle, Amanda B.; Bonanni, Bernardo; Zaffaroni, Daniela; Giannini, Giuseppe; Bernard, Loris; Dolcetti, Riccardo; Manoukian, Siranoush; Arnold, Norbert; Engel, Christoph; Deissler, Helmut; Rhiem, Kerstin; Niederacher, Dieter; Plendl, Hansjoerg; Sutter, Christian; Wappenschmidt, Barbara; Borg, Ake; Melin, Beatrice; Rantala, Johanna; Soller, Maria; Nathanson, Katherine L.; Domchek, Susan M.; Rodriguez, Gustavo C.; Salani, Ritu; Kaulich, Daphne Gschwantler; tea, Muy-Kheng; Paluch, Shani Shimon; Laitman, Yael; Skytte, Anne-Bine; Kruse, Torben A.; Jensen, Uffe Birk; Robson, Mark; Gerdes, Anne-Marie; Ejlertsen, Bent; Foretova, Lenka; Savage, Sharon A.; Lester, Jenny; Soucy, Penny; Kuchenbaecker, Karoline B.; Olswold, Curtis; Cunningham, Julie M.; Slager, Susan; Pankratz, Vernon S.; Dicks, Ed; Lakhani, Sunil R.; Couch, Fergus J.; Hall, Per; Monteiro, Alvaro N. A.; Gayther, Simon A.; Pharoah, Paul D. P.; Reddel, Roger R.; Goode, Ellen L.; Greene, Mark H.; Easton, Douglas F.; Berchuck, Andrew; Antoniou, Antonis C.; Chenevix-Trench, Georgia; Dunning, Alison M.

2013-01-01

TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ∼480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases and

A Gene Encoding a DUF247 Domain Protein Cosegregates with the S Self-Incompatibility Locus in Perennial Ryegrass

DEFF Research Database (Denmark)

Manzanares, Chloe; Barth, Susanne; Thorogood, Daniel

2016-01-01

genes cosegregating with the S-locus, a highly polymorphic gene encoding for a protein containing a DUF247 was fully predictive of known S-locus genotypes at the amino acid level in the seven mapping populations. Strikingly, this gene showed a frameshift mutation in self-compatible darnel (Lolium...

Search for gene mutations affecting protein structure in children of A-bomb survivors, 2

International Nuclear Information System (INIS)

Satoh, Chiyoko; Fujita, Mikio; Goriki, Kazuaki; Asakawa, Jun-ichi; Takahashi, Norio; Hamilton, H.B.; Hazama, Ryuji; Neel, J.V.

1984-01-01

Children who were born between May 1, 1946 and April 1, 1971 to survivor(s) exposed to A-bombing within 2,000 m from the hypocenter in Hiroshima and Nagasaki were selected as exposed group; their sex- and age-matched children born to survivor(s) who were exposed at 2,500 m or farther were selected as control group. When these children were in junior high school, mutation of protein structure was examined by using electrophoresis and by determining red cell enzymes with decreased activity and heat-unstable red cell enzymes. Electrophoretic study revealed a ''rare type of protein mutation'' in 635 of 12,242 individuals in the exposed group and in 448 of 10,154 individuals in the control group. The number of locuses in all proteins examined was calculated. The number of locuses per protein was corrected using the rate of parents' mutation type, and relative number of locuses were obtained. As a result, there was no difference in the mutation frequency per locus and generation between the exposed and control groups. Among children having red cell enzymes with decreased activity, mutant in triose phosphate isomerase was detected in one child in the exposed group, in whom electrophoretic pattern was normal and red cell enzymes were stable to heat. Heat-unstable red cell enzymes were seen in 9 children and their parents. However, family survey revealed genetic mutation in all instances irrespective of A-bombing. (Namekawa, K.)

TAL effector nucleases induce mutations at a pre-selected location in the genome of primary barley transformants

DEFF Research Database (Denmark)

Wendt, Toni; Holm, Preben Bach; Starker, Colby G

2013-01-01

, and their broad targeting range. Here we report the assembly of several TALENs for a specific genomic locus in barley. The cleavage activity of individual TALENs was first tested in vivo using a yeast-based, single-strand annealing assay. The most efficient TALEN was then selected for barley transformation....... Analysis of the resulting transformants showed that TALEN-induced double strand breaks led to the introduction of short deletions at the target site. Additional analysis revealed that each barley transformant contained a range of different mutations, indicating that mutations occurred independently...

Three mutations switch H7N9 influenza to human-type receptor specificity

Energy Technology Data Exchange (ETDEWEB)

de Vries, Robert P.; Peng, Wenjie; Grant, Oliver C.; Thompson, Andrew J.; Zhu, Xueyong; Bouwman, Kim M.; de la Pena, Alba T. Torrents; van Breemen, Marielle J.; Ambepitiya Wickramasinghe, Iresha N.; de Haan, Cornelis A. M.; Yu, Wenli; McBride, Ryan; Sanders, Rogier W.; Woods, Robert J.; Verheije, Monique H.; Wilson, Ian A.; Paulson, James C.; Fernandez-Sesma, Ana

2017-06-15

The avian H7N9 influenza outbreak in 2013 resulted from an unprecedented incidence of influenza transmission to humans from infected poultry. The majority of human H7N9 isolates contained a hemagglutinin (HA) mutation (Q226L) that has previously been associated with a switch in receptor specificity from avian-type (NeuAcα2-3Gal) to human-type (NeuAcα2-6Gal), as documented for the avian progenitors of the 1957 (H2N2) and 1968 (H3N2) human influenza pandemic viruses. While this raised concern that the H7N9 virus was adapting to humans, the mutation was not sufficient to switch the receptor specificity of H7N9, and has not resulted in sustained transmission in humans. To determine if the H7 HA was capable of acquiring human-type receptor specificity, we conducted mutation analyses. Remarkably, three amino acid mutations conferred a switch in specificity for human-type receptors that resembled the specificity of the 2009 human H1 pandemic virus, and promoted binding to human trachea epithelial cells.

Three mutations switch H7N9 influenza to human-type receptor specificity.

Directory of Open Access Journals (Sweden)

Robert P de Vries

2017-06-01

Full Text Available The avian H7N9 influenza outbreak in 2013 resulted from an unprecedented incidence of influenza transmission to humans from infected poultry. The majority of human H7N9 isolates contained a hemagglutinin (HA mutation (Q226L that has previously been associated with a switch in receptor specificity from avian-type (NeuAcα2-3Gal to human-type (NeuAcα2-6Gal, as documented for the avian progenitors of the 1957 (H2N2 and 1968 (H3N2 human influenza pandemic viruses. While this raised concern that the H7N9 virus was adapting to humans, the mutation was not sufficient to switch the receptor specificity of H7N9, and has not resulted in sustained transmission in humans. To determine if the H7 HA was capable of acquiring human-type receptor specificity, we conducted mutation analyses. Remarkably, three amino acid mutations conferred a switch in specificity for human-type receptors that resembled the specificity of the 2009 human H1 pandemic virus, and promoted binding to human trachea epithelial cells.

Heterotic trait locus (HTL) mapping identifies intra-locus interactions that underlie reproductive hybrid vigor in Sorghum bicolor.

Science.gov (United States)

Ben-Israel, Imri; Kilian, Benjamin; Nida, Habte; Fridman, Eyal

2012-01-01

Identifying intra-locus interactions underlying heterotic variation among whole-genome hybrids is a key to understanding mechanisms of heterosis and exploiting it for crop and livestock improvement. In this study, we present the development and first use of the heterotic trait locus (HTL) mapping approach to associate specific intra-locus interactions with an overdominant heterotic mode of inheritance in a diallel population using Sorghum bicolor as the model. This method combines the advantages of ample genetic diversity and the possibility of studying non-additive inheritance. Furthermore, this design enables dissecting the latter to identify specific intra-locus interactions. We identified three HTLs (3.5% of loci tested) with synergistic intra-locus effects on overdominant grain yield heterosis in 2 years of field trials. These loci account for 19.0% of the heterotic variation, including a significant interaction found between two of them. Moreover, analysis of one of these loci (hDPW4.1) in a consecutive F2 population confirmed a significant 21% increase in grain yield of heterozygous vs. homozygous plants in this locus. Notably, two of the three HTLs for grain yield are in synteny with previously reported overdominant quantitative trait loci for grain yield in maize. A mechanism for the reproductive heterosis found in this study is suggested, in which grain yield increase is achieved by releasing the compensatory tradeoffs between biomass and reproductive output, and between seed number and weight. These results highlight the power of analyzing a diverse set of inbreds and their hybrids for unraveling hitherto unknown allelic interactions mediating heterosis.

Mutations and Rearrangements in the Genome of Sulfolobus solfataricus P2

DEFF Research Database (Denmark)

Redder, P.; Garrett, R. A.

2006-01-01

The genome of Sulfolobus solfataricus P2 carries a larger number of transposable elements than any other sequenced genome from an archaeon or bacterium and, as a consequence, may be particularly susceptible to rearrangement and change. In order to gain more insight into the natures and frequencies...... of different types of mutation and possible rearrangements that can occur in the genome, the pyrEF locus was examined for mutations that were isolated after selection with 5-fluoroorotic acid. About two-thirds of the 130 mutations resulted from insertions of mobile elements, including insertion sequence (IS...... deletions, insertions, and a duplication, were observed, and about one-fifth of the mutations occurred elsewhere in the genome, possibly in an orotate transporter gene. One mutant exhibited a 5-kb genomic rearrangement at the pyrEF locus involving a two-step IS element-dependent reaction, and its boundaries...

Determining Y-STR mutation rates in deep-routing genealogies: Identification of haplogroup differences.

Science.gov (United States)

Claerhout, Sofie; Vandenbosch, Michiel; Nivelle, Kelly; Gruyters, Leen; Peeters, Anke; Larmuseau, Maarten H D; Decorte, Ronny

2018-05-01

Knowledge of Y-chromosomal short tandem repeat (Y-STR) mutation rates is essential to determine the most recent common ancestor (MRCA) in familial searching or genealogy research. Up to now, locus-specific mutation rates have been extensively examined especially for commercially available forensic Y-STRs, while haplogroup specific mutation rates have not yet been investigated in detail. Through 450 patrilineally related namesakes distributed over 212 deep-rooting genealogies, the individual mutation rates of 42 Y-STR loci were determined, including 27 forensic Y-STR loci from the Yfiler ® Plus kit and 15 additional Y-STR loci (DYS388, DYS426, DYS442, DYS447, DYS454, DYS455, DYS459a/b, DYS549, DYS607, DYS643, DYS724a/b and YCAIIa/b). At least 726 mutations were observed over 148,596 meiosis and individual Y-STR mutation rates varied from 2.83 × 10 -4 to 1.86 × 10 -2 . The mutation rate was significantly correlated with the average allele size, the complexity of the repeat motif sequence and the age of the father. Significant differences in average Y-STR mutations rates were observed when haplogroup 'I & J' (4.03 × 10 -3 mutations/generation) was compared to 'R1b' (5.35 × 10 -3 mutations/generation) and to the overall mutation rate (5.03 × 10 -3 mutations/generation). A difference in allele size distribution was identified as the only cause for these haplogroup specific mutation rates. The haplogroup specific mutation rates were also present within the commercially available Y-STR kits (Yfiler ® , PowerPlex ® Y23 System and Yfiler ® Plus). This observation has consequences for applications where an average Y-STR mutation rate is used, e.g. tMRCA estimations in familial searching and genealogy research. Copyright © 2018 Elsevier B.V. All rights reserved.

Radiation-induced mutation at minisatellite loci

International Nuclear Information System (INIS)

Dubrova, Y.E.; Nesterov, V.N.; Krouchinsky, N.G.

1997-01-01

We are studying the radiation-induced increase of mutation rate in minisatellite loci in mice and humans. Minisatellite mutations were scored by multilocus DNA fingerprint analysis in the progeny of γ-irradiated and non-irradiated mice. The frequency of mutation in offspring of irradiated males was 1.7 higher that in the control group. Germline mutation at human minisatellite loci was studied among children born in heavily polluted areas of the Mogilev district of Belarus after the Chernobyl accident and in a control population. The frequency of mutation assayed both by DNA fingerprinting and by eight single locus probes was found to be two times higher in the exposed families than in the control group. Furthermore, mutation rate was correlated with the parental radiation dose for chronic exposure 137 Cs, consistent with radiation-induction of germline mutation. The potential use of minisatellites in monitoring germline mutation in humans will be discussed

Search for mutations altering protein charge and/or function in children of atomic bomb survivors: final report

International Nuclear Information System (INIS)

Neel, J.V.; Satoh, Chiyoko; Goriki, Kazuaki; Asakawa, Jun-ichi; Fujita, Mikio; Takahashi, Norio; Kageoka, Takeshi; Hazama, Ryuji.

1990-04-01

A sample of children whose parents were proximally exposed at the time of the atomic bombings of Hiroshima and Nagasaki (i.e., within 2,000 m of the hypocenter) and a suitable comparison group have been examined for the occurrence of mutations altering the electrophoretic mobility or activity of a series of 30 proteins. The examination of the equivalent of 667,404 locus products in the children of proximally exposed persons yielded three mutations altering electrophoretic mobility; the corresponding figure for the comparison group was three mutations in 466,881 tests. The examination of a subset of 60,529 locus products for loss of enzyme activity in the children of proximally exposed persons yielded one mutation; no mutations were encountered in 61,741 determinations on the children of the comparison group. Combining these two series, the mutation rate observed in the children of proximally exposed is thus 0.60 x 10 -5 /locus/generation, with 95 % confidence intervals between 0.2 and 1.5 x 10 -5 , and in the comparison children, 0.64 x 10 -5 /locus/generation, with 95 % intervals between 0.1 and 1.9 x 10 -5 . The average conjoint gonad doses of the proximally exposed parents are estimated to be 0.437 Gy of gamma radiation and 0.002 Gy of neutron radiation. Assigning a relative biological effectiveness of 20 to the neutron radiation, the combined total gonad dose of the parents becomes 0.477 Sv. (author)

A site specific model and analysis of the neutral somatic mutation rate in whole-genome cancer data.

Science.gov (United States)

Bertl, Johanna; Guo, Qianyun; Juul, Malene; Besenbacher, Søren; Nielsen, Morten Muhlig; Hornshøj, Henrik; Pedersen, Jakob Skou; Hobolth, Asger

2018-04-19

Detailed modelling of the neutral mutational process in cancer cells is crucial for identifying driver mutations and understanding the mutational mechanisms that act during cancer development. The neutral mutational process is very complex: whole-genome analyses have revealed that the mutation rate differs between cancer types, between patients and along the genome depending on the genetic and epigenetic context. Therefore, methods that predict the number of different types of mutations in regions or specific genomic elements must consider local genomic explanatory variables. A major drawback of most methods is the need to average the explanatory variables across the entire region or genomic element. This procedure is particularly problematic if the explanatory variable varies dramatically in the element under consideration. To take into account the fine scale of the explanatory variables, we model the probabilities of different types of mutations for each position in the genome by multinomial logistic regression. We analyse 505 cancer genomes from 14 different cancer types and compare the performance in predicting mutation rate for both regional based models and site-specific models. We show that for 1000 randomly selected genomic positions, the site-specific model predicts the mutation rate much better than regional based models. We use a forward selection procedure to identify the most important explanatory variables. The procedure identifies site-specific conservation (phyloP), replication timing, and expression level as the best predictors for the mutation rate. Finally, our model confirms and quantifies certain well-known mutational signatures. We find that our site-specific multinomial regression model outperforms the regional based models. The possibility of including genomic variables on different scales and patient specific variables makes it a versatile framework for studying different mutational mechanisms. Our model can serve as the neutral null model

Characterisation of monotreme caseins reveals lineage-specific expansion of an ancestral casein locus in mammals.

Science.gov (United States)

Lefèvre, Christophe M; Sharp, Julie A; Nicholas, Kevin R

2009-01-01

Using a milk-cell cDNA sequencing approach we characterised milk-protein sequences from two monotreme species, platypus (Ornithorhynchus anatinus) and echidna (Tachyglossus aculeatus) and found a full set of caseins and casein variants. The genomic organisation of the platypus casein locus is compared with other mammalian genomes, including the marsupial opossum and several eutherians. Physical linkage of casein genes has been seen in the casein loci of all mammalian genomes examined and we confirm that this is also observed in platypus. However, we show that a recent duplication of beta-casein occurred in the monotreme lineage, as opposed to more ancient duplications of alpha-casein in the eutherian lineage, while marsupials possess only single copies of alpha- and beta-caseins. Despite this variability, the close proximity of the main alpha- and beta-casein genes in an inverted tail-tail orientation and the relative orientation of the more distant kappa-casein genes are similar in all mammalian genome sequences so far available. Overall, the conservation of the genomic organisation of the caseins indicates the early, pre-monotreme development of the fundamental role of caseins during lactation. In contrast, the lineage-specific gene duplications that have occurred within the casein locus of monotremes and eutherians but not marsupials, which may have lost part of the ancestral casein locus, emphasises the independent selection on milk provision strategies to the young, most likely linked to different developmental strategies. The monotremes therefore provide insight into the ancestral drivers for lactation and how these have adapted in different lineages.

Cellular and molecular effects for mutation induction in normal human cells irradiated with accelerated neon ions

International Nuclear Information System (INIS)

Suzuki, Masao; Tsuruoka, Chizuru; Kanai, Tatsuaki; Kato, Takeshi; Yatagai, Fumio; Watanabe, Masami

2006-01-01

We investigated the linear energy transfer (LET) dependence of mutation induction on the hypoxanthine-guanine phosphoribosyl transferase (HPRT) locus in normal human fibroblast-like cells irradiated with accelerated neon-ion beams. The cells were irradiated with neon-ion beams at various LETs ranging from 63 to 335 keV/μm. Neon-ion beams were accelerated by the Riken Ring Cyclotron at the Institute of Physical and Chemical Research in Japan. Mutation induction at the HPRT locus was detected to measure 6-thioguanine-resistant clones. The mutation spectrum of the deletion pattern of exons of mutants was analyzed using the multiplex polymerase chain reaction (PCR). The dose-response curves increased steeply up to 0.5 Gy and leveled off or decreased between 0.5 and 1.0 Gy, compared to the response to 137 Cs γ-rays. The mutation frequency increased up to 105 keV/μm and then there was a downward trend with increasing LET values. The deletion pattern of exons was non-specific. About 75-100% of the mutants produced using LETs ranging from 63 to 335 keV/μm showed all or partial deletions of exons, while among γ-ray-induced mutants 30% showed no deletions, 30% partial deletions and 40% complete deletions. These results suggested that the dose-response curves of neon-ion-induced mutations were dependent upon LET values, but the deletion pattern of DNA was not

Quantum dots immunofluorescence histochemical detection of EGFR gene mutations in the non-small cell lung cancers using mutation-specific antibodies

Directory of Open Access Journals (Sweden)

Qu YG

2014-12-01

Full Text Available Yan-Gang Qu,1 Qian Zhang,2 Qi Pan,3 Xian-Da Zhao,4 Yan-Hua Huang,2 Fu-Chun Chen,3 Hong-Lei Chen41Department of Pathology, The Central Hospital of Enshi Autonomous Prefecture, Enshi, 2Department of Molecular Pathology, Wuhan Nano Tumor Diagnosis Engineering Research Center, Wuhan, Hubei, People’s Republic of China; 3Department of Thoracosurgery, Traditional Chinese Medical Hospital of Wenling, Wenling, Zhejiang, People’s Republic of China; 4Department of Pathology, School of Basic Medical Science, Wuhan University, Wuhan, Hubei, People’s Republic of ChinaBackground: Epidermal growth factor receptor (EGFR mutation status plays an important role in therapeutic decision making for non-small cell lung cancer (NSCLC patients. Since EGFR mutation-specific antibodies (E746-A750del and L858R have been developed, EGFR mutation detection by immunohistochemistry (IHC is a suitable screening test. On this basis, we want to establish a new screening test, quantum dots immunofluorescence histochemistry (QDs-IHC, to assess EGFR gene mutation in NSCLC tissues, and we compared it to traditional IHC and amplification refractory mutation system (ARMS.Materials and methods: EGFR gene mutations were detected by QDs-IHC, IHC, and ADx-ARMS in 65 cases of NSCLC composed of 55 formalin-fixed, paraffin-embedded specimens and ten pleural effusion cell blocks, including 13 squamous cell carcinomas, two adenosquamous carcinomas, and 50 adenocarcinomas.Results: Positive rates of EGFR gene mutations detected by QDs-IHC, IHC, and ADx-ARMS were 40.0%, 36.9%, and 46.2%, respectively, in 65 cases of NSCLC patients. The sensitivity of QDs-IHC when detecting EGFR mutations, as compared to ADx-ARMS, was 86.7% (26/30; the specificity for both antibodies was 100.0% (26/26. IHC sensitivity was 80.0% (24/30 and the specificity was 92.31% (24/26. When detecting EGFR mutations, QDs-IHC and ADx-ARMS had perfect consistency (κ=0.882; P<0.01. Excellent agreement was observed

Refinement of the X-linked cataract locus (CXN) and gene analysis for CXN and Nance-Horan syndrome (NHS).

Science.gov (United States)

Brooks, Simon; Ebenezer, Neil; Poopalasundaram, Subathra; Maher, Eamonn; Francis, Peter; Moore, Anthony; Hardcastle, Alison

2004-06-01

The X-linked congenital cataract (CXN) locus has been mapped to a 3-cM (approximately 3.5 Mb) interval on chromosome Xp22.13, which is syntenic to the mouse cataract disease locus Xcat and encompasses the recently refined Nance-Horan syndrome (NHS) locus. A positional cloning strategy has been adopted to identify the causative gene. In an attempt to refine the CXN locus, seven microsatellites were analysed within 21 individuals of a CXN family. Haplotypes were reconstructed confirming disease segregation with markers on Xp22.13. In addition, a proximal cross-over was observed between markers S3 and S4, thereby refining the CXN disease interval by approximately 400 Kb to 3.2 Mb, flanked by markers DXS9902 and S4. Two known genes (RAI2 and RBBP7) and a novel gene (TL1) were screened for mutations within an affected male from the CXN family and an NHS family by direct sequencing of coding exons and intron- exon splice sites. No mutations or polymorphisms were identified, therefore excluding them as disease-causative in CXN and NHS. In conclusion, the CXN locus has been successfully refined and excludes PPEF1 as a candidate gene. A further three candidates were excluded based on sequence analysis. Future positional cloning efforts will focus on the region of overlap between CXN, Xcat, and NHS.

Familial Mediterranean fever, Inflammation and Nephrotic Syndrome: Fibrillary Glomerulopathy and the M680I Missense Mutation

Directory of Open Access Journals (Sweden)

Semerdjian Ronald J

2003-08-01

Full Text Available Abstract Background Familial Mediterranean fever (FMF is an autosomal recessive disease characterized by inflammatory serositis (fever, peritonitis, synovitis and pleuritis. The gene locus responsible for FMF was identified in 1992 and localized to the short arm of chromosome 16. In 1997, a specific FMF gene locus, MEFV, was discovered to encode for a protein, pyrin that mediates inflammation. To date, more than forty missense mutations are known to exist. The diversity of mutations identified has provided insight into the variability of clinical presentation and disease progression. Case Report We report an individual heterozygous for the M680I gene mutation with a clinical diagnosis of FMF using the Tel-Hashomer criteria. Subsequently, the patient developed nephrotic syndrome with biopsy-confirmed fibrillary glomerulonephritis (FGN. Further diagnostic studies were unremarkable with clinical workup negative for amyloidosis or other secondary causes of nephrotic syndrome. Discussion Individuals with FMF are at greater risk for developing nephrotic syndrome. The most serious etiology is amyloidosis (AA variant with renal involvement, ultimately progressing to end-stage renal disease. Other known renal diseases in the FMF population include IgA nephropathy, IgM nephropathy, Henoch-Schönlein purpura as well as polyarteritis nodosa. Conclusion To our knowledge, this is the first association between FMF and the M680I mutation later complicated by nephrotic syndrome and fibrillary glomerulonephritis.

Allele-Specific Chromatin Recruitment and Therapeutic Vulnerabilities of ESR1 Activating Mutations.

Science.gov (United States)

Jeselsohn, Rinath; Bergholz, Johann S; Pun, Matthew; Cornwell, MacIntosh; Liu, Weihan; Nardone, Agostina; Xiao, Tengfei; Li, Wei; Qiu, Xintao; Buchwalter, Gilles; Feiglin, Ariel; Abell-Hart, Kayley; Fei, Teng; Rao, Prakash; Long, Henry; Kwiatkowski, Nicholas; Zhang, Tinghu; Gray, Nathanael; Melchers, Diane; Houtman, Rene; Liu, X Shirley; Cohen, Ofir; Wagle, Nikhil; Winer, Eric P; Zhao, Jean; Brown, Myles

2018-02-12

Estrogen receptor α (ER) ligand-binding domain (LBD) mutations are found in a substantial number of endocrine treatment-resistant metastatic ER-positive (ER + ) breast cancers. We investigated the chromatin recruitment, transcriptional network, and genetic vulnerabilities in breast cancer models harboring the clinically relevant ER mutations. These mutants exhibit both ligand-independent functions that mimic estradiol-bound wild-type ER as well as allele-specific neomorphic properties that promote a pro-metastatic phenotype. Analysis of the genome-wide ER binding sites identified mutant ER unique recruitment mediating the allele-specific transcriptional program. Genetic screens identified genes that are essential for the ligand-independent growth driven by the mutants. These studies provide insights into the mechanism of endocrine therapy resistance engendered by ER mutations and potential therapeutic targets. Copyright © 2018 Elsevier Inc. All rights reserved.

Endogenous Locus Reporter Assays.

Science.gov (United States)

Liu, Yaping; Hermes, Jeffrey; Li, Jing; Tudor, Matthew

2018-01-01

Reporter gene assays are widely used in high-throughput screening (HTS) to identify compounds that modulate gene expression. Traditionally a reporter gene assay is built by cloning an endogenous promoter sequence or synthetic response elements in the regulatory region of a reporter gene to monitor transcriptional activity of a specific biological process (exogenous reporter assay). In contrast, an endogenous locus reporter has a reporter gene inserted in the endogenous gene locus that allows the reporter gene to be expressed under the control of the same regulatory elements as the endogenous gene, thus more accurately reflecting the changes seen in the regulation of the actual gene. In this chapter, we introduce some of the considerations behind building a reporter gene assay for high-throughput compound screening and describe the methods we have utilized to establish 1536-well format endogenous locus reporter and exogenous reporter assays for the screening of compounds that modulate Myc pathway activity.

Retroviral vectors encoding ADA regulatory locus control region provide enhanced T-cell-specific transgene expression.

Science.gov (United States)

Trinh, Alice T; Ball, Bret G; Weber, Erin; Gallaher, Timothy K; Gluzman-Poltorak, Zoya; Anderson, French; Basile, Lena A

2009-12-30

Murine retroviral vectors have been used in several hundred gene therapy clinical trials, but have fallen out of favor for a number of reasons. One issue is that gene expression from viral or internal promoters is highly variable and essentially unregulated. Moreover, with retroviral vectors, gene expression is usually silenced over time. Mammalian genes, in contrast, are characterized by highly regulated, precise levels of expression in both a temporal and a cell-specific manner. To ascertain if recapitulation of endogenous adenosine deaminase (ADA) expression can be achieved in a vector construct we created a new series of Moloney murine leukemia virus (MuLV) based retroviral vector that carry human regulatory elements including combinations of the ADA promoter, the ADA locus control region (LCR), ADA introns and human polyadenylation sequences in a self-inactivating vector backbone. A MuLV-based retroviral vector with a self-inactivating (SIN) backbone, the phosphoglycerate kinase promoter (PGK) and the enhanced green fluorescent protein (eGFP), as a reporter gene, was generated. Subsequent vectors were constructed from this basic vector by deletion or addition of certain elements. The added elements that were assessed are the human ADA promoter, human ADA locus control region (LCR), introns 7, 8, and 11 from the human ADA gene, and human growth hormone polyadenylation signal. Retroviral vector particles were produced by transient three-plasmid transfection of 293T cells. Retroviral vectors encoding eGFP were titered by transducing 293A cells, and then the proportion of GFP-positive cells was determined using fluorescence-activated cell sorting (FACS). Non T-cell and T-cell lines were transduced at a multiplicity of infection (MOI) of 0.1 and the yield of eGFP transgene expression was evaluated by FACS analysis using mean fluorescent intensity (MFI) detection. Vectors that contained the ADA LCR were preferentially expressed in T-cell lines. Further improvements

Retroviral vectors encoding ADA regulatory locus control region provide enhanced T-cell-specific transgene expression

Science.gov (United States)

2009-01-01

Background Murine retroviral vectors have been used in several hundred gene therapy clinical trials, but have fallen out of favor for a number of reasons. One issue is that gene expression from viral or internal promoters is highly variable and essentially unregulated. Moreover, with retroviral vectors, gene expression is usually silenced over time. Mammalian genes, in contrast, are characterized by highly regulated, precise levels of expression in both a temporal and a cell-specific manner. To ascertain if recapitulation of endogenous adenosine deaminase (ADA) expression can be achieved in a vector construct we created a new series of Moloney murine leukemia virus (MuLV) based retroviral vector that carry human regulatory elements including combinations of the ADA promoter, the ADA locus control region (LCR), ADA introns and human polyadenylation sequences in a self-inactivating vector backbone. Methods A MuLV-based retroviral vector with a self-inactivating (SIN) backbone, the phosphoglycerate kinase promoter (PGK) and the enhanced green fluorescent protein (eGFP), as a reporter gene, was generated. Subsequent vectors were constructed from this basic vector by deletion or addition of certain elements. The added elements that were assessed are the human ADA promoter, human ADA locus control region (LCR), introns 7, 8, and 11 from the human ADA gene, and human growth hormone polyadenylation signal. Retroviral vector particles were produced by transient three-plasmid transfection of 293T cells. Retroviral vectors encoding eGFP were titered by transducing 293A cells, and then the proportion of GFP-positive cells was determined using fluorescence-activated cell sorting (FACS). Non T-cell and T-cell lines were transduced at a multiplicity of infection (MOI) of 0.1 and the yield of eGFP transgene expression was evaluated by FACS analysis using mean fluorescent intensity (MFI) detection. Results Vectors that contained the ADA LCR were preferentially expressed in T

A genetic screen for mutations affecting embryonic development in medaka fish (Oryzias latipes).

Science.gov (United States)

Loosli, F; Köster, R W; Carl, M; Kühnlein, R; Henrich, T; Mücke, M; Krone, A; Wittbrodt, J

2000-10-01

In a pilot screen, we assayed the efficiency of ethylnitrosourea (ENU) as a chemical mutagen to induce mutations that lead to early embryonic and larval lethal phenotypes in the Japanese medaka fish, Oryzias latipes. ENU acts as a very efficient mutagen inducing mutations at high rates in germ cells. Three repeated treatments of male fish in 3 mM ENU for 1 h results in locus specific mutation rates of 1.1-1.95 x10(-3). Mutagenized males were outcrossed to wild type females and the F1 offspring was used to establish F2 families. F2 siblings were intercrossed and the F3 progeny was scored 24, 48 and 72 h after fertilization for morphological alterations affecting eye development. The presented mutant phenotypes were identified using morphological criteria and occur during early developmental stages of medaka. They are stably inherited in a Mendelian fashion. The high efficiency of ENU to induce mutations in this pilot screen indicates that chemical mutagenesis and screening for morphologically visible phenotypes in medaka fish allows the genetic analysis of specific aspects of vertebrate development complementing the screens performed in other vertebrate model systems.

Somatic mutation in peripheral blood lymphocytes among Metro Manila residents: indicator of exposure to environmental pollution

International Nuclear Information System (INIS)

Yulo-Nazarea, Teresa; Cobar, Ma. Lucia C.; Nato, Alejandro Q.; Nazarea, Apolinario D.

2001-01-01

Results of a four-year study on somatic mutation in peripheral blood lymphocytes among Metro Manila residents as an indicator of exposure to environmental pollution conducted by the Philippine Nuclear Research Institute (PNRI) is presented. The study which involves mutation indexing of 200 blood donors demonstrated very strong correlation between high levels of ambient air pollution and increase incidence of mutation at the specific gene locus in peripheral blood lymphocytes among residents of specific areas in Metro Manila. Using the PNRI adapted protocol to determine incidence of mutation at a specific gene marker, hypoxanthine guanine phosphoribosyl transferase (HGPRT), our database analysis indicated a statistically significant difference between mean mutation index of blood donors residing in an area with lower level of pollution (Las Pinas) compared to those residents living in areas with the highest estimated pollution level (Valenzuela). The results of the statistical analyses should provide regulators the direction in incorporating the data into their pollution abatement program to maximize health impact. Biomarker analysis should play a greater role in the future in the formulation of national environment policies. The temporal variation of these ''aseline data'' as the Philippine moves forward through the next several years in its industrialization program should in itself be a very valuable source of environmental policy instruments. (Author)

Canine chondrodysplasia caused by a truncating mutation in collagen-binding integrin alpha subunit 10.

Directory of Open Access Journals (Sweden)

Kaisa Kyöstilä

Full Text Available The skeletal dysplasias are disorders of the bone and cartilage tissues. Similarly to humans, several dog breeds have been reported to suffer from different types of genetic skeletal disorders. We have studied the molecular genetic background of an autosomal recessive chondrodysplasia that affects the Norwegian Elkhound and Karelian Bear Dog breeds. The affected dogs suffer from disproportionate short stature dwarfism of varying severity. Through a genome-wide approach, we mapped the chondrodysplasia locus to a 2-Mb region on canine chromosome 17 in nine affected and nine healthy Elkhounds (praw = 7.42×10(-6, pgenome-wide = 0.013. The associated locus contained a promising candidate gene, cartilage specific integrin alpha 10 (ITGA10, and mutation screening of its 30 exons revealed a nonsense mutation in exon 16 (c.2083C>T; p.Arg695* that segregated fully with the disease in both breeds (p = 2.5×10(-23. A 24% mutation carrier frequency was indicated in NEs and an 8% frequency in KBDs. The ITGA10 gene product, integrin receptor α10-subunit combines into a collagen-binding α10β1 integrin receptor, which is expressed in cartilage chondrocytes and mediates chondrocyte-matrix interactions during endochondral ossification. As a consequence of the nonsense mutation, the α10-protein was not detected in the affected cartilage tissue. The canine phenotype highlights the importance of the α10β1 integrin in bone growth, and the large animal model could be utilized to further delineate its specific functions. Finally, this study revealed a candidate gene for human chondrodysplasias and enabled the development of a genetic test for breeding purposes to eradicate the disease from the two dog breeds.

Gene-specific function prediction for non-synonymous mutations in monogenic diabetes genes.

Directory of Open Access Journals (Sweden)

Quan Li

Full Text Available The rapid progress of genomic technologies has been providing new opportunities to address the need of maturity-onset diabetes of the young (MODY molecular diagnosis. However, whether a new mutation causes MODY can be questionable. A number of in silico methods have been developed to predict functional effects of rare human mutations. The purpose of this study is to compare the performance of different bioinformatics methods in the functional prediction of nonsynonymous mutations in each MODY gene, and provides reference matrices to assist the molecular diagnosis of MODY. Our study showed that the prediction scores by different methods of the diabetes mutations were highly correlated, but were more complimentary than replacement to each other. The available in silico methods for the prediction of diabetes mutations had varied performances across different genes. Applying gene-specific thresholds defined by this study may be able to increase the performance of in silico prediction of disease-causing mutations.

Specificity of mutations induced by carbon ions in budding yeast Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Matuo, Youichirou; Nishijima, Shigehiro; Hase, Yoshihiro; Sakamoto, Ayako; Tanaka, Atsushi; Shimizu, Kikuo

2006-01-01

To investigate the nature of mutations induced by accelerated ions in eukaryotic cells, the effects of carbon-ion irradiation were compared with those of γ-ray irradiation in the budding yeast Saccharomyces cerevisiae. The mutational effect and specificity of carbon-ion beams were studied in the URA3 gene of the yeast. Our experiments showed that the carbon ions generated more than 10 times the number of mutations induced by γ-rays, and that the types of base changes induced by carbon ions include transversions (68.7%), transitions (13.7%) and deletions/insertions (17.6%). The transversions were mainly G:C → T:A, and all the transitions were G:C → A:T. In comparison with the surrounding sequence context of mutational base sites, the C residues in the 5'-AC(A/T)-3' sequence were found to be easily changed. Large deletions and duplications were not observed, whereas ion-induced mutations in Arabidopsis thaliana were mainly short deletions and rearrangements. The remarkable feature of yeast mutations induced by carbon ions was that the mutation sites were localized near the linker regions of nucleosomes, whereas mutations induced by γ-ray irradiation were located uniformly throughout the gene

Protection against radiation-induced mutations at the hprt locus by spermine and N,N double-prime-(dithiodi-2,1-ethanediyl)bis-1,3-propanediamine (WR-33278)

International Nuclear Information System (INIS)

Grdina, D.J.; Schwartz, J.L.; Shigematsu, N.

1993-06-01

The polyamine spermine and the disulfide NN double-prime-(dithiodi-2,1-ethanediyl)bis-1,3-propanediamine (WR-33278) are structurally similar agents capable of binding to DNA. WR-33278 is the disulfide moiety of the clinically studied radioprotective agent (WR-2721). Because of their structural similarities, it was of interest to characterize and compare their radioprotective properties using the endpoints of cell survival and mutation induction at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus in Chinese hamster AA8 cells. In order to facilitate both the uptake of VM-33278 into cells and the direct comparison between the protective properties of WR-33278 and spermine, these agents were electroporated into cells. Electroporation alone reduced cell survival to 75% but had no effect on hprt mutation frequency. The electroporation of either spermine or WR-33278 at concentrations greater than 0.01 mM was extremely toxic. The exposure of cells to both electroporation and irradiation gave rise to enhanced cell killing and mutation induction. Cell survival values at a radiation dose of 750 cGy were enhanced by factors of 1.3 and 1.8 following electroporation of 0.01 mM of spermine and WR-33278, respectively, 30 min prior to irradiation. Neither agent was protective at a concentration of 0.001 mM. Protection against radiation-induced hprt mutations was observed for both spermine and WR-33278 under all experimental conditions tested

A search for mutations affecting protein structure in children of proximally and distally exposed atomic bomb survivors

International Nuclear Information System (INIS)

Neel, J.V.; Satoh, Chiyoko; Hamilton, H.B.; Otake, Masanori; Goriki, Kazuaki; Kageoka, Takeshi; Fujita, Mikio; Neriishi, Shotaro; Asakawa, Jun-ichi.

1981-07-01

A total of 289,868 locus tests based on 28 different protein phenotypes, employing one-dimensional electrophoresis to detect variant proteins, has yielded one probable mutation in the offspring of 'proximally exposed' parents, who received an estimated average gonadal exposure dose of between 31 and 39 rem from the atomic bombs in Hiroshima and Nagasaki. There were no mutations in 208,196 locus tests involving children of 'distally exposed' parents, who had essentially no radiation exposure. (author)

Translocations affecting human immunoglobulin heavy chain locus

Directory of Open Access Journals (Sweden)

Sklyar I. V.

2014-03-01

Full Text Available Translocations involving human immunoglobulin heavy chain (IGH locus are implicated in different leukaemias and lymphomas, including multiple myeloma, mantle cell lymphoma, Burkitt’s lymphoma and diffuse large B cell lymphoma. We have analysed published data and identified eleven breakpoint cluster regions (bcr related to these cancers within the IgH locus. These ~1 kbp bcrs are specific for one or several types of blood cancer. Our findings could help devise PCR-based assays to detect cancer-related translocations, to identify the mechanisms of translocations and to help in the research of potential translocation partners of the immunoglobulin locus at different stages of B-cell differentiation.

Exploration of methods to localize DNA sequences missing from c-locus deletions

International Nuclear Information System (INIS)

Albritton, L.M.; Russell, L.B.; Montgomery, C.S.

1987-01-01

The authors have earlier characterized a large number of radiation-induced mutations at the c locus (on Chromosome 7) through genetic analysis, including extensive complementation tests. Based on this work, they have postulated that many of these mutations are deletions of various lengths, overlapping at c (the marker used in the mutation-rate experiments that generated the mutants). It was possible to apportion these deletions among 13 complementation groups and to fit them to a linear map of 8 functional units. Collectively, the deletions extend from a point between tp and c to one between sh-1 and Hbb, i.e., a genetic distance of from 6 to 10 cM, corresponding to at least 10 4 Kb of DNA. This year, the authors completed a pilot study designed to explore methods for finding DNA sequences that map to the region covered by the various c-deletions. The general plan was to probe DNA with clones derived from Chromosome-7-enriched libraries or with sequences known (or suspected) to reside in Chromosome 7. Three methods were explored for deriving the c-region-deficient DNA: (a) from mouse-hamster somatic-cell hydrids retaining a deleted mouse Chromosome 7, but no homologue; (b) from F 1 hybrids of M. musculus domesticus (carrying a c-locus deletion) by M. spretus; and (c) from F 1 hybrids of M. domesticus stocks carrying complementing deletions

Specificity of mutations induced by carbon ions in budding yeast Saccharomyces cerevisiae

Energy Technology Data Exchange (ETDEWEB)

Matuo, Youichirou [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871 (Japan); Nishijima, Shigehiro [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871 (Japan); Hase, Yoshihiro [Radiation-Applied Biology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Watanuki-machi 1233, Takasaki, Gunma 370-1292 (Japan); Sakamoto, Ayako [Radiation-Applied Biology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Watanuki-machi 1233, Takasaki, Gunma 370-1292 (Japan); Tanaka, Atsushi [Radiation-Applied Biology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Watanuki-machi 1233, Takasaki, Gunma 370-1292 (Japan); Shimizu, Kikuo [Radioisotope Research Center, Osaka University, Yamada-oka 2-4, Suita, Osaka 565-0871 (Japan)]. E-mail: shimizu@rirc.osaka-u.ac.jp

2006-12-01

To investigate the nature of mutations induced by accelerated ions in eukaryotic cells, the effects of carbon-ion irradiation were compared with those of {gamma}-ray irradiation in the budding yeast Saccharomyces cerevisiae. The mutational effect and specificity of carbon-ion beams were studied in the URA3 gene of the yeast. Our experiments showed that the carbon ions generated more than 10 times the number of mutations induced by {gamma}-rays, and that the types of base changes induced by carbon ions include transversions (68.7%), transitions (13.7%) and deletions/insertions (17.6%). The transversions were mainly G:C {sup {yields}} T:A, and all the transitions were G:C {sup {yields}} A:T. In comparison with the surrounding sequence context of mutational base sites, the C residues in the 5'-AC(A/T)-3' sequence were found to be easily changed. Large deletions and duplications were not observed, whereas ion-induced mutations in Arabidopsis thaliana were mainly short deletions and rearrangements. The remarkable feature of yeast mutations induced by carbon ions was that the mutation sites were localized near the linker regions of nucleosomes, whereas mutations induced by {gamma}-ray irradiation were located uniformly throughout the gene.

Two-locus linkage analysis in multiple sclerosis (MS)

Energy Technology Data Exchange (ETDEWEB)

Tienari, P.J. (National Public Health Institute, Helsinki (Finland) Univ. of Helsinki (Finland)); Terwilliger, J.D.; Ott, J. (Columbia Univ., New York (United States)); Palo, J. (Univ. of Helsinki (Finland)); Peltonen, L. (National Public Health Institute, Helsinki (Finland))

1994-01-15

One of the major challenges in genetic linkage analyses is the study of complex diseases. The authors demonstrate here the use of two-locus linkage analysis in multiple sclerosis (MS), a multifactorial disease with a complex mode of inheritance. In a set of Finnish multiplex families, they have previously found evidence for linkage between MS susceptibility and two independent loci, the myelin basic protein gene (MBP) on chromosome 18 and the HLA complex on chromosome 6. This set of families provides a unique opportunity to perform linkage analysis conditional on two loci contributing to the disease. In the two-trait-locus/two-marker-locus analysis, the presence of another disease locus is parametrized and the analysis more appropriately treats information from the unaffected family member than single-disease-locus analysis. As exemplified here in MS, the two-locus analysis can be a powerful method for investigating susceptibility loci in complex traits, best suited for analysis of specific candidate genes, or for situations in which preliminary evidence for linkage already exists or is suggested. 41 refs., 6 tabs.

Necrotic enteritis locus 1 diguanylate cyclase and phosphodiesterase (cyclic-di-GMP) gene mutation attenuates virulence in an avian necrotic enteritis isolate of Clostridium perfringens.

Science.gov (United States)

Parreira, Valeria R; Ojha, Shivani; Lepp, Dion; Mehdizadeh Gohari, Iman; Zhou, Hongzhuan; Susta, Leonardo; Gong, Jianhua; Prescott, John F

2017-09-01

Necrotic enteritis (NE) caused by netB-positive strains of Clostridium perfringens is an important disease of intensively-reared broiler chickens. It is widely controlled by antibiotic use, but this practice that has come under increasing scrutiny and alternative approaches are required. As part of the search for alternative approaches over the last decade, advances have been made in understanding its pathogenesis but much remains to be understood and applied to the control of NE. The objective of this work was to assess the effect on virulence of mutation of the cyclic-di-GMP signaling genes present on the large pathogenicity locus (NELoc-1) in the tcp-encoding conjugative virulence plasmid, pNetB. For this purpose, the diguanylate cyclase (dgc) and phosphodiesterase (pde) genes were individually insertionally inactivated and the two mutants were subsequently complemented with their respective genes. Southern blotting showed that a single gene insertion was present. Mutation of either gene resulted in almost total attenuation of the mutants to cause NE in experimentally-infected broiler chickens, which was fully restored in each case by complementation of the respective mutated gene. Production of NetB-associated cytotoxicity for Leghorn male hepatoma (LMH) cells was unaffected in mutants. We conclude that the cyclic-di-GMP signaling system is important in controlling virulence in a NE C. perfringens strain and might be a target for control of the disease. Copyright © 2017 Elsevier B.V. All rights reserved.

The use of a mutationally unstable X-chromosome in Drosophila melanogaster for mutagenicity testing

International Nuclear Information System (INIS)

Rasmuson, B.; Svahlin, H.; Rasmuson, A.; Montell, I.; Olofsson, H.

1978-01-01

Somatic eye-colour mutations in an unstable genetic system, caused by a transposable element in the white locus of the X-chromosome in Drosophila melanogaster, is suggested as an assay system for mutagenicity testing. The system is evaluated by comparison with a corresponding system in a stable X-chromosome. Its sensitivity is confirmed with X-ray and EMS treatment, and it is found to be confined to the specific segment of the X-chromosome where the transposable element is localized. (Auth.)

Detection of induced male germline mutation: Correlations and comparisons between traditional germline mutation assays, transgenic rodent assays and expanded simple tandem repeat instability assays

Energy Technology Data Exchange (ETDEWEB)

Singer, Timothy M. [Mutagenesis Section, Environmental and Occupational Toxicology Division, Safe Environments Programme, 0803A, Health Canada, Ottawa, Ont., K1A 0K9 (Canada); Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ont., K1S 5B6 (Canada); Lambert, Iain B. [Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ont., K1S 5B6 (Canada); Williams, Andrew [Biostatistics and Epidemiology Division, Safe Environments Programme, 6604B, Health Canada, Ottawa, Ont., K1A 0K9 (Canada); Douglas, George R. [Mutagenesis Section, Environmental and Occupational Toxicology Division, Safe Environments Programme, 0803A, Health Canada, Ottawa, Ont., K1A 0K9 (Canada); Yauk, Carole L. [Mutagenesis Section, Environmental and Occupational Toxicology Division, Safe Environments Programme, 0803A, Health Canada, Ottawa, Ont., K1A 0K9 (Canada)]. E-mail: carole_yauk@hc-sc.gc.ca

2006-06-25

Several rodent assays are capable of monitoring germline mutation. These include traditional assays, such as the dominant lethal (DL) assay, the morphological specific locus (SL) test and the heritable translocation (HT) assay, and two assays that have been developed more recently-the expanded simple tandem repeat (ESTR) and transgenic rodent (TGR) mutation assays. In this paper, we have compiled the limited amount of experimental data that are currently available to make conclusions regarding the comparative ability of the more recently developed assays to detect germline mutations induced by chemical and radiological agents. The data suggest that ESTR and TGR assays are generally comparable with SL in detecting germline mutagenicity induced by alkylating agents and radiation, though TGR offered less sensitivity than ESTR in some cases. The DL and HT assays detect clastogenic events and are most susceptible to mutations arising in post-spermatogonial cells, and they may not provide the best comparisons with TGR and ESTR instability. The measurement of induced ESTR instability represents a relatively sensitive method of identifying agents causing germline mutation in rodents, and may also be useful for bio-monitoring exposed individuals in the human population. Any future use of the TGR and ESTR germline mutation assays in a regulatory testing context will entail more robust and extensive characterization of assay performance. This will require substantially more data, including experiments measuring multiple endpoints, a greatly expanded database of chemical agents and a focus on characterizing stage-specific activity of mutagens in these assays, preferably by sampling epididymal sperm exposed at defined pre-meiotic, meiotic and post-meiotic stages of development.

Detection of induced male germline mutation: Correlations and comparisons between traditional germline mutation assays, transgenic rodent assays and expanded simple tandem repeat instability assays

International Nuclear Information System (INIS)

Singer, Timothy M.; Lambert, Iain B.; Williams, Andrew; Douglas, George R.; Yauk, Carole L.

2006-01-01

Several rodent assays are capable of monitoring germline mutation. These include traditional assays, such as the dominant lethal (DL) assay, the morphological specific locus (SL) test and the heritable translocation (HT) assay, and two assays that have been developed more recently-the expanded simple tandem repeat (ESTR) and transgenic rodent (TGR) mutation assays. In this paper, we have compiled the limited amount of experimental data that are currently available to make conclusions regarding the comparative ability of the more recently developed assays to detect germline mutations induced by chemical and radiological agents. The data suggest that ESTR and TGR assays are generally comparable with SL in detecting germline mutagenicity induced by alkylating agents and radiation, though TGR offered less sensitivity than ESTR in some cases. The DL and HT assays detect clastogenic events and are most susceptible to mutations arising in post-spermatogonial cells, and they may not provide the best comparisons with TGR and ESTR instability. The measurement of induced ESTR instability represents a relatively sensitive method of identifying agents causing germline mutation in rodents, and may also be useful for bio-monitoring exposed individuals in the human population. Any future use of the TGR and ESTR germline mutation assays in a regulatory testing context will entail more robust and extensive characterization of assay performance. This will require substantially more data, including experiments measuring multiple endpoints, a greatly expanded database of chemical agents and a focus on characterizing stage-specific activity of mutagens in these assays, preferably by sampling epididymal sperm exposed at defined pre-meiotic, meiotic and post-meiotic stages of development

The Effects of Locus of Control and Task Difficulty on Procrastination.

Science.gov (United States)

Janssen, Tracy; Carton, John S

1999-12-01

The authors investigated the effects of locus of control expectancies and task difficulty on procrastination. Forty-two college students were administered an academic locus of control scale and a task that was similar to a typical college homework assignment. The students were randomly assigned to 1 of 2 task difficulty levels. Although none of the results involving task difficulty was significant, several results involving locus of control were significant. Specifically, analyses revealed that students with internal locus of control expectancies tended to begin working on the assignment sooner than students with external locus of control expectancies. In addition, students with internal locus of control completed and returned the assignment sooner than students with external locus of control. The results are discussed within the context of J. B. Rotter's (1966, 1975, 1982) social learning theory.

Partial isodisomy for maternal chromosome 7 and short stature in an individual with a mutation at the COL1A2 locus

Energy Technology Data Exchange (ETDEWEB)

Spotila, L.D.; Sereda, L.; Prockop, D.J. (Jefferson Medical College, Philadelphia, PA (United States))

1992-12-01

Uniparental disomy for chromosome 7 has been described previously in two individuals with cystic fibrosis. Here, the authors describe a third case that was discovered because the proband was homozygous for a mutation in the COL1A2 gene for type I procollagen, although his mother was heterozygous and his father did not have the mutation. Phenotypically, the proband was similar to the two previously reported cases with uniparental disomy for chromosome 7, in that he was short in stature and growth retarded. Paternity was assessed with five polymorphic markers. Chromosome 7 inheritance in the proband was analyzed using 12 polymorphic markers distributed along the entire chromosome. Similar analysis of the proband's two brothers established the phase of the alleles at the various loci, assuming minimal recombination. The proband inherited only maternal alleles at five loci and was homozygous at all loci examined, except one. He was heterozygous for an RFLP at the IGBP-1 locus at 7p13-p12. The results suggest that the isodisomy was not complete because of a recombination event involving the proximal short arms of two maternal chromosomes. In addition, the phenotype of proportional dwarfism in the proband suggests imprinting of one or more growth-related genes on chromosome 7. 42 refs., 5 figs., 3 tabs.

A silent allele in the locus D5S818 contained within the PowerPlex®21 PCR Amplification Kit.

Science.gov (United States)

Chen, Ling; Tai, Yunchun; Qiu, Pingming; Du, Weian; Liu, Chao

2015-11-01

Three paternity tests cases were found with a single locus mismatch at the locus D5S818 with PowerPlex®21 PCR Amplification Kit (Promega). Forward and reverse primers were redesigned to type the samples again and to evaluate if there were alleles dropped out. The results showed the existence of a silent allele 12 in all the three families, due to a point mutation that changed cytosine to adenine at 90 nucleotides upstream from the 5' end of the AGAT repeat sequences in all the six individuals. A single locus mismatch due to a silent allele may occur in any locus using any kit. Therefore, we recommend using multiple kits to confirm the results in paternity testing cases with mismatches, especially when there is a single locus mismatch with homozygote involved. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Search for mutations altering protein charge and/or function in children of atomic bomb survivors: final report

International Nuclear Information System (INIS)

Neel, J.V.; Satoh, C.; Goriki, K.; Asakawa, J.; Fujita, M.; Takahashi, N.; Kageoka, T.; Hazama, R.

1988-01-01

A sample of (1) children whose parents had been proximally exposed (i.e., less than 2000 m from the hypocenter) at the time of the atomic bombings of Hiroshima and Nagasaki and (2) a suitable comparison group have been examined for the occurrence of mutations altering the electrophoretic mobility or activity of a series of 30 proteins. The examination of the equivalent of 667,404 locus products in the children of proximally exposed persons yielded three mutations altering electrophoretic mobility; the corresponding figure for the comparison group was three mutations in 466,881 tests. The examination of a subset of 60,529 locus products for loss of enzyme activity in the children of proximally exposed persons yielded one mutation; no mutations were encountered in 61,741 determinations on the children of the comparison group. When these two series are compared, the mutation rate observed in the children of proximally exposed persons is thus 0.60 x 10(-5)/locus/generation, with 95% confidence intervals between 0.2 and 1.5 x 10(-5), and that in the comparison children is 0.64 x 10(-5)/locus/generation, with 95% intervals between 0.1 and 1.9 x 10(-5). The average conjoint gonad doses for the proximally exposed parents are estimated to be 0.437 Gy of gamma radiation and 0.002 Gy of neutron radiation. If a relative biological effectiveness of 20 is assigned to the neutron radiation, the combined total gonad dose for the parents becomes 0.477 Sv. (Organ absorbed doses are expressed in gray [1 Gy = 100 rad]; where dose is a mixture of gamma and neutron radiation, it is necessary because of the differing relative biological effectiveness of gamma and neutron radiation to express the combined gamma-neutron gonad exposures in sieverts [1 Sv = 100 rem])

Antagonism between DNA and H3K27 methylation at the imprinted Rasgrf1 locus

DEFF Research Database (Denmark)

Lindroth, Anders M; Park, Yoon Jung; McLean, Chelsea M

2008-01-01

At the imprinted Rasgrf1 locus in mouse, a cis-acting sequence controls DNA methylation at a differentially methylated domain (DMD). While characterizing epigenetic marks over the DMD, we observed that DNA and H3K27 trimethylation are mutually exclusive, with DNA and H3K27 methylation limited...... to the paternal and maternal sequences, respectively. The mutual exclusion arises because one mark prevents placement of the other. We demonstrated this in five ways: using 5-azacytidine treatments and mutations at the endogenous locus that disrupt DNA methylation; using a transgenic model in which the maternal...

Psychometric properties of the Danish versions of headache-specific locus of control scale and headache management self-efficacy scale

DEFF Research Database (Denmark)

Hansen, Jacob Sander; Bendtsen, Lars; Jensen, Rigmor

2009-01-01

The purpose of the study is to test the cross-cultural adaptation and psychometric properties of a Danish version of the Headache-Specific Locus of Control Scale (HSLC) and the Headache Management Self-Efficacy Scale (HMSE) in a tertiary headache centre. HSLC and HMSE are headache-specific measures...... with other self-report measures concerning general distress, anxiety, depression, and health-related quality of life. Internal stability of the HSLC subscales and the HMSE were analysed using Chronbach's alpha coefficient. The psychometric properties of the Danish version of the HSLC and the HMSE were...

Characterization and genetic mapping of a Photoperiod-sensitive dwarf 1 locus in rice (Oryza sativa L.).

Science.gov (United States)

Li, Riqing; Xia, Jixing; Xu, Yiwei; Zhao, Xiucai; Liu, Yao-Guang; Chen, Yuanling

2014-01-01

Plant height is an important agronomic trait for crop architecture and yield. Most known factors determining plant height function in gibberellin or brassinosteroid biosynthesis or signal transduction. Here, we report a japonica rice (Oryza sativa ssp. japonica) dominant dwarf mutant, Photoperiod-sensitive dwarf 1 (Psd1). The Psd1 mutant showed impaired cell division and elongation, and a severe dwarf phenotype under long-day conditions, but nearly normal growth in short-day. The plant height of Psd1 mutant could not be rescued by gibberellin or brassinosteroid treatment. Genetic analysis with R1 and F2 populations determined that Psd1 phenotype was controlled by a single dominant locus. Linkage analysis with 101 tall F2 plants grown in a long-day season, which were derived from a cross between Psd1 and an indica cultivar, located Psd1 locus on chromosome 1. Further fine-mapping with 1017 tall F2 plants determined this locus on an 11.5-kb region. Sequencing analysis of this region detected a mutation site in a gene encoding a putative lipid transfer protein; the mutation produces a truncated C-terminus of the protein. This study establishes the genetic foundation for understanding the molecular mechanisms regulating plant cell division and elongation mediated by interaction between genetic and environmental factors.

Analysis of fast neutron-generated mutants at the Arabidopsis thaliana HY4 locus

International Nuclear Information System (INIS)

Bruggemann, E.; Handwerger, K.; Essex, C.; Storz, G.

1996-01-01

Ionizing radiation is expected to produce mutants with deletions or other chromosomal rearrangements. These mutants are useful for a variety of purposes, such as creating null alleles and cloning genes whose existence is known only from their mutant phenotype; however, only a few mutations generated by ionizing radiation have been characterized at the molecular level in Arabidopsis thaliana. Twenty fast neutron-generated alleles of the Arabidopsis HY4 locus, which encodes a blue light receptor, CRY1, were isolated and characterized. Nine of the mutant alleles displayed normal genetic behavior. The other 11 mutant alleles were poorly transmitted through the male gametophyte and were lethal in homozygous plants. Southern blot analysis demonstrated that alleles of the first group generally contain small or moderate-sized deletions at HY4, while alleles of the second group contain large deletions at this locus. These results demonstrate that fast neutrons can produce a range of deletions at a single locus in Arabidopsis. Many of these deletions would be suitable for cloning by genomic subtraction or representational difference analysis. The results also suggest the presence of an essential locus adjacent to HY4. (author)

Establishment of a novel monoclonal antibody SMab-1 specific for IDH1-R132S mutation

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Mika Kato; Tian, Wei [Molecular Tumor Marker Research Team, The Oncology Research Center, Advanced Molecular Epidemiology Research Institute, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Takano, Shingo [Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575 (Japan); Suzuki, Hiroyuki [Department of Experimental Pathology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575 (Japan); Sawa, Yoshihiko [Section of Functional Structure, Department of Morphological Biology, Division of Biomedical Sciences, Fukuoka Dental College, 2-15-1 Tamura, Sawara-ku, Fukuoka 814-0193 (Japan); Hozumi, Yasukazu; Goto, Kaoru [Department of Anatomy and Cell Biology, Yamagata University School of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Yamazaki, Kentaro [Department of Forensic Medicine, Yamagata University School of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Kitanaka, Chifumi [Department of Molecular Cancer Science, Yamagata University School of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Kato, Yukinari, E-mail: yukinari-k@bea.hi-ho.ne.jp [Molecular Tumor Marker Research Team, The Oncology Research Center, Advanced Molecular Epidemiology Research Institute, Yamagata University Faculty of Medicine, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan)

2011-03-25

Research highlights: {yields} IDH1 mutations are early and frequent genetic alterations in gliomas. {yields} We newly established an anti-IDH1-R132S-specific mAb SMab-1. {yields} SMab-1 reacted with the IDH1-R132S peptide, but not with other IDH1 mutants. {yields} SMab-1 specifically stained the IDH1-R132S-expressing glioblastoma cells in immunocytochemistry and immunohistochemistry. {yields} SMab-1 should be useful in diagnosis of mutation-bearing gliomas. -- Abstract: Isocitrate dehydrogenase 1 (IDH1) mutations, which are early and frequent genetic alterations in gliomas, are specific to a single codon in the conserved and functionally important Arginine 132 (R132) in IDH1. We earlier established a monoclonal antibody (mAb), IMab-1, which is specific for R132H-containing IDH1 (IDH1-R132H), the most frequent IDH1 mutation in gliomas. To establish IDH1-R132S-specific mAb, we immunized mice with R132S-containing IDH1 (IDH1-R132S) peptide. After cell fusion using Sendai virus envelope, IDH1-R132S-specific mAbs were screened in ELISA. One mAb, SMab-1, reacted with the IDH1-R132S peptide, but not with other IDH1 mutants. Western-blot analysis showed that SMab-1 reacted only with the IDH1-R132S protein, not with IDH1-WT protein or IDH1 mutants, indicating that SMab-1 is IDH1-R132S-specific. Furthermore, SMab-1 specifically stained the IDH1-R132S-expressing glioblastoma cells in immunocytochemistry and immunohistochemistry, but did not react with IDH1-WT or IDH1-R132H-containing glioblastoma cells. We newly established an anti-IDH1-R132S-specific mAb SMab-1 for use in diagnosis of mutation-bearing gliomas.

Extensive gene conversion at the PMS2 DNA mismatch repair locus.

Science.gov (United States)

Hayward, Bruce E; De Vos, Michel; Valleley, Elizabeth M A; Charlton, Ruth S; Taylor, Graham R; Sheridan, Eamonn; Bonthron, David T

2007-05-01

Mutations of the PMS2 DNA repair gene predispose to a characteristic range of malignancies, with either childhood onset (when both alleles are mutated) or a partially penetrant adult onset (if heterozygous). These mutations have been difficult to detect, due to interference from a family of pseudogenes located on chromosome 7. One of these, the PMS2CL pseudogene, lies within a 100-kb inverted duplication (inv dup), 700 kb centromeric to PMS2 itself on 7p22. Here, we show that the reference genomic sequences cannot be relied upon to distinguish PMS2 from PMS2CL, because of sequence transfer between the two loci. The 7p22 inv dup occurred prior to the divergence of modern ape species (15 million years ago [Mya]), but has undergone extensive sequence homogenization. This process appears to be ongoing, since there is considerable allelic diversity within the duplicated region, much of it derived from sequence exchange between PMS2 and PMS2CL. This sequence diversity can result in both false-positive and false-negative mutation analysis at this locus. Great caution is still needed in the design and interpretation of PMS2 mutation screens. 2007 Wiley-Liss, Inc.

BRAF mutation-specific promoter methylation of FOX genes in colorectal cancer

NARCIS (Netherlands)

E.H.J. van Roon (Eddy); A. Boot (Arnoud); A.A. Dihal (Ashwin); R.F. Ernst (Robert); T. van Wezel (Tom); H. Morreau (Hans); J.M. Boer (Judith)

2013-01-01

textabstractBackground: Cancer-specific hypermethylation of (promoter) CpG islands is common during the tumorigenesis of colon cancer. Although associations between certain genetic aberrations, such as BRAF mutation and microsatellite instability, and the CpG island methylator phenotype (CIMP), have

CtIP Mutations Cause Seckel and Jawad Syndromes.

Directory of Open Access Journals (Sweden)

Per Qvist

2011-10-01

Full Text Available Seckel syndrome is a recessively inherited dwarfism disorder characterized by microcephaly and a unique head profile. Genetically, it constitutes a heterogeneous condition, with several loci mapped (SCKL1-5 but only three disease genes identified: the ATR, CENPJ, and CEP152 genes that control cellular responses to DNA damage. We previously mapped a Seckel syndrome locus to chromosome 18p11.31-q11.2 (SCKL2. Here, we report two mutations in the CtIP (RBBP8 gene within this locus that result in expression of C-terminally truncated forms of CtIP. We propose that these mutations are the molecular cause of the disease observed in the previously described SCKL2 family and in an additional unrelated family diagnosed with a similar form of congenital microcephaly termed Jawad syndrome. While an exonic frameshift mutation was found in the Jawad family, the SCKL2 family carries a splicing mutation that yields a dominant-negative form of CtIP. Further characterization of cell lines derived from the SCKL2 family revealed defective DNA damage induced formation of single-stranded DNA, a critical co-factor for ATR activation. Accordingly, SCKL2 cells present a lowered apoptopic threshold and hypersensitivity to DNA damage. Notably, over-expression of a comparable truncated CtIP variant in non-Seckel cells recapitulates SCKL2 cellular phenotypes in a dose-dependent manner. This work thus identifies CtIP as a disease gene for Seckel and Jawad syndromes and defines a new type of genetic disease mechanism in which a dominant negative mutation yields a recessively inherited disorder.

Nonsyndromic recessive deafness DFNB18 and Usher syndrome type IC are allelic mutations of USHIC.

Science.gov (United States)

Ahmed, Zubair M; Smith, Tenesha N; Riazuddin, Saima; Makishima, Tomoko; Ghosh, Manju; Bokhari, Sirosh; Menon, Puthezhath S N; Deshmukh, Dilip; Griffith, Andrew J; Riazuddin, Sheikh; Friedman, Thomas B; Wilcox, Edward R

2002-06-01

Human chromosome 11 harbors two Usher type I loci, USHIB and USHIC, which encode myosin VIIA and harmonin, respectively. The USHIC locus overlaps the reported critical interval for nonsyndromic deafness locus DFNB18. We found an IVS12+5G-->C mutation in the USHIC gene, which is associated with nonsyndromic recessive deafness ( DFNB18) segregating in the original family, S-11/12. No other disease-associated mutation was found in the other 27 exons or in the intron-exon boundaries, and the IVS12+5G-->C mutation was not present in 200 representative unaffected individuals ascertained from the same area of India. An exon-trapping assay with a construct harboring IVS12+5G-->C generated wildtype spliced mRNA having exons 11 and 12 and mRNA that skipped exon 12. We conclude that mutations of USHIC can cause both Usher syndrome type IC and nonsyndromic recessive deafness DFNB18.

Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

OpenAIRE

Bojesen, Stig E; Pooley, Karen A; Johnatty, Sharon E; Beesley, Jonathan; Michailidou, Kyriaki; Tyrer, Jonathan P; Edwards, Stacey L; Pickett, Hilda A; Shen, Howard C; Smart, Chanel E; Hillman, Kristine M; Mai, Phuong L; Lawrenson, Kate; Stutz, Michael D; Lu, Yi

2013-01-01

TERT-locus single nucleotide polymorphisms (SNPs) and leucocyte telomere measures are reportedly associated with risks of multiple cancers. Using the iCOGs chip, we analysed ~480 TERT-locus SNPs in breast (n=103,991), ovarian (n=39,774) and BRCA1 mutation carrier (11,705) cancer cases and controls. 53,724 participants have leucocyte telomere measures. Most associations cluster into three independent peaks. Peak 1 SNP rs2736108 minor allele associates with longer telomeres (P=5.8×10−7), reduce...

DHPLC-based mutation analysis of ENG and ALK-1 genes in HHT Italian population.

Science.gov (United States)

Lenato, Gennaro M; Lastella, Patrizia; Di Giacomo, Marilena C; Resta, Nicoletta; Suppressa, Patrizia; Pasculli, Giovanna; Sabbà, Carlo; Guanti, Ginevra

2006-02-01

Hereditary haemorrhagic telangiectasia (HHT or Rendu-Osler-Weber syndrome) is an autosomal dominant disorder characterized by localized angiodysplasia due to mutations in endoglin, ALK-1 gene, and a still unidentified locus. The lack of highly recurrent mutations, locus heterogeneity, and the presence of mutations in almost all coding exons of the two genes makes the screening for mutations time-consuming and costly. In the present study, we developed a DHPLC-based protocol for mutation detection in ALK1 and ENG genes through retrospective analysis of known sequence variants, 20 causative mutations and 11 polymorphisms, and a prospective analysis on 47 probands with unknown mutation. Overall DHPLC analysis identified the causative mutation in 61 out 66 DNA samples (92.4%). We found 31 different mutations in the ALK1 gene, of which 15 are novel, and 20, of which 12 are novel, in the ENG gene, thus providing for the first time the mutational spectrum in a cohort of Italian HHT patients. In addition, we characterized the splicing pattern of ALK1 gene in lymphoblastoid cells, both in normal controls and in two individuals carrying a mutation in the non-invariant -3 position of the acceptor splice site upstream exon 6 (c.626-3C>G). Functional essay demonstrated the existence, also in normal individuals, of a small proportion of ALK1 alternative splicing, due to exon 5 skipping, and the presence of further aberrant splicing isoforms in the individuals carrying the c.626-3C>G mutation. 2006 Wiley-Liss, Inc.

Detecting negative selection on recurrent mutations using gene genealogy

Science.gov (United States)

2013-01-01

Background Whether or not a mutant allele in a population is under selection is an important issue in population genetics, and various neutrality tests have been invented so far to detect selection. However, detection of negative selection has been notoriously difficult, partly because negatively selected alleles are usually rare in the population and have little impact on either population dynamics or the shape of the gene genealogy. Recently, through studies of genetic disorders and genome-wide analyses, many structural variations were shown to occur recurrently in the population. Such “recurrent mutations” might be revealed as deleterious by exploiting the signal of negative selection in the gene genealogy enhanced by their recurrence. Results Motivated by the above idea, we devised two new test statistics. One is the total number of mutants at a recurrently mutating locus among sampled sequences, which is tested conditionally on the number of forward mutations mapped on the sequence genealogy. The other is the size of the most common class of identical-by-descent mutants in the sample, again tested conditionally on the number of forward mutations mapped on the sequence genealogy. To examine the performance of these two tests, we simulated recurrently mutated loci each flanked by sites with neutral single nucleotide polymorphisms (SNPs), with no recombination. Using neutral recurrent mutations as null models, we attempted to detect deleterious recurrent mutations. Our analyses demonstrated high powers of our new tests under constant population size, as well as their moderate power to detect selection in expanding populations. We also devised a new maximum parsimony algorithm that, given the states of the sampled sequences at a recurrently mutating locus and an incompletely resolved genealogy, enumerates mutation histories with a minimum number of mutations while partially resolving genealogical relationships when necessary. Conclusions With their

Molecular analysis on germline mutation caused by low-dose irradiation

International Nuclear Information System (INIS)

Uchiyama, R.; Fujikawa, K.; Nishimura, M.; Adzuma, H.; Shimada, Y.; Yamauchi, M.

2003-01-01

Full text: Genetic heterogeneity and a low frequency of germline mutation at single-copy gene loci have limited the direct measurement of germline mutation in human populations. Two conflicting results have been reported for the effect of ionizing radiation on germline mutation in human populations. A study conducted on the first-generation progeny of the survivors of the atomic bombs at Hiroshima and Nagasaki found no significant increase in germline mutations. On the other hand, a significant increase in germline mutation was reported among the human population in the Belarus area after the Chernobyl accident in 1986. We investigated the germline mutation at the molecular level using experimental mouse strains with different genetic backgrounds to assess the risk of ionizing radiation on human populations. The C3H male parents were exposed to X ray (0, 0.3, 1, and 3Gy) and mated with unexposed C57BL females after two weeks interval, so as to detect the germline mutation occurred at the spermatid stage. Genomic DNA samples were prepared from the both parents and F1s, and the genomic DNA sequences were compared between parents and offspring at the specific genomic gene loci, such as adenine phosphoribosyl transferase (aprt) gene and cytidine triphosphate synthetase (ctps) gene, using the automated DNA sequencer. Also hypervariable Pc-1 (Ms6-hm) minisatellite repeat locus was analyzed by using Southern blot hybridization technique. Our preliminary results indicated that the changes of the restriction DNA fragment length in offspring did not reflect the occurrence of the mutation, such as point mutation, insertion, and deletion, in the genomic gene loci including the intervening sequence (intron)

Long-range PCR facilitates the identification of PMS2-specific mutations.

Science.gov (United States)

Clendenning, Mark; Hampel, Heather; LaJeunesse, Jennifer; Lindblom, Annika; Lockman, Jan; Nilbert, Mef; Senter, Leigha; Sotamaa, Kaisa; de la Chapelle, Albert

2006-05-01

Mutations within the DNA mismatch repair gene, "postmeiotic segregation increased 2" (PMS2), have been associated with a predisposition to hereditary nonpolyposis colorectal cancer (HNPCC; Lynch syndrome). The presence of a large family of highly homologous PMS2 pseudogenes has made previous attempts to sequence PMS2 very difficult. Here, we describe a novel method that utilizes long-range PCR as a way to preferentially amplify PMS2 and not the pseudogenes. A second, exon-specific, amplification from diluted long-range products enables us to obtain a clean sequence that shows no evidence of pseudogene contamination. This method has been used to screen a cohort of patients whose tumors were negative for the PMS2 protein by immunohistochemistry and had not shown any mutations within the MLH1 gene. Sequencing of the PMS2 gene from 30 colorectal and 11 endometrial cancer patients identified 10 novel sequence changes as well as 17 sequence changes that had previously been identified. In total, putative pathologic mutations were detected in 11 of the 41 families. Among these were five novel mutations, c.705+1G>T, c.736_741del6ins11, c.862_863del, c.1688G>T, and c.2007-1G>A. We conclude that PMS2 mutation detection in selected Lynch syndrome and Lynch syndrome-like patients is both feasible and desirable. Published 2006 Wiley-Liss, Inc.

Mutation induction in cultured human cells after low-dose and low-dose-rate γ-ray irradiation. Detection by LOH analysis

International Nuclear Information System (INIS)

Umebayashi, Yukihiro; Iwaki, Masaya; Yatagai, Fumio; Honma, Masamitsu; Suzuki, Masao; Suzuki, Hiromi; Shimazu, Toru; Ishioka, Noriaki

2007-01-01

To study the genetic effects of low-doses and low-dose-rate ionizing radiation (IR), human lymphoblastoid TK6 cells were exposed to 30 mGy of γ-rays at a dose-rate of 1.2 mGy/hr. The frequency of early mutations (EMs) in the thymidine kinase (TK) gene locus was determined to be 1.7 x 10 -6 , or 1.9-fold higher than the level seen in unirradiated controls. These mutations were analyzed with a loss of heterozygosity (LOH) detection system, a methodology which has been shown to be sensitive to the effects of radiation. Among the 15 EMs observed after IR exposure, 8 were small interstitial-deletion events restricted to the TK gene locus. However, this specific type of event was not found in unirradiated controls. Although these results were observed under the limited conditions, they strongly suggest that the LOH detection system can be used for estimating the genetic effects of a low-dose IR exposure delivered at a low-dose-rate. (author)

A magic bullet to specifically eliminate mutated mitochondrial genomes from patients' cells

Science.gov (United States)

Moraes, Carlos T

2014-01-01

When mitochondrial diseases result from mutations found in the mitochondrial DNA, engineered mitochondrial-targeted nucleases such as mitochondrial-targeted zinc finger nucleases are shown to specifically eliminate the mutated molecules, leaving the wild-type mitochondrial DNA intact to replicate and restore normal copy number. In this issue, Gammage and colleagues successfully apply this improved technology on patients' cells with two types of genetic alterations responsible for neuropathy ataxia and retinitis pigmentosa (NARP) syndrome and Kearns Sayre syndrome and progressive external ophthalmoplegia (PEO). PMID:24623377

Ras mutations are rare in solitary cold and toxic thyroid nodules.

Science.gov (United States)

Krohn, K; Reske, A; Ackermann, F; Müller, A; Paschke, R

2001-08-01

Activation of ras proto-oncogenes as a result of point mutations is detectable in a significant percentage of most types of tumour. Similar to neoplasms of other organs, mutations of all three ras genes can be found in thyroid tumours. H-, K- and N-ras mutations have been detected in up to 20% of follicular adenomas and adenomatous nodules which were not functionally characterized. This raises the question as to whether ras mutations are specific for hypofunctional nodules and TSH receptor mutations for hyperfunctioning nodules. To investigate ras and TSH receptor mutations with respect to functional differentiation we studied 41 scintigraphically cold nodules and 47 toxic thyroid nodules. To address the likelihood of a somatic mutation we also studied the clonal origin of these tumours. Genomic DNA was extracted from nodular and surrounding tissue. Mutational hot spots in exons 1 and 2 of the H- and K-ras gene were PCR amplified and sequenced using big dye terminator chemistry. Denaturing gradient gel electrophoresis (DGGE) was used to verify sequencing results for the H-ras gene and to analyse the N-ras gene because its greater sensitivity in detecting somatic mutations. Clonality of nodular thyroid tissue was evaluated using X-Chromosome inactivation based on PCR amplification of the human androgen receptor locus. Monoclonal origin was detectable in 14 of 23 informative samples from cold thyroid nodules. In toxic thyroid nodules the frequency of clonal tissue was 20 in 30 informative cases. Only one point mutation could be found in the N-ras gene codon 61 (Gly to Arg) in a cold adenomatous nodule which was monoclonal. In toxic thyroid nodules no ras mutation was detectable. Our study suggests that ras mutations are rare in solitary cold and toxic thyroid nodules and that the frequent monoclonal origin of these tumours implies somatic mutations in genes other than H-, K- and N-ras.

PETALS: Proteomic Evaluation and Topological Analysis of a mutated Locus' Signaling

Directory of Open Access Journals (Sweden)

Patel Vishal

2010-12-01

Full Text Available Abstract Background Colon cancer is driven by mutations in a number of genes, the most notorious of which is Apc. Though much of Apc's signaling has been mechanistically identified over the years, it is not always clear which functions or interactions are operative in a particular tumor. This is confounded by the presence of mutations in a number of other putative cancer driver (CAN genes, which often synergize with mutations in Apc. Computational methods are, thus, required to predict which pathways are likely to be operative when a particular mutation in Apc is observed. Results We developed a pipeline, PETALS, to predict and test likely signaling pathways connecting Apc to other CAN-genes, where the interaction network originating at Apc is defined as a "blossom," with each Apc-CAN-gene subnetwork referred to as a "petal." Known and predicted protein interactions are used to identify an Apc blossom with 24 petals. Then, using a novel measure of bimodality, the coexpression of each petal is evaluated against proteomic (2 D differential In Gel Electrophoresis, 2D-DIGE measurements from the Apc1638N+/-mouse to test the network-based hypotheses. Conclusions The predicted pathways linking Apc and Hapln1 exhibited the highest amount of bimodal coexpression with the proteomic targets, prioritizing the Apc-Hapln1 petal over other CAN-gene pairs and suggesting that this petal may be involved in regulating the observed proteome-level effects. These results not only demonstrate how functional 'omics data can be employed to test in silico predictions of CAN-gene pathways, but also reveal an approach to integrate models of upstream genetic interference with measured, downstream effects.

Decrease in specific micronutrient intake in colorectal cancer patients with tumors presenting Ki-ras mutation

OpenAIRE

JORDI SALAS; NURIA LASO; SERGI MAS; M. JOSE LAFUENTE; XAVIER CASTERAD; MANUEL TRIAS; ANTONIO BALLESTA; RAFAEL MOLINA; CARLOS ASCASO; SHICHUN ZHENG; JOHN K. WIENCKE; AMALIA LAFUENTE

2004-01-01

Decrease in specific micronutrient intake in colorectal cancer patients with tumors presenting Ki-ras mutation BACKGROUND: The diversity of the Mediterranean diet and the heterogeneity of acquired genetic alterations in colorectal cancer (CRC) led us to examine the possible association between dietary factors and mutations, such as Ki-ras mutations, in genes implicated in the pathogenesis of these neoplasms. PATIENTS AND METHODS: The study was based on 246 cases and 296 controls. For th...

The C allele of JAK2 rs4495487 is an additional candidate locus that contributes to myeloproliferative neoplasm predisposition in the Japanese population

Directory of Open Access Journals (Sweden)

Ohyashiki Junko H

2012-01-01

Full Text Available Abstract Background Polycythemia vera (PV, essential thrombocythemia (ET, and primary myelofibrosis (PMF are myeloproliferative neoplasms (MPNs characterized in most cases by a unique somatic mutation, JAK2 V617F. Recent studies revealed that JAK2 V617F occurs more frequently in a specific JAK2 haplotype, named JAK2 46/1 or GGCC haplotype, which is tagged by rs10974944 (C/G and/or rs12343867 (T/C. This study examined the impact of single nucleotide polymorphisms (SNPs of the JAK2 locus on MPNs in a Japanese population. Methods We sequenced 24 JAK2 SNPs in Japanese patients with PV. We then genotyped 138 MPN patients (33 PV, 96 ET, and 9 PMF with known JAK2 mutational status and 107 controls for a novel SNP, in addition to two SNPs known to be part of the 46/1 haplotype (rs10974944 and rs12343867. Associations with risk of MPN were estimated by odds ratios and their 95% confidence intervals using logistic regression. Results A novel locus, rs4495487 (T/C, with a mutated T allele was significantly associated with PV. Similar to rs10974944 and rs12343867, rs4495487 in the JAK2 locus is significantly associated with JAK2-positive MPN. Based on the results of SNP analysis of the three JAK2 locus, we defined the "GCC genotype" as having at least one minor allele in each SNP (G allele in rs10974944, C allele in rs4495487, and C allele in rs12343867. The GCC genotype was associated with increased risk of both JAK2 V617F-positive and JAK2 V617F-negative MPN. In ET patients, leukocyte count and hemoglobin were significantly associated with JAK2 V617F, rather than the GCC genotype. In contrast, none of the JAK2 V617F-negative ET patients without the GCC genotype had thrombosis, and splenomegaly was frequently seen in this subset of ET patients. PV patients without the GCC genotype were significantly associated with high platelet count. Conclusions Our results indicate that the C allele of JAK2 rs4495487, in addition to the 46/1 haplotype, contributes

Insights into the binding specificity of wild type and mutated wheat germ agglutinin towards Neu5Acα(2-3)Gal: a study by in silico mutations and molecular dynamics simulations.

Science.gov (United States)

Parasuraman, Ponnusamy; Murugan, Veeramani; Selvin, Jeyasigamani F A; Gromiha, M Michael; Fukui, Kazuhiko; Veluraja, Kasinadar

2014-08-01

Wheat germ agglutinin (WGA) is a plant lectin, which specifically recognizes the sugars NeuNAc and GlcNAc. Mutated WGA with enhanced binding specificity can be used as biomarkers for cancer. In silico mutations are performed at the active site of WGA to enhance the binding specificity towards sialylglycans, and molecular dynamics simulations of 20 ns are carried out for wild type and mutated WGAs (WGA1, WGA2, and WGA3) in complex with sialylgalactose to examine the change in binding specificity. MD simulations reveal the change in binding specificity of wild type and mutated WGAs towards sialylgalactose and bound conformational flexibility of sialylgalactose. The mutated polar amino acid residues Asn114 (S114N), Lys118 (G118K), and Arg118 (G118R) make direct and water mediated hydrogen bonds and hydrophobic interactions with sialylgalactose. An analysis of possible hydrogen bonds, hydrophobic interactions, total pair wise interaction energy between active site residues and sialylgalactose and MM-PBSA free energy calculation reveals the plausible binding modes and the role of water in stabilizing different binding modes. An interesting observation is that the binding specificity of mutated WGAs (cyborg lectin) towards sialylgalactose is found to be higher in double point mutation (WGA3). One of the substituted residues Arg118 plays a crucial role in sugar binding. Based on the interactions and energy calculations, it is concluded that the order of binding specificity of WGAs towards sialylgalactose is WGA3 > WGA1 > WGA2 > WGA. On comparing with the wild type, double point mutated WGA (WGA3) exhibits increased specificity towards sialylgalactose, and thus, it can be effectively used in targeted drug delivery and as biological cell marker in cancer therapeutics. Copyright © 2014 John Wiley & Sons, Ltd.

Evaluation of Lama5 as a candidate for the mouse ragged (Ra) mutation

DEFF Research Database (Denmark)

Durkin, M E; Albrechtsen, R; Chambers, D M

1998-01-01

The laminin alpha5 chain is a component of the basement membranes of many developing and adult tissues. The mouse laminin alpha5 chain gene (Lama5) has been mapped close to the locus of the semidominant ragged (Ra) mutation on distal chromosome 2. The cause of the Ra mutation, which is usually...... lethal in the homozygous state, has not been determined. We have investigated whether a defect in Lama5 is responsible for the ragged mutation, using the RaJ strain. No differences in the level of the laminin alpha5 chain transcript were found in placental RNA from homozygous RaJ mutant embryos compared...... to normal littermates. Antiserum raised against a recombinant laminin alpha5 chain polypeptide stained the basement membranes of both normal and homozygous mutant embryos to a similar extent. More precise mapping of Lama5 on an interspecific Ra backcross indicated that Lama5 is proximal to the Ra locus...

Genomic mutation study for long-term cells induced by carbon ions

International Nuclear Information System (INIS)

Wang, X.; Furusawa, Y.; Suzuki, M.; Hirayama, R.; Matsumoto, Y.; Qin, Y.

2007-01-01

Complete text of publication follows. Objective: Densely ionizing (high LET) radiation can increase the relative biological effectiveness of cell and tissue. Astronauts in the space exploration have the potential exposure of chronic low-dose radiations in the field of low-flux galactic cosmic rays (GCR) and the subsequent biological effects have become one of the major concerns of space science. Furthermore, Heavy ions also are used new radiation therapy owing increased lethal effectiveness of high LET radiation. During radiation therapy, normal tissues also are exposed to ionizing radiation. Radiation can induce genomic mutation and instability in descendants of irradiated cells. Induction of genomic instability can represent one of the initiating steps leading to malignant transformation. Higher frequencies of mutation can be expected to provide higher rates of carcinogenicity with human exposure. Therefore, the study of radiation induced genomic mutation and instability is relevant to the estimates of the risk of secondary malignancies associated with radiation therapy and the carcinogenic effects of space environmental radiation. The hypoxanthine-guanine phosphoribosyltransferase (hprt) locus has been the most commonly used as a target gene for mutation detection studies. In this study, we investigated the generation expression dependence of mutation induction on HPRT locus in CHO cells irradiated with carbon ions. Methods: Chinese hamster ovary (CHO) cells were irradiated with graded doses of carbon ions (290MeV/u, LET:13kev/um) accelerated with Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences(NIRS). The survival effect of cells plated immediately after irradiation was measured with cell colony formation assay. After irradiation, cells were continues reseeding and cultures for lone-term proliferation. Cell samples were collected at 6, 12, 18, 24, 30, 37 and 44 days post irradiation. Mutation induction of cell

Neonatal pulmonary arterial hypertension and Noonan syndrome: two fatal cases with a specific RAF1 mutation.

Science.gov (United States)

Hopper, Rachel K; Feinstein, Jeffrey A; Manning, Melanie A; Benitz, William; Hudgins, Louanne

2015-04-01

Mutations in RAF1 are associated with Noonan syndrome and hypertrophic cardiomyopathy. We present two infants with Noonan syndrome and an identical RAF1 mutation, p.Ser257Leu (c.770C>T), who developed severe pulmonary arterial hypertension (PAH) that proved to be fatal. The RAF1 gene encodes Raf-1 kinase, part of the Ras/mitogen-activated kinase (MAPK) signaling pathway, which has been linked to the development of PAH. This specific mutation has been associated with dephosphorylation of a critical serine residue and constitutive activation of the Raf-1 kinase. These two cases suggest that abnormal activation of the Ras/MAPK pathway may play a significant role in the development of pulmonary vascular disease in the subset of patients with Noonan syndrome and a specific RAF1 mutation. © 2015 Wiley Periodicals, Inc.

Analysis of mammary specific gene locus regulation in differentiated cells derived by somatic cell fusion

International Nuclear Information System (INIS)

Robinson, Claire; Kolb, Andreas F.

2009-01-01

The transcriptional regulation of a gene is best analysed in the context of its normal chromatin surroundings. However, most somatic cells, in contrast to embryonic stem cells, are refractory to accurate modification by homologous recombination. We show here that it is possible to introduce precise genomic modifications in ES cells and to analyse the phenotypic consequences in differentiated cells by using a combination of gene targeting, site-specific recombination and somatic cell fusion. To provide a proof of principle, we have analysed the regulation of the casein gene locus in mammary gland cells derived from modified murine ES cells by somatic cell fusion. A β-galactosidase reporter gene was inserted in place of the β-casein gene and the modified ES cells, which do not express the reporter gene, were fused with the mouse mammary gland cell line HC11. The resulting cell clones expressed the β-galactosidase gene to a similar extent and with similar hormone responsiveness as the endogenous gene. However, a reporter gene under the control of a minimal β-casein promoter (encompassing the two consensus STAT5 binding sites which mediate the hormone response of the casein genes) was unable to replicate expression levels or hormone responsiveness of the endogenous gene when inserted into the same site of the casein locus. As expected, these results implicate sequences other than the STAT5 sites in the regulation of the β-casein gene

Exome mutation burden predicts clinical outcome in ovarian cancer carrying mutated BRCA1 and BRCA2 genes

DEFF Research Database (Denmark)

Birkbak, Nicolai Juul; Kochupurakkal, Bose; Gonzalez-Izarzugaza, Jose Maria

2013-01-01

drugs and relative to non-mutation carriers present a favorable clinical outcome following therapy. Genome sequencing studies have shown a high number of mutations in the tumor genome in patients carrying BRCA1 or BRCA2 mutations (mBRCA). The present study used exome-sequencing and SNP 6 array data...... between low Nmut and shorter PFS and OS in mBRCA HGSOC by Cox regression and Kaplan-Meier analyses. The association was also significant when the analysis was limited to germline BRCA1 or BRCA2 mutated patients with SNP array-determined loss of heterozygosity of the BRCA1 or BRCA2 locus in the tumors....... In the mBRCA HGSOC tumors, Nmut was correlated with the genome fraction with loss of heterozygosity and with number of telomeric allelic imbalance, genomic measures evaluating chromosomal instability. However, no significant association between Nmut and PFS or OS was found in HGSOC carrying wild-type BRCA1...

Protection against radiation-induced mutations at the hprt locus by spermine and N,N double-prime-(dithiodi-2,1-ethanediyl)bis-1,3-propanediamine (WR-33278). WR-33278 and spermine protect against mutation induction

International Nuclear Information System (INIS)

Grdina, D.J.; Shigematsu, N.; Schwartz, J.L.

1994-01-01

The polyamine spermine and the disulfide N,N double-prime-(dithiodi-2,1-ethanediyl)bis-1,3-propanediamine (WR-33278) are structurally similar agents capable of binding to DNA. WR-33278 is the disulfide moiety of the clinically studied radioprotective agent S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721). Because of their reported structural and functional similarities, it was of interest to characterize and compare their radioprotective properties using the endpoints of cell survival and mutation induction at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus in Chinese hamster AA8 cells. In order to facilitate both the uptake of WR-33278 into cells and the direct comparison between the protective properties of WR-33278 and spermine, these agents (at concentrations of 0.01 mM and 0.001 mM) were electroporated into cells. The exposure of cells to both electroporation and irradiation gave rise to enhanced cell killing and mutation induction, with the sequence of irradiation followed 3 h later by electroporation being the more toxic protocol. Enhanced cell survival was observed following electroporation of 0.01 mM of spermine and WR-33278 30 min prior to irradiation; protection factors (PF) of 1.3 and 1.8, respectively. Neither agent was protective at a concentration of 0.001 mM. Protection against radiation-induced hprt mutations was observed for both spermine and WR-33278 under all experimental conditions tested. These data suggest that the properties of radioprotection and chemoprevention exhibited by the phosphorothioate (WR-2721) and associated aminothiol (WR-1065) and disulfide (WR-33278) metabolites may be mediated via endogenous spermine-like polyamine processes. Such a mechanism would have important implications with respect to the design and development of new generation drugs for use in radioprotection and chemoprevention

Specific and Efficient Regression of Cancers Harboring KRAS Mutation by Targeted RNA Replacement.

Science.gov (United States)

Kim, Sung Jin; Kim, Ju Hyun; Yang, Bitna; Jeong, Jin-Sook; Lee, Seong-Wook

2017-02-01

Mutations in the KRAS gene, which persistently activate RAS function, are most frequently found in many types of human cancers. Here, we proposed and verified a new approach against cancers harboring the KRAS mutation with high cancer selectivity and efficient anti-cancer effects based on targeted RNA replacement. To this end, trans-splicing ribozymes from Tetrahymena group I intron were developed, which can specifically target and reprogram the mutant KRAS G12V transcript to induce therapeutic gene activity in cells. Adenoviral vectors containing the specific ribozymes with downstream suicide gene were constructed and then infection with the adenoviruses specifically downregulated KRAS G12V expression and killed KRAS G12V-harboring cancer cells additively upon pro-drug treatment, but it did not affect the growth of wild-type KRAS-expressing cells. Minimal liver toxicity was noted when the adenoviruses were administered systemically in vivo. Importantly, intratumoral injection of the adenoviruses with pro-drug treatment specifically and significantly impeded the growth of xenografted tumors harboring KRAS G12V through a trans-splicing reaction with the target RNA. In contrast, xenografted tumors harboring wild-type KRAS were not affected by the adenoviruses. Therefore, RNA replacement with a mutant KRAS-targeting trans-splicing ribozyme is a potentially useful therapeutic strategy to combat tumors harboring KRAS mutation. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

Does cognitive training improve internal locus of control among older adults?

Science.gov (United States)

Wolinsky, Fredric D; Vander Weg, Mark W; Martin, René; Unverzagt, Frederick W; Willis, Sherry L; Marsiske, Michael; Rebok, George W; Morris, John N; Ball, Karlene K; Tennstedt, Sharon L

2010-09-01

We evaluated the effect of cognitive training among 1,534 participants in the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) randomized controlled trial (RCT) on 5-year improvements in 3 cognitive-specific measures of locus of control-internal, chance, and powerful others. ACTIVE was a multisite RCT (age > or = 65), with 4 groups (memory, reasoning, speed of processing, and no-contact control). Complete 5-year follow-up data were available for 1,534 (55%) of the 2,802 participants. A propensity score model was used to adjust for potential attrition bias. Clinically important improvements (and decrements) in the cognitive-specific locus of control scale scores were defined as greater than or equal to 0.5 SD (medium) and greater than or equal to 1.0 SD (large). Multinomial logistic regression was used to simultaneously contrast those who improved and those who declined with those whose locus of control scale score was unchanged. Statistically significant effects reflecting medium-sized (> or = 0.5 SD) improvements in internal locus of control between baseline and the 5-year follow-up were found for the reasoning and speed of processing intervention groups who were 76% (p control group. No improvement effects were found on the chance or powerful others locus of control measures or for the memory intervention group. Cognitive training that targets reasoning and speed of processing can improve the cognitive-specific sense of personal control over one's life in older adults.

Microsatellite and single nucleotide polymorphisms in the β-globin locus control region-hypersensitive Site 2: SPECIFICITY of Tunisian βs chromosomes.

Science.gov (United States)

Ben Mustapha, Maha; Moumni, Imen; Zorai, Amine; Douzi, Kaïs; Ghanem, Abderraouf; Abbes, Salem

2012-01-01

The diversity of sickle cell disease severity is attributed to several cis acting factors, among them the single nucleotide polymorphisms (SNPs) and (AT) rich region in the β-locus control region (β-LCR). This contains five DNase I hypersensitive sites (HS) located 6 to 22 kb upstream to the ϵ gene. The most important of these is the HS2 (5' β-LCR-HS2), characterized by the presence of three different SNPs and a microsatellite region known to be in association with β(S) chromosomes in various populations. The aim of this study was to present the molecular investigation of the 5' β-LCR-HS2 site in normal and sickle cell disease individuals in order to determine if there is any correlation or specificity between these molecular markers, the β(S) Tunisian chromosomes and phenotypical expression of sickle cell disease. One hundred and twenty-four chromosomes from Tunisian individuals (49 β(S) carriers and 13 normal individuals) were screened by polymerase chain reaction (PCR) and sequencing for the polymorphic short tandem microsatellite repeats (AT)(X)N(12)(AT)(Y) and the three SNPs (rs7119428, rs9736333 and rs60240093) of the 5' β-LCR-HS2. Twelve configurations of the microsatellite motif were found with an ancestral configuration elaborated by ClustalW software. Normal and mutated alleles were observed at the homozygous and heterozygous states for the three SNPs. Correlation between microsatellites and SNPs suggests that mutant SNP alleles were mainly associated, in the homozygous sickle cell disease phenotype, with the (AT)(8)N(12)GT(AT)(7) configuration, whereas, normal SNP alleles were associated with the (AT)(X)N(12)(AT)(11) configurations in normal β(A) chromosomes. The correlation of these various configurations with Hb F expression was also investigated. The principal component analysis (PCA) showed the correlation between the homozygous sickle cell disease phenotype, mutated SNP alleles and the Benin microsatellite configuration (AT)(8)N(12)GT

SLC26A4 mutations are associated with a specific inner ear malformation.

Science.gov (United States)

Fitoz, Suat; Sennaroğlu, Levent; Incesulu, Armağan; Cengiz, Filiz Başak; Koç, Yasemin; Tekin, Mustafa

2007-03-01

Inner ear anomalies have been reported in approximately 30% of children with early onset deafness. Identification of causative genetic factors in a large proportion of these patients was not successful. Mutations in the SLC26A4 gene have been detected in individuals with enlarged vestibular aqueduct (EVA) or Mondini dysplasia. We aimed to characterize the inner ear anomalies associated with SLC26A4 mutations. The SLC26A4 gene has been screened for mutations in 16 subjects from 14 unrelated Turkish families with a variety of inner ear anomalies ranging from Michel aplasia to incomplete partition-II and EVA. None of the patients was diagnosed to have a recognizable genetic syndrome. Additional four patients with Pendred syndrome from three families were included. Only one patient with EVA was found to have a heterozygous mutation (c.1586delT) in SLC26A4. All patients with Pendred syndrome had homozygous mutations and were noted to have either EVA or EVA associated with incomplete partition-II on the computed tomography of the temporal bone. SLC26A4 mutations are not associated with a large spectrum of inner ear anomalies. They, instead, result in a specific morphological appearance consistent with EVA or incomplete partition-II.

Sequential mutations in Notch1, Fbxw7, and Tp53 in radiation-induced mouse thymic lymphomas.

Science.gov (United States)

Jen, Kuang-Yu; Song, Ihn Young; Banta, Karl Luke; Wu, Di; Mao, Jian-Hua; Balmain, Allan

2012-01-19

T-cell acute lymphoblastic lymphomas commonly demonstrate activating Notch1 mutations as well as mutations or deletions in Fbxw7. However, because Fbxw7 targets Notch1 for degradation, genetic alterations in these genes are expected to be mutually exclusive events in lymphomagenesis. Previously, by using a radiation-induced Tp53-deficient mouse model for T-cell acute lymphoblastic lymphoma, we reported that loss of heterozygosity at the Fbxw7 locus occurs frequently in a Tp53-dependent manner. In the current study, we show that these thymic lymphomas also commonly exhibit activating Notch1 mutations in the proline-glutamic acid-serine-threonine (PEST) domain. Moreover, concurrent activating Notch1 PEST domain mutations and single-copy deletions at the Fbxw7 locus occur with high frequency in the same individual tumors, indicating that these changes are not mutually exclusive events. We further demonstrate that although Notch1 PEST domain mutations are independent of Tp53 status, they are completely abolished in mice with germline Fbxw7 haploinsufficiency. Therefore, Notch1 PEST domain mutations only occur when Fbxw7 expression levels are intact. These data suggest a temporal sequence of mutational events involving these important cancer-related genes, with Notch1 PEST domain mutations occurring first, followed by Fbxw7 deletion, and eventually by complete loss of Tp53.

Two truncating USH3A mutations, including one novel, in a German family with Usher syndrome.

Science.gov (United States)

Ebermann, Inga; Wilke, Robert; Lauhoff, Thomas; Lübben, Dirk; Zrenner, Eberhart; Bolz, Hanno Jörn

2007-08-30

To identify the genetic defect in a German family with Usher syndrome (USH) and linkage to the USH3A locus. DNA samples of five family members (both parents and the three patients) were genotyped with polymorphic microsatellite markers specific for eight USH genes. Three affected family members underwent detailed ocular and audiologic characterization. Symptoms in the patients were compatible with Usher syndrome and show intrafamilial variation, for both hearing loss (ranging from severe to profound with non-linear progression) and vision. Genotyping of microsatellite markers for the different USH loci was in line with a defect in the USH3A gene on chromosome 3q25. Sequence analysis of the USH3A gene revealed two truncating mutations; c.149_152delCAGGinsTGTCCAAT, which has been described previously, and a novel mutation, c.502_503insA, segregating with the phenotype. To date, only 11 USH3A mutations have been described. This is the first description of a German family with USH due to USH3A mutations, including one novel. Our findings indicate that also in the Central European population, USH3A mutations should be considered in cases of USH.

Clinical variability of Waardenburg-Shah syndrome in patients with proximal 13q deletion syndrome including the endothelin-B receptor locus.

Science.gov (United States)

Tüysüz, Beyhan; Collin, Anna; Arapoğlu, Müjde; Suyugül, Nezir

2009-10-01

Waardenburg-Shah syndrome (Waardenburg syndrome type IV-WS4) is an auditory-pigmentary disorder that combines clinical features of pigmentary abnormalities of the skin, hair and irides, sensorineural hearing loss, and Hirschsprung disease (HSCR). Mutations in the endothelin-B receptor (EDNRB) gene on 13q22 have been found to cause this syndrome. Mutations in both alleles cause the full phenotype, while heterozygous mutations cause isolated HSCR or HSCR with minor pigmentary anomalies and/or sensorineural deafness. We investigated the status of the EDNRB gene, by FISH analysis, in three patients with de novo proximal 13q deletions detected at cytogenetic analysis and examined the clinical variability of WS4 among these patients. Chromosome 13q was screened with locus specific FISH probes and breakpoints were determined at 13q22.1q31.3 in Patients 1 and 3, and at 13q21.1q31.3 in Patient 2. An EDNRB specific FISH probe was deleted in all three patients. All patients had common facial features seen in proximal 13q deletion syndrome and mild mental retardation. However, findings related to WS4 were variable; Patient 1 had hypopigmentation of the irides and HSCR, Patient 2 had prominent bicolored irides and mild bilateral hearing loss, and Patient 3 had only mild unilateral hearing loss. These data contribute new insights into the pathogenesis of WS4.

Molecular and Recombinational Mapping of Mutations in the Ace Locus of Drosophila melanogaster

OpenAIRE

Nagoshi, Rodney N.; Gelbart, William M.

1987-01-01

The Ace locus in Drosophila melanogaster is known to be the structural gene for acetylcholinesterase. Ace is located in a region of chromosome arm 3R which has been subjected to intensive genetic and molecular analysis. Previous deletion mapping studies have identified a 40-kb region within which the Ace gene resides. This report focuses on the further localization of Ace within this 40-kb interval. Within this region, selective fine structure recombinational analysis was employed to localize...

GBA mutations in Gaucher type I Venezuelan patients: ethnic origins ...

Indian Academy of Sciences (India)

Gaucher disease (GD), the most frequent lysosomal storage disease, is caused by heterogeneous mutations in the locus coding for glucocerebrosidase (GBA). It is an autosomal recessive disorder with different phenotypes of which the most frequent is the nonneuronopathic or type 1, prevalent worldwide. To date, more ...

2-O-α-glucopytanosyl L-ascorbic acid reduced mutagenicity at HPRT locus of mouse splenocytes following BNCT

International Nuclear Information System (INIS)

Kinashi, Yuko; Masunaga, Shin-ichiro; Suzuki, Minoru; Nagata, Kanji; Ono, Koji

2006-01-01

In boron neutron capture therapy (BNCT), normal tissue surrounding the tumor cells sometimes take up boron compounds resulting in radiation-induced damage to normal tissue. We have previously reported the evidence for increased the mutagenicity of thermal neutron in the presence of boron. In addition, we described the biological radio-protective effects of the ascorbic acid for mutation induction following BNCT in vitro. Here, we investigated these radio-protective effects of ascorbic acid for mutation induction in mouse splenocytes on HPRT locus following a BNCT study in vivo. (author)

Allelic variations at the haploid TBX1 locus do not influence the cardiac phenotype in cases of 22q11 microdeletion.

Science.gov (United States)

Voelckel, Marie-Antoinette; Girardot, Lydie; Giusiano, Bernard; Levy, Nicolas; Philip, Nicole

2004-01-01

Microdeletion at the 22q11 locus is characterised by a high clinical variability. Congenital heart defects (CHD) are the most life-threatening manifestations of the syndrome and affect approximately 50% of patients carrying the deleted chromosome 22. The causes of this phenotype variability remain unknown although several hypotheses have been raised. It has been suggested that allelic variations at the haploid locus could modify the phenotypic expression. Regarding this hypothesis, TBX1 was thought to be a major candidate to the cardiac phenotype or its severity in patients carrying the 22q11 microdeletion. A mutational screening was performed in this gene, in a series of 39 deleted patients, with and without CHD. The results indicate that mutations in TBX1 are not likely to be involved in the cardiac phenotype observed in del22q11 patients.

[Analysis of allele dropout at TH01 locus in paternity testing].

Science.gov (United States)

Lai, Li; Shen, Xiao-li; Xue, Shi-jie; Hu, Jie

2013-10-01

To analyze allele dropout at TH01 locus in paternity testing in order to determine the accurate genotype. To use a two STR loci genotyping system to verify an abnormal genotype for the TH01 locus with PCR using specific primers, cloning and DNA sequencing. A rare allele at TH01 locus named 5.2, which was undetectable with PowerPlex 21 system, was detected with an Identifiler system. Genetic variations may result in rare alleles and loci loss. To avoid misjudgment, laboratories should have a variety of methods for detecting loci loss.

Mucopolysaccharidosis IVA: Four new exonic mutations in patients with N-acetylgalactosamine-6-sulfate sulfatase deficiency

Energy Technology Data Exchange (ETDEWEB)

Tomatsu, Shunji; Fukuda, Seiji; Yamagishi, Atsushi [Gifu Univ. (Japan)] [and others

1996-05-01

We report four new mutations in Japanese patients with mucopolysaccharidosis IVA (MPSIVA) who were heterozygous for a common double gene deletion. A nonsense mutation of CAG to TAG at codon 148 in exon 4 was identified, resulting in a change of Q to a stop codon and three missense mutations: V (GTC) to A (GCC) at codon 138 in exon 4, P (CCC) to S (TCC) at codon 151 in exon 5, and P (CCC) to L (CTC) at codon 151 in exon 5. Introduction of these mutations into the normal GALNS cDNA and transient expression in cultured fibroblasts resulted in a significant decrease in the enzyme activity. V138A and Q148X mutations result in changes of restriction site, which were analyzed by restriction-enzyme assay. P151S and P151L mutations that did not alter the restriction site were detected by direct sequencing or allele specific oligohybridization. Detection of the double gene deletion was initially done using Southern blots and was confirmed by PCR. Haplotypes were determined using seven polymorphisms to the GALNS locus in families with the double gene deletion. Haplotype analysis showed that the common double gene deletion occurred on a single haplotype, except for some variation in a VNTR-like polymorphism. This finding is consistent with a common founder for all individuals with this mutation. 48 refs., 5 figs., 1 tab.

Introgression of the callipyge mutation into the Assaf fat tail breed

International Nuclear Information System (INIS)

Gootwine, E.; Rosov, A.; Bor, A.; Yossafi, S.; Zenue, A.

2003-01-01

Introgression of the callipyge (CLPG) mutation into the fat-tail Assaf breed was initiated by inseminating Assaf ewes with Dorset-Hampshire semen from a ram that was heterozygous for the callipyge mutation. Presence of the mutation in the F1 generation and the first backcross generation (BC1) was validated using molecular markers linked to the CLPG locus. Carcasses of callipyge BC1-CN lambs had significantly (P less than 0.01) better conformation than carcasses of normal BC1-NN lambs and straightbred Assaf lambs. Computerized tomography analysis of live BC1 and Assaf lambs showed that carrying the callipyge mutation increased Longissimus dorsi and Quadriceps femoris muscles by about 30

Molecular methods for the detection of mutations.

Science.gov (United States)

Monteiro, C; Marcelino, L A; Conde, A R; Saraiva, C; Giphart-Gassler, M; De Nooij-van Dalen, A G; Van Buuren-van Seggelen, V; Van der Keur, M; May, C A; Cole, J; Lehmann, A R; Steinsgrimsdottir, H; Beare, D; Capulas, E; Armour, J A

2000-01-01

We report the results of a collaborative study aimed at developing reliable, direct assays for mutation in human cells. The project used common lymphoblastoid cell lines, both with and without mutagen treatment, as a shared resource to validate the development of new molecular methods for the detection of low-level mutations in the presence of a large excess of normal alleles. As the "gold standard, " hprt mutation frequencies were also measured on the same samples. The methods under development included i) the restriction site mutation (RSM) assay, in which mutations lead to the destruction of a restriction site; ii) minisatellite length-change mutation, in which mutations lead to alleles containing new numbers of tandem repeat units; iii) loss of heterozygosity for HLA epitopes, in which antibodies can be used to direct selection for mutant cells; iv) multiple fluorescence-based long linker arm nucleotides assay (mf-LLA) technology, for the detection of substitutional mutations; v) detection of alterations in the TP53 locus using a (CA) array as the target for the screening; and vi) PCR analysis of lymphocytes for the presence of the BCL2 t(14:18) translocation. The relative merits of these molecular methods are discussed, and a comparison made with more "traditional" methods.

The human PINK1 locus is regulated in vivo by a non-coding natural antisense RNA during modulation of mitochondrial function

Directory of Open Access Journals (Sweden)

Wahlestedt Claes

2007-03-01

Full Text Available Abstract Background Mutations in the PTEN induced putative kinase 1 (PINK1 are implicated in early-onset Parkinson's disease. PINK1 is expressed abundantly in mitochondria rich tissues, such as skeletal muscle, where it plays a critical role determining mitochondrial structural integrity in Drosophila. Results Herein we characterize a novel splice variant of PINK1 (svPINK1 that is homologous to the C-terminus regulatory domain of the protein kinase. Naturally occurring non-coding antisense provides sophisticated mechanisms for diversifying genomes and we describe a human specific non-coding antisense expressed at the PINK1 locus (naPINK1. We further demonstrate that PINK1 varies in vivo when human skeletal muscle mitochondrial content is enhanced, supporting the idea that PINK1 has a physiological role in mitochondrion. The observation of concordant regulation of svPINK1 and naPINK1 during in vivo mitochondrial biogenesis was confirmed using RNAi, where selective targeting of naPINK1 results in loss of the PINK1 splice variant in neuronal cell lines. Conclusion Our data presents the first direct observation that a mammalian non-coding antisense molecule can positively influence the abundance of a cis-transcribed mRNA under physiological abundance conditions. While our analysis implies a possible human specific and dsRNA-mediated mechanism for stabilizing the expression of svPINK1, it also points to a broader genomic strategy for regulating a human disease locus and increases the complexity through which alterations in the regulation of the PINK1 locus could occur.

Specific regulation of point-mutated K-ras-immortalized cell proliferation by a photodynamic antisense strategy.

Science.gov (United States)

Higuchi, Maiko; Yamayoshi, Asako; Kato, Kiyoko; Kobori, Akio; Wake, Norio; Murakami, Akira

2010-02-01

It has been reported that point mutations in genes are responsible for various cancers, and the selective regulation of gene expression is an important factor in developing new types of anticancer drugs. To develop effective drugs for the regulation of point-mutated genes, we focused on photoreactive antisense oligonucleotides. Previously, we reported that photoreactive oligonucleotides containing 2'-O-psoralenylmethoxyethyl adenosine (2'-Ps-eom) showed drastic photoreactivity in a strictly sequence-specific manner. Here, we demonstrated the specific gene regulatory effects of 2'-Ps-eom on [(12)Val]K-ras mutant (GGT --> GTT). Photo-cross-linking between target mRNAs and 2'-Ps-eom was sequence-specific, and the effect was UVA irradiation-dependent. Furthermore, 2'-Ps-eom was able to inhibit K-ras-immortalized cell proliferation (K12V) but not Vco cells that have the wild-type K-ras gene. These results suggest that the 2'-Ps-eom will be a powerful nucleic acid drug to inhibit the expression of disease-causing point mutation genes, and has great therapeutic potential in the treatment of cancer.

Mutation update for the CSB/ERCC6 and CSA/ERCC8 genes involved in Cockayne syndrome.

Science.gov (United States)

Laugel, V; Dalloz, C; Durand, M; Sauvanaud, F; Kristensen, U; Vincent, M C; Pasquier, L; Odent, S; Cormier-Daire, V; Gener, B; Tobias, E S; Tolmie, J L; Martin-Coignard, D; Drouin-Garraud, V; Heron, D; Journel, H; Raffo, E; Vigneron, J; Lyonnet, S; Murday, V; Gubser-Mercati, D; Funalot, B; Brueton, L; Sanchez Del Pozo, J; Muñoz, E; Gennery, A R; Salih, M; Noruzinia, M; Prescott, K; Ramos, L; Stark, Z; Fieggen, K; Chabrol, B; Sarda, P; Edery, P; Bloch-Zupan, A; Fawcett, H; Pham, D; Egly, J M; Lehmann, A R; Sarasin, A; Dollfus, H

2010-02-01

Cockayne syndrome is an autosomal recessive multisystem disorder characterized principally by neurological and sensory impairment, cachectic dwarfism, and photosensitivity. This rare disease is linked to mutations in the CSB/ERCC6 and CSA/ERCC8 genes encoding proteins involved in the transcription-coupled DNA repair pathway. The clinical spectrum of Cockayne syndrome encompasses a wide range of severity from severe prenatal forms to mild and late-onset presentations. We have reviewed the 45 published mutations in CSA and CSB to date and we report 43 new mutations in these genes together with the corresponding clinical data. Among the 84 reported kindreds, 52 (62%) have mutations in the CSB gene. Many types of mutations are scattered along the whole coding sequence of both genes, but clusters of missense mutations can be recognized and highlight the role of particular motifs in the proteins. Genotype-phenotype correlation hypotheses are considered with regard to these new molecular and clinical data. Additional cases of molecular prenatal diagnosis are reported and the strategy for prenatal testing is discussed. Two web-based locus-specific databases have been created to list all identified variants and to allow the inclusion of future reports (www.umd.be/CSA/ and www.umd.be/CSB/). (c) 2009 Wiley-Liss, Inc.

USH1H, a novel locus for type I Usher syndrome, maps to chromosome 15q22-23.

Science.gov (United States)

Ahmed, Z M; Riazuddin, S; Khan, S N; Friedman, P L; Riazuddin, S; Friedman, T B

2009-01-01

Usher syndrome (USH) is a hereditary disorder associated with sensorineural hearing impairment, progressive loss of vision attributable to retinitis pigmentosa (RP) and variable vestibular function. Three clinical types have been described with type I (USH1) being the most severe. To date, six USH1 loci have been reported. We ascertained two large Pakistani consanguineous families segregating profound hearing loss, vestibular dysfunction, and RP, the defining features of USH1. In these families, we excluded linkage of USH to the 11 known USH loci and subsequently performed a genome-wide linkage screen. We found a novel USH1 locus designated USH1H that mapped to chromosome 15q22-23 in a 4.92-cM interval. This locus overlaps the non-syndromic deafness locus DFNB48 raising the possibility that the two disorders may be caused by allelic mutations.

Mutations within the nuclear localization signal of the porcine reproductive and respiratory syndrome virus nucleocapsid protein attenuate virus replication

International Nuclear Information System (INIS)

Lee, Changhee; Hodgins, Douglas; Calvert, Jay G.; Welch, Siao-Kun W.; Jolie, Rika; Yoo, Dongwan

2006-01-01

Porcine reproductive and respiratory syndrome virus (PRRSV) is an RNA virus replicating in the cytoplasm, but the nucleocapsid (N) protein is specifically localized to the nucleus and nucleolus in virus-infected cells. A 'pat7' motif of 41-PGKK(N/S)KK has previously been identified in the N protein as the functional nuclear localization signal (NLS); however, the biological consequences of N protein nuclear localization are unknown. In the present study, the role of N protein nuclear localization during infection was investigated in pigs using an NLS-null mutant virus. When two lysines at 43 and 44 at the NLS locus were substituted to glycines, the modified NLS with 41-PGGGNKK restricted the N protein to the cytoplasm. This NLS-null mutation was introduced into a full-length infectious cDNA clone of PRRSV. Upon transfection of cells, the NLS-null full-length clone induced cytopathic effects and produced infectious progeny. The NLS-null virus grew to a titer 100-fold lower than that of wild-type virus. To examine the response to NLS-null PRRSV in the natural host, three groups of pigs, consisting of seven animals per group, were intranasally inoculated with wild-type, placebo, or NLS-null virus, and the animals were maintained for 4 weeks. The NLS-null-infected pigs had a significantly shorter mean duration of viremia than wild-type-infected pigs but developed significantly higher titers of neutralizing antibodies. Mutations occurred at the NLS locus in one pig during viremia, and four types of mutations were identified: 41-PGRGNKK, 41-PGGRNKK, and 41-PGRRNKK, and 41-PGKKSKK. Both wild-type and NLS-null viruses persisted in the tonsils for at least 4 weeks, and the NLS-null virus persisting in the tonsils was found to be mutated to either 41-PGRGNKK or 41-PGGRNKK in all pigs. No other mutation was found in the N gene. All types of reversions which occurred during viremia and persistence were able to translocate the mutated N proteins to the nucleus, indicating a

Mutational analysis and genetic cloning of the agnostic locus, which regulates learning ability in Drosophila.

Science.gov (United States)

Peresleni, A I; Savvateeva, E V; Peresleni, I V; Sharagina, L M

1997-01-01

P-insertion mutations were obtained and localized by in situ methods at the agnostic gene (agn: 1-38.9; 11AB) in Drosophila. All agn mutants showed a wide spectrum of pleiotropic effects: an EMS-induced mutation of the agn-ts398 improved the ability to develop a conditioned defensive response and increased the activity of cAMP metabolic enzymes; spontaneous mutation of agnX1 showed morphological defects of the brain. P-insertion mutations were used to clone the gene; a restriction map of 80 kb in length was determined, and the insertion was localized to a fragment of 9 kb.

Tbc1d1 mutation in lean mouse strain confers leanness and protects from diet-induced obesity

DEFF Research Database (Denmark)

Chadt, Alexandra; Leicht, Katja; Deshmukh, Atul

2008-01-01

We previously identified Nob1 as a quantitative trait locus for high-fat diet-induced obesity and diabetes in genome-wide scans of outcross populations of obese and lean mouse strains. Additional crossbreeding experiments indicated that Nob1 represents an obesity suppressor from the lean Swiss Jim...... Lambert (SJL) strain. Here we identify a SJL-specific mutation in the Tbc1d1 gene that results in a truncated protein lacking the TBC Rab-GTPase-activating protein domain. TBC1D1, which has been recently linked to human obesity, is related to the insulin signaling protein AS160 and is predominantly...... and reduced glucose uptake in isolated skeletal muscle. Our data strongly suggest that mutation of Tbc1d1 suppresses high-fat diet-induced obesity by increasing lipid use in skeletal muscle....

Mutation screening and association analysis of six candidate genes for autism on chromosome 7q

DEFF Research Database (Denmark)

Bonora, E.; Lamb, J.A.; Barnby, G.

2005-01-01

in the genes CUTL1, LAMB1 and PTPRZ1. Analysis of genetic variants provided evidence for association with autism for one of the new missense changes identified in LAMB1; this effect was stronger in a subgroup of affected male sibling pair families, implying a possible specific sex-related effect......Genetic studies have provided evidence for an autism susceptibility locus (AUTS1) on chromosome 7q. Screening for mutations in six genes mapping to 7q, CUTL1, SRPK2, SYPL, LAMB1, NRCAM and PTPRZ1 in 48 unrelated individuals with autism led to the identification of several new coding variants...

Projection specificity in heterogeneous locus coeruleus cell populations: implications for learning and memory

Science.gov (United States)

Uematsu, Akira; Tan, Bao Zhen

2015-01-01

Noradrenergic neurons in the locus coeruleus (LC) play a critical role in many functions including learning and memory. This relatively small population of cells sends widespread projections throughout the brain including to a number of regions such as the amygdala which is involved in emotional associative learning and the medial prefrontal cortex which is important for facilitating flexibility when learning rules change. LC noradrenergic cells participate in both of these functions, but it is not clear how this small population of neurons modulates these partially distinct processes. Here we review anatomical, behavioral, and electrophysiological studies to assess how LC noradrenergic neurons regulate these different aspects of learning and memory. Previous work has demonstrated that subpopulations of LC noradrenergic cells innervate specific brain regions suggesting heterogeneity of function in LC neurons. Furthermore, noradrenaline in mPFC and amygdala has distinct effects on emotional learning and cognitive flexibility. Finally, neural recording data show that LC neurons respond during associative learning and when previously learned task contingencies change. Together, these studies suggest a working model in which distinct and potentially opposing subsets of LC neurons modulate particular learning functions through restricted efferent connectivity with amygdala or mPFC. This type of model may provide a general framework for understanding other neuromodulatory systems, which also exhibit cell type heterogeneity and projection specificity. PMID:26330494

Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

NARCIS (Netherlands)

K. Lawrenson (Kate); S. Kar (Siddhartha); K. McCue (Karen); Kuchenbaeker, K. (Karoline); K. Michailidou (Kyriaki); J.P. Tyrer (Jonathan); J. Beesley (Jonathan); S.J. Ramus (Susan); Li, Q. (Qiyuan); Delgado, M.K. (Melissa K.); J.M. Lee (Janet M.); K. Aittomäki (Kristiina); I.L. Andrulis (Irene); H. Anton-Culver (Hoda); Arndt, V. (Volker); B.K. Arun (Banu); B. Arver (Brita Wasteson); E.V. Bandera (Elisa); M. Barile (Monica); Barkardottir, R.B. (Rosa B.); D. Barrowdale (Daniel); M.W. Beckmann (Matthias); J. Benítez (Javier); A. Berchuck (Andrew); M. Bisogna (Maria); L. Bjorge (Line); C. Blomqvist (Carl); W.J. Blot (William); N.V. Bogdanova (Natalia); Bojesen, A. (Anders); S.E. Bojesen (Stig); M.K. Bolla (Manjeet K.); B. Bonnani (Bernardo); A.-L. Borresen-Dale (Anne-Lise); H. Brauch (Hiltrud); P. Brennan (Paul); H. Brenner (Hermann); F. Bruinsma (Fiona); J. Brunet (Joan); S.A.B.S. Buhari (Shaik Ahmad Bin Syed); B. Burwinkel (Barbara); R. Butzow (Ralf); S.S. Buys (Saundra); Q. Cai (Qiuyin); T. Caldes (Trinidad); I. Campbell (Ian); Canniotto, R. (Rikki); J. Chang-Claude (Jenny); Chiquette, J. (Jocelyne); Choi, J.-Y. (Ji-Yeob); K.B.M. Claes (Kathleen B.M.); L.S. Cook (Linda S.); A. Cox (Angela); D.W. Cramer (Daniel); S.S. Cross (Simon); C. Cybulski (Cezary); K. Czene (Kamila); M.B. Daly (Mary B.); F. Damiola (Francesca); A. Dansonka-Mieszkowska (Agnieszka); H. Darabi (Hatef); J. Dennis (Joe); P. Devilee (Peter); O. Díez (Orland); J.A. Doherty (Jennifer A.); S.M. Domchek (Susan); C.M. Dorfling (Cecilia); T. Dörk (Thilo); M. Dumont (Martine); H. Ehrencrona (Hans); B. Ejlertsen (Bent); S.D. Ellis (Steve); C. Engel (Christoph); E. Lee (Eunjung); Evans, D.G. (D. Gareth); P.A. Fasching (Peter); L. Feliubadaló (L.); J.D. Figueroa (Jonine); D. Flesch-Janys (Dieter); O. Fletcher (Olivia); H. Flyger (Henrik); L. Foretova (Lenka); F. Fostira (Florentia); W.D. Foulkes (William); B.L. Fridley (Brooke); E. Friedman (Eitan); D. Frost (Debra); Gambino, G. (Gaetana); P.A. Ganz (Patricia A.); J. Garber (Judy); M. García-Closas (Montserrat); A. Gentry-Maharaj (Aleksandra); M. Ghoussaini (Maya); G.G. Giles (Graham); R. Glasspool (Rosalind); A.K. Godwin (Andrew K.); M.S. Goldberg (Mark); D. Goldgar (David); A. González-Neira (Anna); E.L. Goode (Ellen); M.T. Goodman (Marc); M.H. Greene (Mark H.); J. Gronwald (Jacek); P. Guénel (Pascal); C.A. Haiman (Christopher A.); P. Hall (Per); Hallberg, E. (Emily); U. Hamann (Ute); T.V.O. Hansen (Thomas); P. harrington (Patricia); J.M. Hartman (Joost); N. Hassan (Norhashimah); S. Healey (Sue); P.U. Heitz; J. Herzog (Josef); E. Høgdall (Estrid); C.K. Høgdall (Claus); F.B.L. Hogervorst (Frans); A. Hollestelle (Antoinette); J.L. Hopper (John); P.J. Hulick (Peter); T. Huzarski (Tomasz); E.N. Imyanitov (Evgeny); C. Isaacs (Claudine); H. Ito (Hidemi); A. Jakubowska (Anna); R. Janavicius (Ramunas); A. Jensen (Allan); E.M. John (Esther); Johnson, N. (Nichola); M. Kabisch (Maria); D. Kang (Daehee); M.K. Kapuscinski (Miroslav K.); Karlan, B.Y. (Beth Y.); S. Khan (Sofia); L.A.L.M. Kiemeney (Bart); M. Kjaer (Michael); J.A. Knight (Julia); I. Konstantopoulou (I.); V-M. Kosma (Veli-Matti); V. Kristensen (Vessela); J. Kupryjanczyk (Jolanta); A. Kwong (Ava); M. de La Hoya (Miguel); Y. Laitman (Yael); Lambrechts, D. (Diether); N.D. Le (Nhu D.); K. De Leeneer (Kim); K.J. Lester (Kathryn); D.A. Levine (Douglas); J. Li (Jingmei); A. Lindblom (Annika); J. Long (Jirong); A. Lophatananon (Artitaya); J.T. Loud (Jennifer); K.H. Lu (Karen); J. Lubinski (Jan); A. Mannermaa (Arto); S. Manoukian (Siranoush); L. Le Marchand (Loic); S. Margolin (Sara); F. Marme (Frederick); L.F. Massuger (Leon); K. Matsuo (Keitaro); S. Mazoyer (Sylvie); L. McGuffog (Lesley); C.A. McLean (Catriona Ann); I. McNeish (Iain); A. Meindl (Alfons); U. Menon (Usha); Mensenkamp, A.R. (Arjen R.); R.L. Milne (Roger); M. Montagna (Marco); K.B. Moysich (Kirsten); K.R. Muir (K.); A.-M. Mulligan (Anna-Marie); K.L. Nathanson (Katherine); R.B. Ness (Roberta); S.L. Neuhausen (Susan); H. Nevanlinna (Heli); S. Nord (Silje); R.L. Nussbaum (Robert L.); K. Odunsi (Kunle); K. Offit (Kenneth); E. Olah; O.I. Olopade (Olufunmilayo I.); J.E. Olson (Janet); C. Olswold (Curtis); D.M. O'Malley (David M.); I. Orlow (Irene); N. Orr (Nick); A. Osorio (Ana); Park, S.K. (Sue Kyung); C.L. Pearce (Celeste); T. Pejovic (Tanja); P. Peterlongo (Paolo); G. Pfeiler (Georg); C. Phelan (Catherine); E.M. Poole (Elizabeth); K. Pykäs (Katri); P. Radice (Paolo); J. Rantala (Johanna); M.U. Rashid (Muhammad); G. Rennert (Gad); V. Rhenius (Valerie); K. Rhiem (Kerstin); H. Risch (Harvey); G.C. Rodriguez (Gustavo); M.A. Rossing (Mary Anne); Rudolph, A. (Anja); H.B. Salvesen (Helga); Sangrajrang, S. (Suleeporn); Sawyer, E.J. (Elinor J.); J.M. Schildkraut (Joellen); M.K. Schmidt (Marjanka); R.K. Schmutzler (Rita); T.A. Sellers (Thomas A.); C.M. Seynaeve (Caroline); Shah, M. (Mitul); C.-Y. Shen (Chen-Yang); X.-O. Shu (Xiao-Ou); W. Sieh (Weiva); C.F. Singer (Christian); O. Sinilnikova (Olga); S. Slager (Susan); H. Song (Honglin); Soucy, P. (Penny); M.C. Southey (Melissa); M. Stenmark-Askmalm (Marie); D. Stoppa-Lyonnet (Dominique); C. Sutter (Christian); A.J. Swerdlow (Anthony ); Tchatchou, S. (Sandrine); P.J. Teixeira; S.-H. Teo (Soo-Hwang); K.L. Terry (Kathryn); M.B. Terry (Mary Beth); M. Thomassen (Mads); M.G. Tibiletti (Maria Grazia); L. Tihomirova (Laima); S. Tognazzo (Silvia); A.E. Toland (Amanda); I.P. Tomlinson (Ian); D. Torres (Diana); T. Truong (Thérèse); C.-C. Tseng (Chiu-Chen); N. Tung (Nadine); Tworoger, S.S. (Shelley S.); C. Vachon (Celine); Van Den Ouweland, A.M.W. (Ans M.W.); Van Doorn, H.C. (Helena C.); E.J. van Rensburg (Elizabeth); L.J. van 't Veer (Laura); A. Vanderstichele (Adriaan); I. Vergote (Ignace); J. Vijai (Joseph); Wang, Q. (Qin); S. Wang-Gohrke (Shan); J.N. Weitzel (Jeffrey); N. Wentzensen (N.); A.S. Whittemore (Alice); H. Wildiers (Hans); R. Winqvist (Robert); A.H. Wu (Anna); Yannoukakos, D. (Drakoulis); S.-Y. Yoon (Sook-Yee); J-C. Yu (Jyh-Cherng); W. Zheng (Wei); Y. Zheng (Ying); Khanna, K.K. (Kum Kum); J. Simard (Jacques); A.N.A. Monteiro (Alvaro N.); J.D. French (Juliet); F.J. Couch (Fergus); M. Freedman (Matthew); D.F. Easton (Douglas F.); A.M. Dunning (Alison); P.D.P. Pharoah (Paul); S.L. Edwards (Stacey); G. Chenevix-Trench (Georgia); A.C. Antoniou (Antonis C.); S.A. Gayther (Simon); D. Bowtell (David); A. DeFazio (Anna); P. Webb (Penny); M.-A. Collonge-Rame; Damette, A. (Alexandre); E. Barouk-Simonet (Emmanuelle); F. Bonnet (Françoise); V. Bubien (Virginie); N. Sevenet (Nicolas); M. Longy (Michel); P. Berthet (Pascaline); D. Vaur (Dominique); L. Castera (Laurent); S.F. Ferrer; Y.-J. Bignon (Yves-Jean); N. Uhrhammer (Nancy); F. Coron (Fanny); L. Faivre (Laurence); Baurand, A. (Amandine); Jacquot, C. (Caroline); Bertolone, G. (Geoffrey); Lizard, S. (Sarab); D. Leroux (Dominique); H. Dreyfus (Hélène); C. Rebischung (Christine); Peysselon, M. (Magalie); J.-P. Peyrat; J. Fournier (Joëlle); F. Révillion (Françoise); C. Adenis (Claude); L. Vénat-Bouvet (Laurence); M. Léone (Mélanie); N. Boutry-Kryza (N.); A. Calender (Alain); S. Giraud (Sophie); C. Verny-Pierre (Carole); C. Lasset (Christine); V. Bonadona (Valérie); Barjhoux, L. (Laure); H. Sobol (Hagay); V. Bourdon (Violaine); Noguchi, T. (Tetsuro); A. Remenieras (Audrey); I. Coupier (Isabelle); P. Pujol (Pascal); J. Sokolowska (Johanna); M. Bronner (Myriam); C.D. Delnatte (Capucine); Bézieau, S. (Stéphane); Mari, V. (Véronique); M. Gauthier-Villars (Marion); B. Buecher (Bruno); E. Rouleau (Etienne); L. Golmard (Lisa); V. Moncoutier (Virginie); M. Belotti (Muriel); A. de Pauw (Antoine); Elan, C. (Camille); Fourme, E. (Emmanuelle); Birot, A.-M. (Anne-Marie); Saule, C. (Claire); Laurent, M. (Maïté); C. Houdayer (Claude); F. Lesueur (Fabienne); N. Mebirouk (Noura); F. Coulet (Florence); C. Colas (Chrystelle); F. Soubrier; Warcoin, M. (Mathilde); F. Prieur (Fabienne); M. Lebrun (Marine); C. Kientz (Caroline); D.W. Muller (Danièle); J.P. Fricker (Jean Pierre); C. Toulas (Christine); R. Guimbaud (Rosine); L. Gladieff (Laurence); V. Feillel (Viviane); I. Mortemousque (Isabelle); B. Bressac-de Paillerets (Brigitte); O. Caron (Olivier); M. Guillaud-Bataille (Marine); H. Gregory (Helen); Z. Miedzybrodzka (Zosia); P.J. Morrison (Patrick); A. Donaldson (Alan); M.T. Rogers (Mark); M.J. Kennedy (John); M.E. Porteous (Mary); A. Brady (A.); J. Barwell (Julian); Foo, C. (Claire); F. Lalloo (Fiona); L. Side (Lucy); J. Eason (Jacqueline); Henderson, A. (Alex); L.J. Walker (Lisa); J. Cook (Jackie); Snape, K. (Katie); A. Murray (Alexandra); E. McCann (Emma); M.A. Rookus (Matti); F.E. van Leeuwen (F.); L. van der Kolk (Lizet); M.K. Schmidt (Marjanka); N.S. Russell (Nicola); J.L. de Lange (J.); Wijnands, R.; J.M. Collée (Margriet); M.J. Hooning (Maartje); Seynaeve, C.; C.H.M. van Deurzen (Carolien); A.I.M. Obdeijn (Inge-Marie); C.J. van Asperen (Christi); R.A.E.M. Tollenaar (Rob); T.C.T.E.F. van Cronenburg; C.M. Kets; M.G.E.M. Ausems (Margreet); C. van der Pol (Carmen); T.A.M. van Os (Theo); Q. Waisfisz (Quinten); E.J. Meijers-Heijboer (Hanne); E.B. Gómez García (Encarna); J.C. Oosterwijk (Jan); M.J. Mourits (Marjan); G.H. de Bock (Geertruida); H. Vasen (Hans); Siesling, S.; Verloop, J.; L.I.H. Overbeek (Lucy); S.B. Fox (Stephen); J. Kirk (Judy); G.J. Lindeman; M. Price (Melanie)

2016-01-01

textabstractA locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 ×

Is Increased Low-dose somatic Radiosensitivity Associated with Increased Transgenerational Germline Mutation

International Nuclear Information System (INIS)

Brenner, David J.

2008-01-01

Using single-molecule polymerase chain reaction, the frequency of spontaneous and radiation-induced mutation at an expanded simple tandem repeat (ESTR) locus was studied in DNA samples extracted from sperm and bone marrow of Atm knockout (Atm+/-) heterozygous male mice. The frequency of spontaneous mutation in sperm and bone marrow in Atm+/- males did not significantly differ from that in wild-type BALB/c mice. Acute gamma-ray exposure did not affect ESTR mutation frequency in bone marrow and resulted in similar increases in sperm samples taken from Atm+/- and BALB/c males. Taken together, these results suggest that the Atm haploinsufficiency analyzed in our study does not affect spontaneous and radiation-induced ESTR mutation frequency in mice

Locus of Control, Perceptions and Attributions of Student Teachers in Educational Situations.

Science.gov (United States)

Kremer, Lya; Kurtz, Chaya

Student teachers' perceptions of locus of control was investigated. Locus of control is defined as representing the extent of dependence upon inner or outer forces, the extent one is willing to invest in shaping the environment, and the perception of reinforcement as dependent upon those efforts, or upon random events. The specific questions were:…

Protein-truncating mutations in ASPM cause variable reduction in brain size

NARCIS (Netherlands)

Bond, Jacquelyn; Scott, Sheila; Hampshire, Daniel J.; Springell, Kelly; Corry, Peter; Abramowicz, Marc J.; Mochida, Ganesh H.; Hennekam, Raoul C. M.; Maher, Eamonn R.; Fryns, Jean-Pierre; Alswaid, Abdulrahman; Jafri, Hussain; Rashid, Yasmin; Mubaidin, Ammar; Walsh, Christopher A.; Roberts, Emma; Woods, C. Geoffrey

2003-01-01

Mutations in the ASPM gene at the MCPH5 locus are expected to be the most common cause of human autosomal recessive primary microcephaly (MCPH), a condition in which there is a failure of normal fetal brain development, resulting in congenital microcephaly and mental retardation. We have performed

Artemisinin Resistance-Associated Polymorphisms at the K13-Propeller Locus Are Absent in Plasmodium falciparum Isolates from Haiti

Science.gov (United States)

Carter, Tamar E.; Boulter, Alexis; Existe, Alexandre; Romain, Jean R.; St. Victor, Jean Yves; Mulligan, Connie J.; Okech, Bernard A.

2015-01-01

Antimalarial drugs are a key tool in malaria elimination programs. With the emergence of artemisinin resistance in southeast Asia, an effort to identify molecular markers for surveillance of resistant malaria parasites is underway. Non-synonymous mutations in the kelch propeller domain (K13-propeller) in Plasmodium falciparum have been associated with artemisinin resistance in samples from southeast Asia, but additional studies are needed to characterize this locus in other P. falciparum populations with different levels of artemisinin use. Here, we sequenced the K13-propeller locus in 82 samples from Haiti, where limited government oversight of non-governmental organizations may have resulted in low-level use of artemisinin-based combination therapies. We detected a single-nucleotide polymorphism (SNP) at nucleotide 1,359 in a single isolate. Our results contribute to our understanding of the global genomic diversity of the K13-propeller locus in P. falciparum populations. PMID:25646258

USH1K, a novel locus for type I Usher syndrome, maps to chromosome 10p11.21-q21.1.

Science.gov (United States)

Jaworek, Thomas J; Bhatti, Rashid; Latief, Noreen; Khan, Shaheen N; Riazuddin, Saima; Ahmed, Zubair M

2012-10-01

We ascertained two large Pakistani consanguineous families (PKDF231 and PKDF608) segregating profound hearing loss, vestibular dysfunction, and retinitis pigmentosa; the defining features of Usher syndrome type 1 (USH1). To date, seven USH1 loci have been reported. Here, we map a novel locus, USH1K, on chromosome 10p11.21-q21.1. In family PKDF231, we performed a genome-wide linkage screen and found a region of homozygosity shared among the affected individuals at chromosome 10p11.21-q21.1. Meiotic recombination events in family PKDF231 define a critical interval of 11.74 cM (20.20 Mb) bounded by markers D10S1780 (63.83 cM) and D10S546 (75.57 cM). Affected individuals of family PKDF608 were also homozygous for chromosome 10p11.21-q21.1-linked STR markers. Of the 85 genes within the linkage interval, PCDH15, GJD4, FZD4, RET and LRRC18 were sequenced in both families, but no potential pathogenic mutation was identified. The USH1K locus overlaps the non-syndromic deafness locus DFNB33 raising the possibility that the two disorders may be caused by allelic mutations.

Mutations in SYNGAP1 Cause Intellectual Disability, Autism, and a Specific Form of Epilepsy by Inducing Haploinsufficiency

DEFF Research Database (Denmark)

Berryer, Martin H; Hamdan, Fadi F; Klitten, Laura L

2013-01-01

De novo mutations in SYNGAP1, which codes for a RAS/RAP GTP-activating protein, cause nonsyndromic intellectual disability (NSID). All disease-causing point mutations identified until now in SYNGAP1 are truncating, raising the possibility of an association between this type of mutations and NSID...... also showed ataxia, autism, and a specific form of generalized epilepsy that can be refractory to treatment. All of these mutations occurred de novo, except c.283dupC, which was inherited from a father who is a mosaic. Biolistic transfection of wild-type SYNGAP1 in pyramidal cells from cortical...

Compound Heterozygosity for Null Mutations and a Common Hypomorphic Risk Haplotype in TBX6 Causes Congenital Scoliosis.

Science.gov (United States)

Takeda, Kazuki; Kou, Ikuyo; Kawakami, Noriaki; Iida, Aritoshi; Nakajima, Masahiro; Ogura, Yoji; Imagawa, Eri; Miyake, Noriko; Matsumoto, Naomichi; Yasuhiko, Yukuto; Sudo, Hideki; Kotani, Toshiaki; Nakamura, Masaya; Matsumoto, Morio; Watanabe, Kota; Ikegawa, Shiro

2017-03-01

Congenital scoliosis (CS) occurs as a result of vertebral malformations and has an incidence of 0.5-1/1,000 births. Recently, TBX6 on chromosome 16p11.2 was reported as a disease gene for CS; about 10% of Chinese CS patients were compound heterozygotes for rare null mutations and a common haplotype defined by three SNPs in TBX6. All patients had hemivertebrae. We recruited 94 Japanese CS patients, investigated the TBX6 locus for both mutations and the risk haplotype, examined transcriptional activities of mutant TBX6 in vitro, and evaluated clinical and radiographic features. We identified TBX6 null mutations in nine patients, including a missense mutation that had a loss of function in vitro. All had the risk haplotype in the opposite allele. One of the mutations showed dominant negative effect. Although all Chinese patients had one or more hemivertebrae, two Japanese patients did not have hemivertebra. The compound heterozygosity of null mutations and the common risk haplotype in TBX6 also causes CS in Japanese patients with similar incidence. Hemivertebra was not a specific type of spinal malformation in TBX6-associated CS (TACS). A heterozygous TBX6 loss-of-function mutation has been reported in a family with autosomal-dominant spondylocostal dysostosis, but it may represent a spectrum of the same disease with TACS. © 2017 WILEY PERIODICALS, INC.

ATRX mutation in two adult brothers with non-specific moderate intellectual disability identified by exome sequencing.

Science.gov (United States)

Moncini, S; Bedeschi, M F; Castronovo, P; Crippa, M; Calvello, M; Garghentino, R R; Scuvera, G; Finelli, P; Venturin, M

2013-12-01

In this report, we describe two adult brothers affected by moderate non-specific intellectual disability (ID). They showed minor facial anomalies, not clearly ascribable to any specific syndromic patterns, microcephaly, brachydactyly and broad toes. Both brothers presented seizures. Karyotype, subtelomeric and FMR1 analysis were normal in both cases. We performed array-CGH analysis that revealed no copy-number variations potentially associated with ID. Subsequent exome sequence analysis allowed the identification of the ATRX c.109C>T (p.R37X) mutation in both the affected brothers. Sanger sequencing confirmed the presence of the mutation in the brothers and showed that the mother is a healthy carrier. Mutations in the ATRX gene cause the X-linked alpha thalassemia/mental retardation (ATR-X) syndrome (MIM #301040), a severe clinical condition usually associated with profound ID, facial dysmorphism and alpha thalassemia. However, the syndrome is clinically heterogeneous and some mutations, including the c.109C>T, are associated with a broad phenotypic spectrum, with patients displaying a less severe phenotype with only mild-moderate ID. In the case presented here, exome sequencing provided an effective strategy to achieve the molecular diagnosis of ATR-X syndrome, which otherwise would have been difficult to consider due to the mild non-specific phenotype and the absence of a family history with typical severe cases.

USP7 Is a Tumor-Specific WNT Activator for APC-Mutated Colorectal Cancer by Mediating β-Catenin Deubiquitination

Directory of Open Access Journals (Sweden)

Laura Novellasdemunt

2017-10-01

Full Text Available The tumor suppressor gene adenomatous polyposis coli (APC is mutated in most colorectal cancers (CRCs, resulting in constitutive Wnt activation. To understand the Wnt-activating mechanism of the APC mutation, we applied CRISPR/Cas9 technology to engineer various APC-truncated isogenic lines. We find that the β-catenin inhibitory domain (CID in APC represents the threshold for pathological levels of Wnt activation and tumor transformation. Mechanistically, CID-deleted APC truncation promotes β-catenin deubiquitination through reverse binding of β-TrCP and USP7 to the destruction complex. USP7 depletion in APC-mutated CRC inhibits Wnt activation by restoring β-catenin ubiquitination, drives differentiation, and suppresses xenograft tumor growth. Finally, the Wnt-activating role of USP7 is specific to APC mutations; thus, it can be used as a tumor-specific therapeutic target for most CRCs.

The LOCUS interface to the MFE database

International Nuclear Information System (INIS)

Miner, W.H. Jr.

1991-01-01

The MFE database now consists of over 900 shots from TFTR, PDX, PLT, T-10, JT-60, TEXT, JET and ASDEX. A variety of discharge conditions is represented, ranging from single time slice Ohmic discharges to multiple time-slice auxiliary heated discharges. Included with most datasets is a reference that describes the experiment being performed when the data was taken. The MFE database is currently implemented under INGRES on a VAX that is on Internet. LOCUS, a database utility, developed at the Princeton Plasma Physics Laboratory is now available as an interface to the database. The LOCUS front end provides a graphic interface to the database from any generic graphics terminal that supports Tektronix 4010 emulation. It provides a variety of procedures for extracting, manipulating and graphing data from the MFE database. In order to demonstrate the capabilities of the LOCUS interface, the authors examine, in detail, one of the recently added JET, H-mode discharges. In this example, they address some new concepts such as monitor functions, which have been introduced in order to help users more fully understand the multiple time-slice datasets. They also describe some of the more advanced techniques available in LOCUS for data access and manipulation. Specific areas of interest that are discussed are searching for and retrieving datasets, graphics, data fitting, and linear regression analysis

Mutation rate heterogeneity and the generation of allele diversity at the human minisatellite MS205 (D16S309).

Science.gov (United States)

May, C A; Jeffreys, A J; Armour, J A

1996-11-01

Many tandemly repeated minisatellite loci display extreme levels of length variation as a consequence of high rates of spontaneous germline mutation altering repeat copy number. Direct screening for new allele lengths by small-pool PCR has shown that instability at the human minisatellite locus MS205 (D16S309) is largely germline specific and usually results in the gain or loss of just a few repeat units. Structural analysis of the order of variant repeats has shown that these events occur preferentially at one end of the tandem array and can result in complex rearrangements including the inter-allelic transfer of repeat units. In contrast, putative mutants recovered from somatic DNA occur at a substantially lower rate and are simple and non-polar in nature. Germline mutation rates vary considerably between alleles, consistent with regulation occurring in cis. Although examination of DNA sequence polymorphisms immediately flanking the minisatellite reveals no definitive associations with germline mutation rate variation, differences in rate may be paralleled by changes in mutation spectrum. These findings help to explain the diversity of MS205 allele structures in modern humans and suggest a common mutation pathway with some other minisatellites.

A novel HSF4 gene mutation (p.R405X causing autosomal recessive congenital cataracts in a large consanguineous family from Pakistan

Directory of Open Access Journals (Sweden)

Cheema Abdul

2008-11-01

Full Text Available Abstract Background Hereditary cataracts are most frequently inherited as autosomal dominant traits, but can also be inherited in an autosomal recessive or X-linked fashion. To date, 12 loci for autosomal recessive cataracts have been mapped including a locus on chromosome 16q22 containing the disease-causing gene HSF4 (Genbank accession number NM_001040667. Here, we describe a family from Pakistan with the first nonsense mutation in HSF4 thus expanding the mutational spectrum of this heat shock transcription factor gene. Methods A large consanguineous Pakistani family with autosomal recessive cataracts was collected from Quetta. Genetic linkage analysis was performed for the common known autosomal recessive cataracts loci and linkage to a locus containing HSF4 (OMIM 602438 was found. All exons and adjacent splice sites of the heat shock transcription factor 4 gene (HSF4 were sequenced. A mutation-specific restriction enzyme digest (HphI was performed for all family members and unrelated controls. Results The disease phenotype perfectly co-segregated with markers flanking the known cataract gene HSF4, whereas other autosomal recessive loci were excluded. A maximum two-point LOD score with a Zmax = 5.6 at θ = 0 was obtained for D16S421. Direct sequencing of HSF4 revealed the nucleotide exchange c.1213C > T in this family predicting an arginine to stop codon exchange (p.R405X. Conclusion We identified the first nonsense mutation (p.R405X in exon 11 of HSF4 in a large consanguineous Pakistani family with autosomal recessive cataract.

Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

DEFF Research Database (Denmark)

Lawrenson, Kate; Kar, Siddhartha; McCue, Karen

2016-01-01

A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10(-20)), ER-n...

Concomitant BCORL1 and BRAF Mutations in Vemurafenib-Resistant Melanoma Cells

Directory of Open Access Journals (Sweden)

Luca Mologni

2018-05-01

Full Text Available BRAF is the most frequently mutated gene in melanoma. Constitutive activation of mutant BRAFV600E leads to aberrant Ras-independent MAPK signaling and cell transformation. Inhibition of mutant BRAF is a current frontline therapy for such cases, with improved survival compared with chemotherapy. Unfortunately, reactivation of MAPK signaling by several mechanisms has been shown to cause drug resistance and disease recurrence. In this work, we describe the co-occurrence of an in-frame deletion within an amplified BRAFV600E locus and a missense point mutation of the transcriptional repressor BCORL1 in vemurafenib-resistant A375 melanoma cells. Functional data confirmed that truncated p47BRAFV600E and mutant BCORL1Q1076H both contribute to resistance. Interestingly, either endogenous BCORL1 silencing or ectopic BCORL1Q1076H expression mimicked the effects of a CRISPR/Cas9-edited BCORL1Q1076H locus, suggesting a complex mixture of loss- and gain-of-function effects caused by the mutation. Transcriptomic data confirmed this hypothesis. Finally, we show that the pan-RAF inhibitor sorafenib is not affected by expression of BRAF deletion variant and effectively synergizes with vemurafenib to block resistant cells, suggesting a possible intervention for this class of mutants.

DFNB79: reincarnation of a nonsyndromic deafness locus on chromosome 9q34.3.

Science.gov (United States)

Khan, Shahid Yar; Riazuddin, Saima; Shahzad, Mohsin; Ahmed, Nazir; Zafar, Ahmad Usman; Rehman, Atteeq Ur; Morell, Robert J; Griffith, Andrew J; Ahmed, Zubair M; Riazuddin, Sheikh; Friedman, Thomas B

2010-01-01

Genetic analysis of an inbred Pakistani family PKDF280, segregating prelingual severe to profound sensorineural hearing loss, provided evidence for a DFNB locus on human chromosome 9q34.3. Co-segregation of the deafness trait with marker D9SH159 was determined by a two-point linkage analysis (LOD score 9.43 at theta=0). Two additional large families, PKDF517 and PKDF741, co-segregate recessive deafness with markers linked to the same interval. Haplotype analyses of these three families refined the interval to 3.84 Mb defined by D9S1818 (centromeric) and D9SH6 (telomeric). This interval overlaps with the previously reported DFNB33 locus whose chromosomal map position has been recently revised and assigned to a new position on chromosome 10p11.23-q21.1. The nonsyndromic deafness locus on chromosome 9q segregating in family PKDF280 was designated DFNB79. We are currently screening the 113 candidate DFNB79 genes for mutations and have excluded CACNA1B, EDF1, PTGDS, EHMT1, QSOX2, NOTCH1, MIR126 and MIR602.

The allele-frequency spectrum in a decoupled Moran model with mutation, drift, and directional selection, assuming small mutation rates.

Science.gov (United States)

Vogl, Claus; Clemente, Florian

2012-05-01

We analyze a decoupled Moran model with haploid population size N, a biallelic locus under mutation and drift with scaled forward and backward mutation rates θ(1)=μ(1)N and θ(0)=μ(0)N, and directional selection with scaled strength γ=sN. With small scaled mutation rates θ(0) and θ(1), which is appropriate for single nucleotide polymorphism data in highly recombining regions, we derive a simple approximate equilibrium distribution for polymorphic alleles with a constant of proportionality. We also put forth an even simpler model, where all mutations originate from monomorphic states. Using this model we derive the sojourn times, conditional on the ancestral and fixed allele, and under equilibrium the distributions of fixed and polymorphic alleles and fixation rates. Furthermore, we also derive the distribution of small samples in the diffusion limit and provide convenient recurrence relations for calculating this distribution. This enables us to give formulas analogous to the Ewens-Watterson estimator of θ for biased mutation rates and selection. We apply this theory to a polymorphism dataset of fourfold degenerate sites in Drosophila melanogaster. Copyright © 2012 Elsevier Inc. All rights reserved.

ARL6IP6, a susceptibility locus for ischemic stroke, is mutated in a patient with syndromic Cutis Marmorata Telangiectatica Congenita.

Science.gov (United States)

Abumansour, Iman S; Hijazi, Hadia; Alazmi, Anas; Alzahrani, Fatma; Bashiri, Fahad A; Hassan, Hamdy; Alhaddab, Mohammed; Alkuraya, Fowzan S

2015-08-01

Cutis Marmorata Telangiectatica Congenita (CMTC) is a congenital localized or generalized vascular anomaly, usually sporadic in occurrence. It can be associated with other cutaneous or systemic manifestations. About 300 cases have been reported. The molecular etiology remains largely unknown. The main purpose of this study is to delineate the molecular basis for a syndromic CMTC phenotype in a consanguineous Saudi family. Clinical phenotyping including detailed neurological imaging, followed by autozygosity mapping and trio whole exome sequencing (WES) are also studied. We have identified a homozygous truncating mutation in ARL6IP6 as the likely cause of a syndromic form of CMTC associated with major dysmorphism, developmental delay, transient ischemic attacks and cerebral vascular malformations. This gene was previously implicated by genome wide association study (GWAS) as a susceptibility locus to ischemic stroke in young adults. We identify ARL6IP6 as a novel candidate gene for a syndromic form of CMTC. This suggests that ischemic stroke or transient ischemic attacks (TIA) may represent, at least in some cases, the mild end of a phenotypic spectrum that has at its severe end autosomal recessive CMTC. This finding contributes to a growing appreciation of the continuum of Mendelian and common complex diseases.

Screening individuals with intellectual disability, autism and Tourette's syndrome for KCNK9 mutations and aberrant DNA methylation within the 8q24 imprinted cluster

DEFF Research Database (Denmark)

Delgado, Marta Sánchez; Camprubí, Cristina; Tümer, Zeynep

2014-01-01

The phenotype overlap between autism spectrum disorders (ASD) & intellectual disabilities (ID) is mirrored at the genetic level, with common genes being reported mutated in variety of developmental disabilities. However despite widespread genetic screening for mutations, in approximately 40......-60% of childhood developmental disorders the genetic cause remains unknown. Several genome-wide linkage screens in ASD have identified a locus mapping to distal 8q. We have recently identified a novel brain-specific imprinted cluster at this location, which contains the reciprocally expressed maternal KCNK9...... and paternally expressed non-coding PEG13 transcripts, the latter located within an intron of TRAPPC9. Interestingly, mutations of KCNK9 and TRAPPC9 have been reported in Birk-Barel mental retardation and non-syndromic familial forms of ID, respectively. Here, we report a genetic screen for KCNK9 coding...

Clonal mutations in primary human glial tumors: evidence in support of the mutator hypothesis

International Nuclear Information System (INIS)

Misra, Anjan; Chattopadhyay, Parthaprasad; Chosdol, Kunzang; Sarkar, Chitra; Mahapatra, Ashok K; Sinha, Subrata

2007-01-01

A verifiable consequence of the mutator hypothesis is that even low grade neoplasms would accumulate a large number of mutations that do not influence the tumor phenotype (clonal mutations). In this study, we have attempted to quantify the number of clonal mutations in primary human gliomas of astrocytic cell origin. These alterations were identified in tumor tissue, microscopically confirmed to have over 70% neoplastic cells. Random Amplified Polymorphic DNA (RAPD) analysis was performed using a set of fifteen 10-mer primers of arbitrary but definite sequences in 17 WHO grade II astrocytomas (low grade diffuse astrocytoma or DA) and 16 WHO grade IV astrocytomas (Glioblastoma Multiforme or GBM). The RAPD profile of the tumor tissue was compared with that of the leucocyte DNA of the same patient and alteration(s) scored. A quantitative estimate of the overall genomic changes in these tumors was obtained by 2 different modes of calculation. The overall change in the tumors was estimated to be 4.24% in DA and 2.29% in GBM by one method and 11.96% and 6.03% in DA and GBM respectively by the other. The difference between high and lower grade tumors was statistically significant by both methods. This study demonstrates the presence of extensive clonal mutations in gliomas, more in lower grade. This is consistent with our earlier work demonstrating that technique like RAPD analysis, unbiased for locus, is able to demonstrate more intra-tumor genetic heterogeneity in lower grade gliomas compared to higher grade. The results support the mutator hypothesis proposed by Loeb

Role of specific DNA mutations in the peripheral blood of colorectal cancer patients for the assessment of tumor stage and residual disease following tumor resection

Science.gov (United States)

Norcic, Gregor; Jelenc, Franc; Cerkovnik, Petra; Stegel, Vida; Novakovic, Srdjan

2016-01-01

In the present study, the detection of tumor-specific KRAS proto-oncogene, GTPase (KRAS) and B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutations in the peripheral blood of colorectal cancer (CRC) patients at all stages and adenomas was used for the estimation of disease stage prior to surgery and for residual disease following surgery. A total of 65 CRC patients were enrolled. The primary tumor tested positive for the specific mutations (KRAS mutations in codons 12, 13, 61, 117 or 146 and BRAF mutations in codon 600) in 35 patients. In all these patients, the specimen of normal bowel resected with the tumor was also tested for the presence of the same mutations in order to exclude the germ-line mutations. Only patients who tested positive for the specific mutation in the primary tumor were included in further analysis for the presence of tumor-specific mutation in the peripheral blood. No statistically significant differences were found between the detection rates of tumor mutations in the blood and different tumor stages (P=0.491). However, statistically significant differences in the proportions of patients with detected tumor-specific DNA mutations in the peripheral blood were found when comparing the groups of patients with R0 and R2 resections (P=0.038). Tumor-specific DNA mutations in the peripheral blood were more frequently detected in the patients with an incomplete surgical clearance of the tumor due to macroscopic residual disease (R2 resections). Therefore, the study concludes that the follow-up of somatic KRAS- and BRAF-mutated DNA in the peripheral blood of CRC patients may be useful in assessing the surgical clearance of the disease. PMID:27900004

Inference of directional selection and mutation parameters assuming equilibrium.

Science.gov (United States)

Vogl, Claus; Bergman, Juraj

2015-12-01

In a classical study, Wright (1931) proposed a model for the evolution of a biallelic locus under the influence of mutation, directional selection and drift. He derived the equilibrium distribution of the allelic proportion conditional on the scaled mutation rate, the mutation bias and the scaled strength of directional selection. The equilibrium distribution can be used for inference of these parameters with genome-wide datasets of "site frequency spectra" (SFS). Assuming that the scaled mutation rate is low, Wright's model can be approximated by a boundary-mutation model, where mutations are introduced into the population exclusively from sites fixed for the preferred or unpreferred allelic states. With the boundary-mutation model, inference can be partitioned: (i) the shape of the SFS distribution within the polymorphic region is determined by random drift and directional selection, but not by the mutation parameters, such that inference of the selection parameter relies exclusively on the polymorphic sites in the SFS; (ii) the mutation parameters can be inferred from the amount of polymorphic and monomorphic preferred and unpreferred alleles, conditional on the selection parameter. Herein, we derive maximum likelihood estimators for the mutation and selection parameters in equilibrium and apply the method to simulated SFS data as well as empirical data from a Madagascar population of Drosophila simulans. Copyright © 2015 Elsevier Inc. All rights reserved.

Functional analysis of apf1 mutation causing defective amino acid transport in Saccharomyces cerevisiae.

Science.gov (United States)

Horák, J; Kotyk, A

1993-04-01

Mutation in the Apf1 locus causes a pleiotropic effect of H(+)-driven active amino acid transport in baker's yeast Saccharomyces cerevisiae. The uptake of other, presumably H(+)-driven, substances, e.g. of purine and pyrimidine bases, maltose and phosphate ions, is not significantly influenced by this mutation. The apf1 mutation decreases not only the initial rates of amino acid uptake but also the accumulation ratios of amino acids taken up but has virtually no effect on the membrane potential or on the delta pH which constitute the thermodynamically relevant source of energy for their transport. Similarly, no changes in intracellular ATP content, in ATP-hydrolyzing and H(+)-extruding H(+)-ATPase activities, in the efflux of intracellularly accumulated amino acids, or in rates of endogenous respiration, were observed in the apf1 mutant phenotype. Hence, all these data are in accordance with the experiments showing that the Apf1 protein, an integral protein of the endoplasmic reticulum, is required exclusively for efficient processing and translocation of transport proteins specific for amino acids from the endoplasmic reticulum to their final destination, the plasma membrane.

A novel mutation in the nerve-specific 5'UTR of the GJB1 gene causes X-linked Charcot-Marie-Tooth disease.

LENUS (Irish Health Repository)

Murphy, Sinéad M

2011-03-01

X-linked Charcot-Marie-Tooth disease (CMT1X) is the second most common cause of CMT, and is usually caused by mutations in the gap junction protein beta 1 (GJB1) gene which codes for connexin 32 (CX32). CX32 has three tissue-specific promoters, P1 which is specific for liver and pancreas, P1a specific for liver, oocytes and embryonic stem cells, and P2 which is nerve-specific. Over 300 mutations have been described in GJB1, spread throughout the coding region. We describe two families with X-linked inheritance and a phenotype consistent with CMT1X who did not have mutations in the GJB1 coding region. The non-coding region of GJB1 was sequenced and an upstream exon-splicing variant found at approximately - 373G>A which segregated with the disease in both families and was not present in controls. This substitution is located at the last base of the nerve-specific 5\\'UTR and thus may disrupt splicing of the nerve-specific transcript. Online consensus splice-site programs predict a reduced score for the mutant sequence vs. the normal sequence. It is likely that other mutations within the GJB1 non-coding regions account for the CMT1X families who do not have coding region mutations.

One-step isothermal detection of multiple KRAS mutations by forming SNP specific hairpins on a gold nanoshell.

Science.gov (United States)

Chung, Chan Ho; Kim, Joong Hyun

2018-04-24

We developed a one-step isothermal method for typing multiple KRAS mutations using a designed set of primers to form a hairpin on a gold nanoshell upon being ligated by a SNP specific DNA ligase after binding of targets. As a result, we could detect as low as 20 attomoles of KRAS mutations within 1 h.

USP7 Is a Tumor-Specific WNT Activator for APC-Mutated Colorectal Cancer by Mediating β-Catenin Deubiquitination.

Science.gov (United States)

Novellasdemunt, Laura; Foglizzo, Valentina; Cuadrado, Laura; Antas, Pedro; Kucharska, Anna; Encheva, Vesela; Snijders, Ambrosius P; Li, Vivian S W

2017-10-17

The tumor suppressor gene adenomatous polyposis coli (APC) is mutated in most colorectal cancers (CRCs), resulting in constitutive Wnt activation. To understand the Wnt-activating mechanism of the APC mutation, we applied CRISPR/Cas9 technology to engineer various APC-truncated isogenic lines. We find that the β-catenin inhibitory domain (CID) in APC represents the threshold for pathological levels of Wnt activation and tumor transformation. Mechanistically, CID-deleted APC truncation promotes β-catenin deubiquitination through reverse binding of β-TrCP and USP7 to the destruction complex. USP7 depletion in APC-mutated CRC inhibits Wnt activation by restoring β-catenin ubiquitination, drives differentiation, and suppresses xenograft tumor growth. Finally, the Wnt-activating role of USP7 is specific to APC mutations; thus, it can be used as a tumor-specific therapeutic target for most CRCs. Copyright © 2017 The Francis Crick Institute. Published by Elsevier Inc. All rights reserved.

Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer

Science.gov (United States)

Bojesen, Stig E; Pooley, Karen A; Johnatty, Sharon E; Beesley, Jonathan; Michailidou, Kyriaki; Tyrer, Jonathan P; Edwards, Stacey L; Pickett, Hilda A; Shen, Howard C; Smart, Chanel E; Hillman, Kristine M; Mai, Phuong L; Lawrenson, Kate; Stutz, Michael D; Lu, Yi; Karevan, Rod; Woods, Nicholas; Johnston, Rebecca L; French, Juliet D; Chen, Xiaoqing; Weischer, Maren; Nielsen, Sune F; Maranian, Melanie J; Ghoussaini, Maya; Ahmed, Shahana; Baynes, Caroline; Bolla, Manjeet K; Wang, Qin; Dennis, Joe; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Healey, Sue; Lush, Michael; Tessier, Daniel C; Vincent, Daniel; Bacot, Françis; Vergote, Ignace; Lambrechts, Sandrina; Despierre, Evelyn; Risch, Harvey A; González-Neira, Anna; Rossing, Mary Anne; Pita, Guillermo; Doherty, Jennifer A; Álvarez, Nuria; Larson, Melissa C; Fridley, Brooke L; Schoof, Nils; Chang-Claude, Jenny; Cicek, Mine S; Peto, Julian; Kalli, Kimberly R; Broeks, Annegien; Armasu, Sebastian M; Schmidt, Marjanka K; Braaf, Linde M; Winterhoff, Boris; Nevanlinna, Heli; Konecny, Gottfried E; Lambrechts, Diether; Rogmann, Lisa; Guénel, Pascal; Teoman, Attila; Milne, Roger L; Garcia, Joaquin J; Cox, Angela; Shridhar, Vijayalakshmi; Burwinkel, Barbara; Marme, Frederik; Hein, Rebecca; Sawyer, Elinor J; Haiman, Christopher A; Wang-Gohrke, Shan; Andrulis, Irene L; Moysich, Kirsten B; Hopper, John L; Odunsi, Kunle; Lindblom, Annika; Giles, Graham G; Brenner, Hermann; Simard, Jacques; Lurie, Galina; Fasching, Peter A; Carney, Michael E; Radice, Paolo; Wilkens, Lynne R; Swerdlow, Anthony; Goodman, Marc T; Brauch, Hiltrud; García-Closas, Montserrat; Hillemanns, Peter; Winqvist, Robert; Dürst, Matthias; Devilee, Peter; Runnebaum, Ingo; Jakubowska, Anna; Lubinski, Jan; Mannermaa, Arto; Butzow, Ralf; Bogdanova, Natalia V; Dörk, Thilo; Pelttari, Liisa M; Zheng, Wei; Leminen, Arto; Anton-Culver, Hoda; Bunker, Clareann H; Kristensen, Vessela; Ness, Roberta B; Muir, Kenneth; Edwards, Robert; Meindl, Alfons; Heitz, Florian; Matsuo, Keitaro; du Bois, Andreas; Wu, Anna H; Harter, Philipp; Teo, Soo-Hwang; Schwaab, Ira; Shu, Xiao-Ou; Blot, William; Hosono, Satoyo; Kang, Daehee; Nakanishi, Toru; Hartman, Mikael; Yatabe, Yasushi; Hamann, Ute; Karlan, Beth Y; Sangrajrang, Suleeporn; Kjaer, Susanne Krüger; Gaborieau, Valerie; Jensen, Allan; Eccles, Diana; Høgdall, Estrid; Shen, Chen-Yang; Brown, Judith; Woo, Yin Ling; Shah, Mitul; Azmi, Mat Adenan Noor; Luben, Robert; Omar, Siti Zawiah; Czene, Kamila; Vierkant, Robert A; Nordestgaard, Børge G; Flyger, Henrik; Vachon, Celine; Olson, Janet E; Wang, Xianshu; Levine, Douglas A; Rudolph, Anja; Weber, Rachel Palmieri; Flesch-Janys, Dieter; Iversen, Edwin; Nickels, Stefan; Schildkraut, Joellen M; Silva, Isabel Dos Santos; Cramer, Daniel W; Gibson, Lorna; Terry, Kathryn L; Fletcher, Olivia; Vitonis, Allison F; van der Schoot, C Ellen; Poole, Elizabeth M; Hogervorst, Frans B L; Tworoger, Shelley S; Liu, Jianjun; Bandera, Elisa V; Li, Jingmei; Olson, Sara H; Humphreys, Keith; Orlow, Irene; Blomqvist, Carl; Rodriguez-Rodriguez, Lorna; Aittomäki, Kristiina; Salvesen, Helga B; Muranen, Taru A; Wik, Elisabeth; Brouwers, Barbara; Krakstad, Camilla; Wauters, Els; Halle, Mari K; Wildiers, Hans; Kiemeney, Lambertus A; Mulot, Claire; Aben, Katja K; Laurent-Puig, Pierre; van Altena, Anne M; Truong, Thérèse; Massuger, Leon F A G; Benitez, Javier; Pejovic, Tanja; Perez, Jose Ignacio Arias; Hoatlin, Maureen; Zamora, M Pilar; Cook, Linda S; Balasubramanian, Sabapathy P; Kelemen, Linda E; Schneeweiss, Andreas; Le, Nhu D; Sohn, Christof; Brooks-Wilson, Angela; Tomlinson, Ian; Kerin, Michael J; Miller, Nicola; Cybulski, Cezary; Henderson, Brian E; Menkiszak, Janusz; Schumacher, Fredrick; Wentzensen, Nicolas; Marchand, Loic Le; Yang, Hannah P; Mulligan, Anna Marie; Glendon, Gord; Engelholm, Svend Aage; Knight, Julia A; Høgdall, Claus K; Apicella, Carmel; Gore, Martin; Tsimiklis, Helen; Song, Honglin; Southey, Melissa C; Jager, Agnes; van den Ouweland, Ans M W; Brown, Robert; Martens, John W M; Flanagan, James M; Kriege, Mieke; Paul, James; Margolin, Sara; Siddiqui, Nadeem; Severi, Gianluca; Whittemore, Alice S; Baglietto, Laura; McGuire, Valerie; Stegmaier, Christa; Sieh, Weiva; Müller, Heiko; Arndt, Volker; Labrèche, France; Gao, Yu-Tang; Goldberg, Mark S; Yang, Gong; Dumont, Martine; McLaughlin, John R; Hartmann, Arndt; Ekici, Arif B; Beckmann, Matthias W; Phelan, Catherine M; Lux, Michael P; Permuth-Wey, Jenny; Peissel, Bernard; Sellers, Thomas A; Ficarazzi, Filomena; Barile, Monica; Ziogas, Argyrios; Ashworth, Alan; Gentry-Maharaj, Aleksandra; Jones, Michael; Ramus, Susan J; Orr, Nick; Menon, Usha; Pearce, Celeste L; Brüning, Thomas; Pike, Malcolm C; Ko, Yon-Dschun; Lissowska, Jolanta; Figueroa, Jonine; Kupryjanczyk, Jolanta; Chanock, Stephen J; Dansonka-Mieszkowska, Agnieszka; Jukkola-Vuorinen, Arja; Rzepecka, Iwona K; Pylkäs, Katri; Bidzinski, Mariusz; Kauppila, Saila; Hollestelle, Antoinette; Seynaeve, Caroline; Tollenaar, Rob A E M; Durda, Katarzyna; Jaworska, Katarzyna; Hartikainen, Jaana M; Kosma, Veli-Matti; Kataja, Vesa; Antonenkova, Natalia N; Long, Jirong; Shrubsole, Martha; Deming-Halverson, Sandra; Lophatananon, Artitaya; Siriwanarangsan, Pornthep; Stewart-Brown, Sarah; Ditsch, Nina; Lichtner, Peter; Schmutzler, Rita K; Ito, Hidemi; Iwata, Hiroji; Tajima, Kazuo; Tseng, Chiu-Chen; Stram, Daniel O; van den Berg, David; Yip, Cheng Har; Ikram, M Kamran; Teh, Yew-Ching; Cai, Hui; Lu, Wei; Signorello, Lisa B; Cai, Qiuyin; Noh, Dong-Young; Yoo, Keun-Young; Miao, Hui; Iau, Philip Tsau-Choong; Teo, Yik Ying; McKay, James; Shapiro, Charles; Ademuyiwa, Foluso; Fountzilas, George; Hsiung, Chia-Ni; Yu, Jyh-Cherng; Hou, Ming-Feng; Healey, Catherine S; Luccarini, Craig; Peock, Susan; Stoppa-Lyonnet, Dominique; Peterlongo, Paolo; Rebbeck, Timothy R; Piedmonte, Marion; Singer, Christian F; Friedman, Eitan; Thomassen, Mads; Offit, Kenneth; Hansen, Thomas V O; Neuhausen, Susan L; Szabo, Csilla I; Blanco, Ignacio; Garber, Judy; Narod, Steven A; Weitzel, Jeffrey N; Montagna, Marco; Olah, Edith; Godwin, Andrew K; Yannoukakos, Drakoulis; Goldgar, David E; Caldes, Trinidad; Imyanitov, Evgeny N; Tihomirova, Laima; Arun, Banu K; Campbell, Ian; Mensenkamp, Arjen R; van Asperen, Christi J; van Roozendaal, Kees E P; Meijers-Heijboer, Hanne; Collée, J Margriet; Oosterwijk, Jan C; Hooning, Maartje J; Rookus, Matti A; van der Luijt, Rob B; van Os, Theo A M; Evans, D Gareth; Frost, Debra; Fineberg, Elena; Barwell, Julian; Walker, Lisa; Kennedy, M John; Platte, Radka; Davidson, Rosemarie; Ellis, Steve D; Cole, Trevor; Paillerets, Brigitte Bressac-de; Buecher, Bruno; Damiola, Francesca; Faivre, Laurence; Frenay, Marc; Sinilnikova, Olga M; Caron, Olivier; Giraud, Sophie; Mazoyer, Sylvie; Bonadona, Valérie; Caux-Moncoutier, Virginie; Toloczko-Grabarek, Aleksandra; Gronwald, Jacek; Byrski, Tomasz; Spurdle, Amanda B; Bonanni, Bernardo; Zaffaroni, Daniela; Giannini, Giuseppe; Bernard, Loris; Dolcetti, Riccardo; Manoukian, Siranoush; Arnold, Norbert; Engel, Christoph; Deissler, Helmut; Rhiem, Kerstin; Niederacher, Dieter; Plendl, Hansjoerg; Sutter, Christian; Wappenschmidt, Barbara; Borg, Åke; Melin, Beatrice; Rantala, Johanna; Soller, Maria; Nathanson, Katherine L; Domchek, Susan M; Rodriguez, Gustavo C; Salani, Ritu; Kaulich, Daphne Gschwantler; Tea, Muy-Kheng; Paluch, Shani Shimon; Laitman, Yael; Skytte, Anne-Bine; Kruse, Torben A; Jensen, Uffe Birk; Robson, Mark; Gerdes, Anne-Marie; Ejlertsen, Bent; Foretova, Lenka; Savage, Sharon A; Lester, Jenny; Soucy, Penny; Kuchenbaecker, Karoline B; Olswold, Curtis; Cunningham, Julie M; Slager, Susan; Pankratz, Vernon S; Dicks, Ed; Lakhani, Sunil R; Couch, Fergus J; Hall, Per; Monteiro, Alvaro N A; Gayther, Simon A; Pharoah, Paul D P; Reddel, Roger R; Goode, Ellen L; Greene, Mark H; Easton, Douglas F; Berchuck, Andrew; Antoniou, Antonis C; Chenevix-Trench, Georgia; Dunning, Alison M

2013-01-01

TERT-locus single nucleotide polymorphisms (SNPs) and leucocyte telomere measures are reportedly associated with risks of multiple cancers. Using the iCOGs chip, we analysed ~480 TERT-locus SNPs in breast (n=103,991), ovarian (n=39,774) and BRCA1 mutation carrier (11,705) cancer cases and controls. 53,724 participants have leucocyte telomere measures. Most associations cluster into three independent peaks. Peak 1 SNP rs2736108 minor allele associates with longer telomeres (P=5.8×10−7), reduced estrogen receptor negative (ER-negative) (P=1.0×10−8) and BRCA1 mutation carrier (P=1.1×10−5) breast cancer risks, and altered promoter-assay signal. Peak 2 SNP rs7705526 minor allele associates with longer telomeres (P=2.3×10−14), increased low malignant potential ovarian cancer risk (P=1.3×10−15) and increased promoter activity. Peak 3 SNPs rs10069690 and rs2242652 minor alleles increase ER-negative (P=1.2×10−12) and BRCA1 mutation carrier (P=1.6×10−14) breast and invasive ovarian (P=1.3×10−11) cancer risks, but not via altered telomere length. The cancer-risk alleles of rs2242652 and rs10069690 respectively increase silencing and generate a truncated TERT splice-variant. PMID:23535731

Multiple independent variants at the TERT locus are associated with telomere length and risks of breast and ovarian cancer.

Science.gov (United States)

Bojesen, Stig E; Pooley, Karen A; Johnatty, Sharon E; Beesley, Jonathan; Michailidou, Kyriaki; Tyrer, Jonathan P; Edwards, Stacey L; Pickett, Hilda A; Shen, Howard C; Smart, Chanel E; Hillman, Kristine M; Mai, Phuong L; Lawrenson, Kate; Stutz, Michael D; Lu, Yi; Karevan, Rod; Woods, Nicholas; Johnston, Rebecca L; French, Juliet D; Chen, Xiaoqing; Weischer, Maren; Nielsen, Sune F; Maranian, Melanie J; Ghoussaini, Maya; Ahmed, Shahana; Baynes, Caroline; Bolla, Manjeet K; Wang, Qin; Dennis, Joe; McGuffog, Lesley; Barrowdale, Daniel; Lee, Andrew; Healey, Sue; Lush, Michael; Tessier, Daniel C; Vincent, Daniel; Bacot, Françis; Vergote, Ignace; Lambrechts, Sandrina; Despierre, Evelyn; Risch, Harvey A; González-Neira, Anna; Rossing, Mary Anne; Pita, Guillermo; Doherty, Jennifer A; Alvarez, Nuria; Larson, Melissa C; Fridley, Brooke L; Schoof, Nils; Chang-Claude, Jenny; Cicek, Mine S; Peto, Julian; Kalli, Kimberly R; Broeks, Annegien; Armasu, Sebastian M; Schmidt, Marjanka K; Braaf, Linde M; Winterhoff, Boris; Nevanlinna, Heli; Konecny, Gottfried E; Lambrechts, Diether; Rogmann, Lisa; Guénel, Pascal; Teoman, Attila; Milne, Roger L; Garcia, Joaquin J; Cox, Angela; Shridhar, Vijayalakshmi; Burwinkel, Barbara; Marme, Frederik; Hein, Rebecca; Sawyer, Elinor J; Haiman, Christopher A; Wang-Gohrke, Shan; Andrulis, Irene L; Moysich, Kirsten B; Hopper, John L; Odunsi, Kunle; Lindblom, Annika; Giles, Graham G; Brenner, Hermann; Simard, Jacques; Lurie, Galina; Fasching, Peter A; Carney, Michael E; Radice, Paolo; Wilkens, Lynne R; Swerdlow, Anthony; Goodman, Marc T; Brauch, Hiltrud; Garcia-Closas, Montserrat; Hillemanns, Peter; Winqvist, Robert; Dürst, Matthias; Devilee, Peter; Runnebaum, Ingo; Jakubowska, Anna; Lubinski, Jan; Mannermaa, Arto; Butzow, Ralf; Bogdanova, Natalia V; Dörk, Thilo; Pelttari, Liisa M; Zheng, Wei; Leminen, Arto; Anton-Culver, Hoda; Bunker, Clareann H; Kristensen, Vessela; Ness, Roberta B; Muir, Kenneth; Edwards, Robert; Meindl, Alfons; Heitz, Florian; Matsuo, Keitaro; du Bois, Andreas; Wu, Anna H; Harter, Philipp; Teo, Soo-Hwang; Schwaab, Ira; Shu, Xiao-Ou; Blot, William; Hosono, Satoyo; Kang, Daehee; Nakanishi, Toru; Hartman, Mikael; Yatabe, Yasushi; Hamann, Ute; Karlan, Beth Y; Sangrajrang, Suleeporn; Kjaer, Susanne Krüger; Gaborieau, Valerie; Jensen, Allan; Eccles, Diana; Høgdall, Estrid; Shen, Chen-Yang; Brown, Judith; Woo, Yin Ling; Shah, Mitul; Azmi, Mat Adenan Noor; Luben, Robert; Omar, Siti Zawiah; Czene, Kamila; Vierkant, Robert A; Nordestgaard, Børge G; Flyger, Henrik; Vachon, Celine; Olson, Janet E; Wang, Xianshu; Levine, Douglas A; Rudolph, Anja; Weber, Rachel Palmieri; Flesch-Janys, Dieter; Iversen, Edwin; Nickels, Stefan; Schildkraut, Joellen M; Silva, Isabel Dos Santos; Cramer, Daniel W; Gibson, Lorna; Terry, Kathryn L; Fletcher, Olivia; Vitonis, Allison F; van der Schoot, C Ellen; Poole, Elizabeth M; Hogervorst, Frans B L; Tworoger, Shelley S; Liu, Jianjun; Bandera, Elisa V; Li, Jingmei; Olson, Sara H; Humphreys, Keith; Orlow, Irene; Blomqvist, Carl; Rodriguez-Rodriguez, Lorna; Aittomäki, Kristiina; Salvesen, Helga B; Muranen, Taru A; Wik, Elisabeth; Brouwers, Barbara; Krakstad, Camilla; Wauters, Els; Halle, Mari K; Wildiers, Hans; Kiemeney, Lambertus A; Mulot, Claire; Aben, Katja K; Laurent-Puig, Pierre; Altena, Anne Mvan; Truong, Thérèse; Massuger, Leon F A G; Benitez, Javier; Pejovic, Tanja; Perez, Jose Ignacio Arias; Hoatlin, Maureen; Zamora, M Pilar; Cook, Linda S; Balasubramanian, Sabapathy P; Kelemen, Linda E; Schneeweiss, Andreas; Le, Nhu D; Sohn, Christof; Brooks-Wilson, Angela; Tomlinson, Ian; Kerin, Michael J; Miller, Nicola; Cybulski, Cezary; Henderson, Brian E; Menkiszak, Janusz; Schumacher, Fredrick; Wentzensen, Nicolas; Le Marchand, Loic; Yang, Hannah P; Mulligan, Anna Marie; Glendon, Gord; Engelholm, Svend Aage; Knight, Julia A; Høgdall, Claus K; Apicella, Carmel; Gore, Martin; Tsimiklis, Helen; Song, Honglin; Southey, Melissa C; Jager, Agnes; den Ouweland, Ans M Wvan; Brown, Robert; Martens, John W M; Flanagan, James M; Kriege, Mieke; Paul, James; Margolin, Sara; Siddiqui, Nadeem; Severi, Gianluca; Whittemore, Alice S; Baglietto, Laura; McGuire, Valerie; Stegmaier, Christa; Sieh, Weiva; Müller, Heiko; Arndt, Volker; Labrèche, France; Gao, Yu-Tang; Goldberg, Mark S; Yang, Gong; Dumont, Martine; McLaughlin, John R; Hartmann, Arndt; Ekici, Arif B; Beckmann, Matthias W; Phelan, Catherine M; Lux, Michael P; Permuth-Wey, Jenny; Peissel, Bernard; Sellers, Thomas A; Ficarazzi, Filomena; Barile, Monica; Ziogas, Argyrios; Ashworth, Alan; Gentry-Maharaj, Aleksandra; Jones, Michael; Ramus, Susan J; Orr, Nick; Menon, Usha; Pearce, Celeste L; Brüning, Thomas; Pike, Malcolm C; Ko, Yon-Dschun; Lissowska, Jolanta; Figueroa, Jonine; Kupryjanczyk, Jolanta; Chanock, Stephen J; Dansonka-Mieszkowska, Agnieszka; Jukkola-Vuorinen, Arja; Rzepecka, Iwona K; Pylkäs, Katri; Bidzinski, Mariusz; Kauppila, Saila; Hollestelle, Antoinette; Seynaeve, Caroline; Tollenaar, Rob A E M; Durda, Katarzyna; Jaworska, Katarzyna; Hartikainen, Jaana M; Kosma, Veli-Matti; Kataja, Vesa; Antonenkova, Natalia N; Long, Jirong; Shrubsole, Martha; Deming-Halverson, Sandra; Lophatananon, Artitaya; Siriwanarangsan, Pornthep; Stewart-Brown, Sarah; Ditsch, Nina; Lichtner, Peter; Schmutzler, Rita K; Ito, Hidemi; Iwata, Hiroji; Tajima, Kazuo; Tseng, Chiu-Chen; Stram, Daniel O; van den Berg, David; Yip, Cheng Har; Ikram, M Kamran; Teh, Yew-Ching; Cai, Hui; Lu, Wei; Signorello, Lisa B; Cai, Qiuyin; Noh, Dong-Young; Yoo, Keun-Young; Miao, Hui; Iau, Philip Tsau-Choong; Teo, Yik Ying; McKay, James; Shapiro, Charles; Ademuyiwa, Foluso; Fountzilas, George; Hsiung, Chia-Ni; Yu, Jyh-Cherng; Hou, Ming-Feng; Healey, Catherine S; Luccarini, Craig; Peock, Susan; Stoppa-Lyonnet, Dominique; Peterlongo, Paolo; Rebbeck, Timothy R; Piedmonte, Marion; Singer, Christian F; Friedman, Eitan; Thomassen, Mads; Offit, Kenneth; Hansen, Thomas V O; Neuhausen, Susan L; Szabo, Csilla I; Blanco, Ignacio; Garber, Judy; Narod, Steven A; Weitzel, Jeffrey N; Montagna, Marco; Olah, Edith; Godwin, Andrew K; Yannoukakos, Drakoulis; Goldgar, David E; Caldes, Trinidad; Imyanitov, Evgeny N; Tihomirova, Laima; Arun, Banu K; Campbell, Ian; Mensenkamp, Arjen R; van Asperen, Christi J; van Roozendaal, Kees E P; Meijers-Heijboer, Hanne; Collée, J Margriet; Oosterwijk, Jan C; Hooning, Maartje J; Rookus, Matti A; van der Luijt, Rob B; Os, Theo A Mvan; Evans, D Gareth; Frost, Debra; Fineberg, Elena; Barwell, Julian; Walker, Lisa; Kennedy, M John; Platte, Radka; Davidson, Rosemarie; Ellis, Steve D; Cole, Trevor; Bressac-de Paillerets, Brigitte; Buecher, Bruno; Damiola, Francesca; Faivre, Laurence; Frenay, Marc; Sinilnikova, Olga M; Caron, Olivier; Giraud, Sophie; Mazoyer, Sylvie; Bonadona, Valérie; Caux-Moncoutier, Virginie; Toloczko-Grabarek, Aleksandra; Gronwald, Jacek; Byrski, Tomasz; Spurdle, Amanda B; Bonanni, Bernardo; Zaffaroni, Daniela; Giannini, Giuseppe; Bernard, Loris; Dolcetti, Riccardo; Manoukian, Siranoush; Arnold, Norbert; Engel, Christoph; Deissler, Helmut; Rhiem, Kerstin; Niederacher, Dieter; Plendl, Hansjoerg; Sutter, Christian; Wappenschmidt, Barbara; Borg, Ake; Melin, Beatrice; Rantala, Johanna; Soller, Maria; Nathanson, Katherine L; Domchek, Susan M; Rodriguez, Gustavo C; Salani, Ritu; Kaulich, Daphne Gschwantler; Tea, Muy-Kheng; Paluch, Shani Shimon; Laitman, Yael; Skytte, Anne-Bine; Kruse, Torben A; Jensen, Uffe Birk; Robson, Mark; Gerdes, Anne-Marie; Ejlertsen, Bent; Foretova, Lenka; Savage, Sharon A; Lester, Jenny; Soucy, Penny; Kuchenbaecker, Karoline B; Olswold, Curtis; Cunningham, Julie M; Slager, Susan; Pankratz, Vernon S; Dicks, Ed; Lakhani, Sunil R; Couch, Fergus J; Hall, Per; Monteiro, Alvaro N A; Gayther, Simon A; Pharoah, Paul D P; Reddel, Roger R; Goode, Ellen L; Greene, Mark H; Easton, Douglas F; Berchuck, Andrew; Antoniou, Antonis C; Chenevix-Trench, Georgia; Dunning, Alison M

2013-04-01

TERT-locus SNPs and leukocyte telomere measures are reportedly associated with risks of multiple cancers. Using the Illumina custom genotyping array iCOGs, we analyzed ∼480 SNPs at the TERT locus in breast (n = 103,991), ovarian (n = 39,774) and BRCA1 mutation carrier (n = 11,705) cancer cases and controls. Leukocyte telomere measurements were also available for 53,724 participants. Most associations cluster into three independent peaks. The minor allele at the peak 1 SNP rs2736108 associates with longer telomeres (P = 5.8 × 10(-7)), lower risks for estrogen receptor (ER)-negative (P = 1.0 × 10(-8)) and BRCA1 mutation carrier (P = 1.1 × 10(-5)) breast cancers and altered promoter assay signal. The minor allele at the peak 2 SNP rs7705526 associates with longer telomeres (P = 2.3 × 10(-14)), higher risk of low-malignant-potential ovarian cancer (P = 1.3 × 10(-15)) and greater promoter activity. The minor alleles at the peak 3 SNPs rs10069690 and rs2242652 increase ER-negative (P = 1.2 × 10(-12)) and BRCA1 mutation carrier (P = 1.6 × 10(-14)) breast and invasive ovarian (P = 1.3 × 10(-11)) cancer risks but not via altered telomere length. The cancer risk alleles of rs2242652 and rs10069690, respectively, increase silencing and generate a truncated TERT splice variant.

The distribution of and complementation relationships between spontaneous X-linked recessive lethal mutations recovered from crossing long-term laboratory stocks of Drosophila melanogaster

International Nuclear Information System (INIS)

Schalet, A.P.

1986-01-01

Drosophila melanogaster males from a wild-type laboratory stock, were mated with virgin females of the M-6 stock, and 149 spontaneous independent non-mosaically transmitted, as well as 8 incidentally detected, mosaically transmitted, X-linked recessive lethal mutations were recovered from 95 704 F 2 cultures. 152 mutations were mapped over the entire length of the X-chromosome by complementation and/or crossover tests. Although there were far too few spontaneous mutations to make a meaningful comparison of relative mutability on a locus-by-locus basis, those loci displaying a relatively higher X-ray mutability, when taken as a group, tend to display a relatively higher spontaneous mutability, and those loci displaying a relatively lower X-ray mutability, when taken as a group, tend to display a relatively lower spontaneous mutability. (Auth.)

Bulldog dwarfism in Dexter cattle is caused by mutations in ACAN.

Science.gov (United States)

Cavanagh, Julie A L; Tammen, Imke; Windsor, Peter A; Bateman, John F; Savarirayan, Ravi; Nicholas, Frank W; Raadsma, Herman W

2007-11-01

Bulldog dwarfism in Dexter cattle is one of the earliest single-locus disorders described in animals. Affected fetuses display extreme disproportionate dwarfism, reflecting abnormal cartilage development (chondrodysplasia). Typically, they die around the seventh month of gestation, precipitating a natural abortion. Heterozygotes show a milder form of dwarfism, most noticeably having shorter legs. Homozygosity mapping in candidate regions in a small Dexter pedigree suggested aggrecan (ACAN) as the most likely candidate gene. Mutation screening revealed a 4-bp insertion in exon 11 (2266_2267insGGCA) (called BD1 for diagnostic testing) and a second, rarer transition in exon 1 (-198C>T) (called BD2) that cosegregate with the disorder. In chondrocytes from cattle heterozygous for the insertion, mutant mRNA is subject to nonsense-mediated decay, showing only 8% of normal expression. Genotyping in Dexter families throughout the world shows a one-to-one correspondence between genotype and phenotype at this locus. The heterozygous and homozygous-affected Dexter cattle could prove invaluable as a model for human disorders caused by mutations in ACAN.

Novel compound heterozygous mutations in MYO7A in a Chinese family with Usher syndrome type 1.

Science.gov (United States)

Liu, Fei; Li, Pengcheng; Liu, Ying; Li, Weirong; Wong, Fulton; Du, Rong; Wang, Lei; Li, Chang; Jiang, Fagang; Tang, Zhaohui; Liu, Mugen

2013-01-01

To identify the disease-causing mutation(s) in a Chinese family with autosomal recessive Usher syndrome type 1 (USH1). An ophthalmic examination and an audiometric test were conducted to ascertain the phenotype of two affected siblings. The microsatellite marker D11S937, which is close to the candidate gene MYO7A (USH1B locus), was selected for genotyping. From the DNA of the proband, all coding exons and exon-intron boundaries of MYO7A were sequenced to identify the disease-causing mutation(s). Restriction fragment length polymorphism (RFLP) analysis was performed to exclude the alternative conclusion that the mutations are non-pathogenic rare polymorphisms. Based on severe hearing impairment, unintelligible speech, and retinitis pigmentosa, a clinical diagnosis of Usher syndrome type 1 was made. The genotyping results did not exclude the USH1B locus, which suggested that the MYO7A gene was likely the gene associated with the disease-causing mutation(s) in the family. With direct DNA sequencing of MYO7A, two novel compound heterozygous mutations (c.3742G>A and c.6051+1G>A) of MYO7A were identified in the proband. DNA sequence analysis and RFLP analysis of other family members showed that the mutations cosegregated with the disease. Unaffected members, including the parents, uncle, and sister of the proband, carry only one of the two mutations. The mutations were not present in the controls (100 normal Chinese subjects=200 chromosomes) according to the RFLP analysis. In this study, we identified two novel mutations, c.3742G>A (p.E1248K) and c.6051+1G>A (donor splice site mutation in intron 44), of MYO7A in a Chinese non-consanguineous family with USH1. The mutations cosegregated with the disease and most likely cause the phenotype in the two affected siblings who carry these mutations compound heterozygously. Our finding expands the mutational spectrum of MYO7A.

Heterozygous Mutations in TREX1 Cause Familial Chilblain Lupus and Dominant Aicardi-Goutières Syndrome

Science.gov (United States)

Rice, Gillian; Newman, William G.; Dean, John; Patrick, Teresa; Parmar, Rekha; Flintoff, Kim; Robins, Peter; Harvey, Scott; Hollis, Thomas; O’Hara, Ann; Herrick, Ariane L.; Bowden, Andrew P.; Perrino, Fred W.; Lindahl, Tomas; Barnes, Deborah E.; Crow, Yanick J.

2007-01-01

TREX1 constitutes the major 3′→5′ DNA exonuclease activity measured in mammalian cells. Recently, biallelic mutations in TREX1 have been shown to cause Aicardi-Goutières syndrome at the AGS1 locus. Interestingly, Aicardi-Goutières syndrome shows overlap with systemic lupus erythematosus at both clinical and pathological levels. Here, we report a heterozygous TREX1 mutation causing familial chilblain lupus. Additionally, we describe a de novo heterozygous mutation, affecting a critical catalytic residue in TREX1, that results in typical Aicardi-Goutières syndrome. PMID:17357087

A monoclonal antibody IMab-1 specifically recognizes IDH1{sup R132H}, the most common glioma-derived mutation

Energy Technology Data Exchange (ETDEWEB)

Kato, Yukinari, E-mail: yukinari-k@bea.hi-ho.ne.jp [Department of Pathology, Duke University Medical Center, DUMC-3156, Durham, NC 27710 (United States); The Oncology Research Center, Research Institute for Advanced Molecular Epidemiology, Yamagata University, 2-2-2 Iida-nishi, Yamagata 990-9585 (Japan); Jin, Genglin; Kuan, Chien-Tsun; McLendon, Roger E.; Yan, Hai; Bigner, Darell D. [Department of Pathology, Duke University Medical Center, DUMC-3156, Durham, NC 27710 (United States)

2009-12-18

IDH1 (isocitrate dehydrogenase 1) mutations have been identified as early and frequent genetic alterations in astrocytomas, oligodendrogliomas, and oligoastrocytomas as well as secondary glioblastomas. In contrast, primary glioblastomas very rarely contain IDH1 mutations, although primary and secondary glioblastomas are histologically indistinguishable. The IDH1 mutations are remarkably specific to a single codon in the conserved and functionally important Arg132 in IDH1. In gliomas, the most frequent IDH1 mutations (>90%) were G395A (R132H). In this study, we immunized mice with R132H-containing IDH1 (IDH1{sup R132H}) peptide. After cell fusion using Sendai virus envelope, the monoclonal antibodies (mAbs), which specifically reacted with IDH1{sup R132H}, were screened in ELISA. One of the mAbs, IMab-1 reacted with the IDH1{sup R132H} peptide, but not with wild type IDH1 (IDH1{sup wt}) peptide in ELISA. In Western-blot analysis, IMab-1 reacted with only the IDH1{sup R132H} protein, not IDH1{sup wt} protein or the other IDH1 mutants, indicating that IMab-1 is IDH1{sup R132H}-specific. Furthermore, IMab-1 specifically stained the IDH1{sup R132H}-expressing cells in astrocytomas in immunohistochemistry, whereas it did not react with IDH1{sup R132H}-negative primary glioblastoma sections. In conclusion, we established an anti-IDH1{sup R132H}-specific monoclonal antibody IMab-1, which should be significantly useful for diagnosis and biological evaluation of mutation-bearing gliomas.

Specific and straightforward molecular investigation of β-thalassemia mutations in the Malaysian Malays and Chinese using direct TaqMan genotyping assays.

Science.gov (United States)

Kho, S L; Chua, K H; George, E; Tan, J A M A

2013-07-15

Beta-thalassemia is a life-threatening inherited blood disorder. Rapid characterization of β-globin gene mutations is necessary because of the high frequency of Malaysian β-thalassemia carriers. A combination real-time polymerase chain reaction genotyping assay using TaqMan probes was developed to confirm β-globin gene mutations. In this study, primers and probes were designed to specifically identify 8 common β-thalassemia mutations in the Malaysian Malay and Chinese ethnic groups using the Primer Express software. "Blind tests" using DNA samples from healthy individuals and β-thalassemia patients with different genotypes were performed to determine the specificity and sensitivity of this newly designed assay. Our results showed 100% sensitivity and specificity for this novel assay. In conclusion, the TaqMan genotyping assay is a straightforward assay that allows detection of β-globin gene mutations in less than 40 min. The simplicity and reproducibility of the TaqMan genotyping assay permit its use in laboratories as a rapid and cost-effective diagnostic tool for confirmation of common β-thalassemia mutations in Malaysia.

Fixation effect of SurePath preservative fluids using epidermal growth factor receptor mutation-specific antibodies for immunocytochemistry.

Science.gov (United States)

Kawahara, Akihiko; Taira, Tomoki; Abe, Hideyuki; Watari, Kosuke; Murakami, Yuichi; Fukumitsu, Chihiro; Takase, Yorihiko; Yamaguchi, Tomohiko; Azuma, Koichi; Akiba, Jun; Ono, Mayumi; Kage, Masayoshi

2014-02-01

Cytological diagnosis of respiratory disease has become important, not only for histological typing using immunocytochemistry (ICC) but also for molecular DNA analysis of cytological material. The aim of this study was to investigate the fixation effect of SurePath preservative fluids. Human lung cancer PC9 and 11-18 cell lines, and lung adenocarcinoma cells in pleural effusion, were fixed in CytoRich Blue, CytoRich Red, 15% neutral-buffered formalin, and 95% ethanol, respectively. PC9 and 11-18 cell lines were examined by ICC with epidermal growth factor receptor (EGFR) mutation-specific antibodies, the EGFR mutation DNA assay, and fluorescence in situ hybridization. The effect of antigenic storage time was investigated in lung adenocarcinoma cells in pleural effusion by ICC using the lung cancer detection markers. PC9 and 11-18 cell lines in formalin-based fixatives showed strong staining of EGFR mutation-specific antibodies and lung cancer detection markers by ICC as compared with ethanol-based fixatives. DNA preservation with CytoRich Blue and CytoRich Red was superior to that achieved with 95% ethanol and 15% neutral-buffered formalin fixatives, whereas EGFR mutations by DNA assay and EGFR gene amplification by fluorescence in situ hybridization were successfully identified in all fixative samples. Although cytoplasmic antigens maintained high expression levels, expression levels in nuclear antigens fell as storage time increased. These results indicate that CytoRich Red is not only suitable for ICC with EGFR mutation-specific antibodies, but also for DNA analysis of cytological material, and is useful in molecular testing of lung cancer, for which various types of analyses will be needed in future. © 2013 American Cancer Society.

EsrE-A yigP Locus-Encoded Transcript-Is a 3′ UTR sRNA Involved in the Respiratory Chain of E. coli

Directory of Open Access Journals (Sweden)

Hui Xia

2017-08-01

Full Text Available The yigP locus is widely conserved among γ-proteobacteria. Mutation of the yigP locus impacts aerobic growth of Gram-negative bacteria. However, the underlying mechanism of how the yigP locus influences aerobic growth remains largely unknown. Here, we demonstrated that the yigP locus in Escherichia coli encodes two transcripts; the mRNA of ubiquinone biosynthesis protein, UbiJ, and the 3′ untranslated region small regulatory RNA (sRNA, EsrE. EsrE is an independent transcript that is transcribed using an internal promoter of the yigP locus. Surprisingly, we found that both the EsrE sRNA and UbiJ protein were required for Q8 biosynthesis, and were sufficient to rescue the growth defect ascribed to deletion of the yigP locus. Moreover, our data showed that EsrE targeted multiple mRNAs involved in several cellular processes including murein biosynthesis and the tricarboxylic acid cycle. Among these targets, sdhD mRNA that encodes one subunit of succinate dehydrogenase (SDH, was significantly activated. Our findings provided an insight into the important function of EsrE in bacterial adaptation to various environments, as well as coordinating different aspects of bacterial physiology.

Concomitant BCORL1 and BRAF Mutations in Vemurafenib-Resistant Melanoma Cells.

Science.gov (United States)

Mologni, Luca; Costanza, Mariantonia; Sharma, Geeta Geeta; Viltadi, Michela; Massimino, Luca; Citterio, Stefania; Purgante, Stefania; Raman, Hima; Pirola, Alessandra; Zucchetti, Massimo; Piazza, Rocco; Gambacorti-Passerini, Carlo

2018-05-01

BRAF is the most frequently mutated gene in melanoma. Constitutive activation of mutant BRAF V600E leads to aberrant Ras-independent MAPK signaling and cell transformation. Inhibition of mutant BRAF is a current frontline therapy for such cases, with improved survival compared with chemotherapy. Unfortunately, reactivation of MAPK signaling by several mechanisms has been shown to cause drug resistance and disease recurrence. In this work, we describe the co-occurrence of an in-frame deletion within an amplified BRAF V600E locus and a missense point mutation of the transcriptional repressor BCORL1 in vemurafenib-resistant A375 melanoma cells. Functional data confirmed that truncated p47BRAF V600E and mutant BCORL1 Q1076H both contribute to resistance. Interestingly, either endogenous BCORL1 silencing or ectopic BCORL1 Q1076H expression mimicked the effects of a CRISPR/Cas9-edited BCORL1 Q1076H locus, suggesting a complex mixture of loss- and gain-of-function effects caused by the mutation. Transcriptomic data confirmed this hypothesis. Finally, we show that the pan-RAF inhibitor sorafenib is not affected by expression of BRAF deletion variant and effectively synergizes with vemurafenib to block resistant cells, suggesting a possible intervention for this class of mutants. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

The L locus, one of complementary genes required for anthocyanin production in onions (Allium cepa), encodes anthocyanidin synthase.

Science.gov (United States)

Kim, Sunggil; Jones, Rick; Yoo, Kil-Sun; Pike, Leonard M

2005-06-01

Bulb color in onions (Allium cepa) is an important trait, but its complex, unclear mechanism of inheritance has been a limiting factor in onion cultivar improvement. The identity of the L locus, which is involved in the color difference between Brazilian yellow and red onions, is revealed in this study. A cross was made between a US-type yellow breeding line and a Brazilian yellow cultivar. The segregation ratio of nine red to seven yellow onions in the F(2) population supports the involvement of two complementary genes in anthocyanin production in the F(1) hybrids. The high-performance liquid chromatography (HPLC) and reverse-transcriptase (RT)-PCR analysis of the Brazilian yellow onions indicated that the genes are involved late in the anthocyanin synthesis pathway. The genomic sequence of the anthocyanidin synthase (ANS) gene in Brazilian yellow onions showed a point mutation, which results in an amino acid change of a glycine to an arginine at residue 229. Because this residue is located adjacent to a highly conserved iron-binding active site, this mutation is likely responsible for the inactivation of the ANS gene in Brazilian yellow onions. Following the isolation of the promoter sequence of the mutant allele, a PCR-based marker for allelic selection of the ANS gene was designed. This assay is based on an insertion (larger than 3 kb) mutation. The marker perfectly co-segregated with the color phenotypes in the F(2) populations, thereby indicating that the L locus encodes ANS.

Locus de Controle e escolha do método anticoncepcional Locus de Control y método anticonceptivo elegido Locus of Control and choice of contraceptive method

Directory of Open Access Journals (Sweden)

Aline Salheb Alves

2007-06-01

Full Text Available Objetivou-se avaliar a relação entre o Locus de Controle e o tipo de método contraceptivo escolhido. Foi utilizada a Escala Multidimensional de Locus de Controle de Levenson e entrevistadas 191 mulheres. As usuárias de preservativo masculino apresentaram maior Internalidade do que as usuárias de injetável mensal. Quanto ao locus Externalidade Outros Poderosos, as usuárias de implante apresentavam menor externalidade do que as usuárias de preservativo masculino, laqueadura, injetável trimestral e DIU. Considerando-se o locus Externalidade Acaso, as usuárias de implante apresentaram menores escores do que as mulheres que optaram pela laqueadura, injetável trimestral e DIU. Observou-se ainda, menor Externalidade Acaso entre as usuárias de injetável mensal em relação às mulheres que fizeram opção pelo injetável trimestral.El objetivo es validar la relación entre el Locus de Control y el tipo de método anticonceptivo elegido. Fue usada la Escala Multidimensional de Locus de Control de Levenson. Fueron entrevistadas 191 mujeres. Las usuarias de condón masculino presentaron Internalidad más grande que las usuarias de inyectable mensual. Considerado el Locus Externalidad - Otro poderoso, las usuarias de implante presentaron menor externalidad de que las usuarias de condón masculino, laqueadura, inyectable trimestral y DIU. Considerado el Locus Externalidad - Quizá, las usuarias del implante presentaron menores resultados que las mujeres que eligieron por la laqueadura, inyectable trimestral y DIU. Se observo que las mujeres usuarias de inyectable mensual presentaron menor Externalidad - Quizá que las mujeres usuarias de inyectable trimestral.The purpose was to assess the relationship between locus of control and the contraceptive method chosen. It was used the Levenson's Multidimensional Locus of Control Scale and 191 women was interviewed. Users of male condoms presented greater Internality than the monthly contraceptive

Clonal mutations in primary human glial tumors: evidence in support of the mutator hypothesis

Directory of Open Access Journals (Sweden)

Sarkar Chitra

2007-10-01

Full Text Available Abstract Background A verifiable consequence of the mutator hypothesis is that even low grade neoplasms would accumulate a large number of mutations that do not influence the tumor phenotype (clonal mutations. In this study, we have attempted to quantify the number of clonal mutations in primary human gliomas of astrocytic cell origin. These alterations were identified in tumor tissue, microscopically confirmed to have over 70% neoplastic cells. Methods Random Amplified Polymorphic DNA (RAPD analysis was performed using a set of fifteen 10-mer primers of arbitrary but definite sequences in 17 WHO grade II astrocytomas (low grade diffuse astrocytoma or DA and 16 WHO grade IV astrocytomas (Glioblastoma Multiforme or GBM. The RAPD profile of the tumor tissue was compared with that of the leucocyte DNA of the same patient and alteration(s scored. A quantitative estimate of the overall genomic changes in these tumors was obtained by 2 different modes of calculation. Results The overall change in the tumors was estimated to be 4.24% in DA and 2.29% in GBM by one method and 11.96% and 6.03% in DA and GBM respectively by the other. The difference between high and lower grade tumors was statistically significant by both methods. Conclusion This study demonstrates the presence of extensive clonal mutations in gliomas, more in lower grade. This is consistent with our earlier work demonstrating that technique like RAPD analysis, unbiased for locus, is able to demonstrate more intra-tumor genetic heterogeneity in lower grade gliomas compared to higher grade. The results support the mutator hypothesis proposed by Loeb.

Common mutations in the fibroblast growth factor receptor 3 (FGFR 3) gene account for achondroplasia, hypochondroplasia, and thanatophoric dwarfism

Energy Technology Data Exchange (ETDEWEB)

Bonaventure, J.; Rousseau, F.; Legeai-Mallet, L.; LeMerrer, M.; Munnich, A.; Maroteaux, P. [INSERM, Paris (France)

1996-05-03

The mapping of the achondroplasia locus to the short arm of chromosome 4 and the subsequent identification of a recurrent missense mutation (G380R) in the fibroblast growth factor receptor 3 (FGFR-3) gene has been followed by the detection of common FGFR-3 mutations in two clinically related disorders: thanatophoric dwarfism (types I and II) and hypochondroplasia. The relative clinical homogeneity of achondroplasia was substantiated by demonstration of its genetic homogeneity as more than 98% of all patients hitherto reported exhibit mutations in the transmembrane receptor domain. Although most hypochondroplasia cases were accounted for by a recurrent missense substitution (N540K) in the first tyrosine kinase (TK 1) domain of the receptor, a significant proportion (40%) of our patients did not harbor the N540K mutation and three hypochondroplasia families were not linked to the FGFR-3 locus, thus supporting clinical heterogeneity of this condition. In thanatophoric dwarfism (TD), a recurrent FGFR-3 mutation located in the second tyrosine kinase (TK 2) domain of the receptor was originally detected in 100% of TD II cases; in our series, seven distinct mutations in three different protein domains were identified in 25 of 26 TD I patients, suggesting that TD, like achondroplasia, is a genetically homogenous skeletal disorder. 31 refs., 4 figs., 2 tabs.

A TAD boundary is preserved upon deletion of the CTCF-rich Firre locus.

Science.gov (United States)

Barutcu, A Rasim; Maass, Philipp G; Lewandowski, Jordan P; Weiner, Catherine L; Rinn, John L

2018-04-13

The binding of the transcriptional regulator CTCF to the genome has been implicated in the formation of topologically associated domains (TADs). However, the general mechanisms of folding the genome into TADs are not fully understood. Here we test the effects of deleting a CTCF-rich locus on TAD boundary formation. Using genome-wide chromosome conformation capture (Hi-C), we focus on one TAD boundary on chromosome X harboring ~ 15 CTCF binding sites and located at the long non-coding RNA (lncRNA) locus Firre. Specifically, this TAD boundary is invariant across evolution, tissues, and temporal dynamics of X-chromosome inactivation. We demonstrate that neither the deletion of this locus nor the ectopic insertion of Firre cDNA or its ectopic expression are sufficient to alter TADs in a sex-specific or allele-specific manner. In contrast, Firre's deletion disrupts the chromatin super-loop formation of the inactive X-chromosome. Collectively, our findings suggest that apart from CTCF binding, additional mechanisms may play roles in establishing TAD boundary formation.

Photoreactivation of conversion and de novo suppressor mutation in Escherichia coli

Energy Technology Data Exchange (ETDEWEB)

Bockrath, R C; Plamer, J E [Indiana Univ., Indianapolis (USA). Dept. of Microbiology

1977-04-01

Studies of mutagenesis and photoreactivation in various E.coli strains have shown that conversion mutation of a mutant containing an amber suppressor to one containing an ochre suppressor is sensitive to photoreactivation. Direct photoreactivation by photoreactivating light (PRL) after uv mutagenesis reduced mutation frequencies by a factor of about 2 for each minute of exposure during the first 5 to 8 min of exposure for cells with normal repair capacity. Conversion and potential de novo suppressor mutations were about equally sensitive. For conversion, the sensitivities to PRL were identical in the repair-normal and excisions-repair-deficient strains. For de novo suppressor mutation, the rate of mutation frequency reduction by PRL in the repair-deficient strain was about one-half that in the other strains. The results suggest that ultraviolet radiation produces both de novo suppressor mutation and conversion at the sup(E,B) locus by photoreversible pyrimidine dimers in the DNA. The causative dimers could be Thy()Cyt dimers in the transcribed strand or the non-transcribed strand, respectively.

Sex-specific incidence of EGFR mutation and its association with age and obesity in lung adenocarcinomas: a retrospective analysis.

Science.gov (United States)

Kim, Hye-Ryoun; Kim, Seo Yun; Kim, Cheol Hyeon; Yang, Sung Hyun; Lee, Jae Cheol; Choi, Chang-Min; Na, Im Il

2017-11-01

Age and obesity are well-known risk factors for various cancers, but the potential roles of age and obesity in lung cancer, especially in those with activating EGFR mutations, have not been thoroughly evaluated. The aim of this retrospective study is to evaluate the associations between the sex-specific incidence of EGFR mutations and age and obesity. We conducted a retrospective study based on the data from 1378 lung adenocarcinoma cases. The degree of obesity was categorized by body mass index (BMI). The associations between EGFR mutational status and clinical factors, including stage, smoking history, age group (≤45 years, 46-55, 56-65 and >65), and BMI group (obesity (adjusted OR for BMI group = 1.23, p-trend = 0.04). In contrast, in women, the incidence of EGFR mutation was positively associated with age (adjusted OR for age group = 1.19, p-trend = 0.02). However, the incidence of EGFR mutation was not statistically associated with obesity (adjusted OR for BMI group = 1.03, p-trend = 0.76). Our data suggests that age and obesity may contribute to the sex-specific incidence of EGFR mutation in lung adenocarcinoma in different manners.

A deep intronic CLRN1 (USH3A) founder mutation generates an aberrant exon and underlies severe Usher syndrome on the Arabian Peninsula.

Science.gov (United States)

Khan, Arif O; Becirovic, Elvir; Betz, Christian; Neuhaus, Christine; Altmüller, Janine; Maria Riedmayr, Lisa; Motameny, Susanne; Nürnberg, Gudrun; Nürnberg, Peter; Bolz, Hanno J

2017-05-03

Deafblindness is mostly due to Usher syndrome caused by recessive mutations in the known genes. Mutation-negative patients therefore either have distinct diseases, mutations in yet unknown Usher genes or in extra-exonic parts of the known genes - to date a largely unexplored possibility. In a consanguineous Saudi family segregating Usher syndrome type 1 (USH1), NGS of genes for Usher syndrome, deafness and retinal dystrophy and subsequent whole-exome sequencing each failed to identify a mutation. Genome-wide linkage analysis revealed two small candidate regions on chromosome 3, one containing the USH3A gene CLRN1, which has never been associated with Usher syndrome in Saudi Arabia. Whole-genome sequencing (WGS) identified a homozygous deep intronic mutation, c.254-649T > G, predicted to generate a novel donor splice site. CLRN1 minigene-based analysis confirmed the splicing of an aberrant exon due to usage of this novel motif, resulting in a frameshift and a premature termination codon. We identified this mutation in an additional two of seven unrelated mutation-negative Saudi USH1 patients. Locus-specific markers indicated that c.254-649T > G CLRN1 represents a founder allele that may significantly contribute to deafblindness in this population. Our finding underlines the potential of WGS to uncover atypically localized, hidden mutations in patients who lack exonic mutations in the known disease genes.

Physical mapping of the major early-onset familial Alzheimer`s disease locus on chromosome 14 and analysis of candidate gene sequences

Energy Technology Data Exchange (ETDEWEB)

Tanzi, R.E.; Romano, D.M.; Crowley, A.C. [Harvard Medical School, Charlestown, MA (United States)] [and others

1994-09-01

Genetic studies of kindreds displaying evidence for familial AD (FAD) have led to the localization of gene defects responsible for this disorder on chromosomes 14, 19, and 21. A minor early-onset FAD gene on chromosome 21 has been identified to enode the amyloid precursor protein (APP), and the late-onset FAD susceptibility locus on chromosome 19 has been shown to be in linkage disequilibrium with the E4 allele of the APOE gene. Meanwhile, the locus responsible for the major form of early-onset FAD on chromosome 14q24 has not yet been identified. By recombinational analysis, we have refined the minimal candidate region containing the gene defect to approximately 3 megabases in 14q24. We will describe our laboratory`s progress on attempts to finely localize this locus, as well as test known candidate genes from this region for either inclusion in the minimal candidate region or the presence of pathogenic mutations. Candidate genes that have been tested so far include cFOS, heat shock protein 70 member (HSF2A), transforming growth factor beta (TGFB3), the trifunctional protein C1-THF synthase (MTHFD), bradykinin receptor (BR), and the E2k component of a-ketoglutarate dehydrogenase. HSP2A, E2k, MTHFD, and BR do not map to the current defined minimal candidate region; however, sequence analysis must be performed to confirm exclusion of these genes as true candidates. Meanwhile, no pathogenic mutations have yet been found in cFOS or TGFB3. We have also isolated a large number of novel transcribed sequences from the minimal candidate region in the form of {open_quotes}trapped exons{close_quotes} from cosmids identified by hybridization to select YAC clones; we are currently in the process of searching for pathogenic mutations in these exons in affected individuals from FAD families.

Familial isolated primary pigmented nodular adrenocortical disease associated with a novel low penetrance PRKAR1A gene splice site mutation

DEFF Research Database (Denmark)

Storr, Helen L; Metherell, Louise A; Dias, Renuka

2010-01-01

Primary pigmented nodular adrenocortical disease (PPNAD) is associated with inactivating germline protein kinase A regulatory subunit type 1-alpha (PRKAR1A) mutations and loss of heterozygosity at the 17q22-24 locus in approximately 50% patients. PRKAR1A mutations are observed in both isolated PP...... PPNAD (iPPNAD) and Carney complex (CNC). Most mutations result in a functionally null-allele and exhibit high penetrance. We genotyped members of an extended family for a novel PRKAR1A mutation and undertook detailed phenotyping for CNC in the affected individuals....

Genome-wide association study identifies a novel canine glaucoma locus.

Directory of Open Access Journals (Sweden)

Saija J Ahonen

Full Text Available Glaucoma is an optic neuropathy and one of the leading causes of blindness. Its hereditary forms are classified into primary closed-angle (PCAG, primary open-angle (POAG and primary congenital glaucoma (PCG. Although many loci have been mapped in human, only a few genes have been identified that are associated with the development of glaucoma and the genetic basis of the disease remains poorly understood. Glaucoma has also been described in many dog breeds, including Dandie Dinmont Terriers (DDT in which it is a late-onset (>7 years disease. We designed clinical and genetic studies to better define the clinical features of glaucoma in the DDT and to identify the genetic cause. Clinical diagnosis was based on ophthalmic examinations of the affected dogs and 18 additionally investigated unaffected DDTs. We collected DNA from over 400 DTTs and a genome wide association study was performed in a cohort of 23 affected and 23 controls, followed by a fine mapping, a replication study and candidate gene sequencing. The clinical study suggested that ocular abnormalities including abnormal iridocorneal angles and pectinate ligament dysplasia are common (50% and 72%, respectively in the breed and the disease resembles human PCAG. The genetic study identified a novel 9.5 Mb locus on canine chromosome 8 including the 1.6 Mb best associated region (p = 1.63 × 10(-10, OR = 32 for homozygosity. Mutation screening in five candidate genes did not reveal any causative variants. This study indicates that although ocular abnormalities are common in DDTs, the genetic risk for glaucoma is conferred by a novel locus on CFA8. The canine locus shares synteny to a region in human chromosome 14q, which harbors several loci associated with POAG and PCG. Our study reveals a new locus for canine glaucoma and ongoing molecular studies will likely help to understand the genetic etiology of the disease.

Self-incompatibility in Petunia inflata: the relationship between a self-incompatibility locus F-box protein and its non-self S-RNases.

Science.gov (United States)

Sun, Penglin; Kao, Teh-hui

2013-02-01

The highly polymorphic S (for self-incompatibility) locus regulates self-incompatibility in Petunia inflata; the S-RNase regulates pistil specificity, and multiple S-locus F-box (SLF) genes regulate pollen specificity. The collaborative non-self recognition model predicts that, for any S-haplotype, an unknown number of SLFs collectively recognize all non-self S-RNases to mediate their ubiquitination and degradation. Using a gain-of-function assay, we examined the relationships between S2-SLF1 (for S2-allelic product of Type-1 SLF) and four S-RNases. The results suggest that S2-SLF1 interacts with S7- and S13-RNases, and the previously identified S1- and S3-RNases, but not with S5- or S11-RNase. An artificial microRNA expressed by the S2-SLF1 promoter, but not by the vegetative cell-specific promoter, Late Anther Tomato 52, suppressed expression of S2-SLF1 in S2 pollen, suggesting that SLF1 is specific to the generative cell. The S2 pollen with S2-SLF1 suppressed was compatible with S3-, S5-, S7-, S11-, and S13-carrying pistils, confirming that other SLF proteins are responsible for detoxifying S5- and S11-RNases and suggesting that S2-SLF1 is not the only SLF in S2 pollen that interacts with S3-, S7-, and S13-RNases. Petunia may have evolved at least two types of SLF proteins to detoxify any non-self S-RNase to minimize the deleterious effects of mutation in any SLF.

Comprehensive mutational screening in a cohort of Danish families with hereditary congenital cataract

DEFF Research Database (Denmark)

Hansen, Lars; Mikkelsen, Annemette; Nürnberg, Peter

2009-01-01

, and a gene conversion is the most likely mutational event causing this variant. Ten families had microcornea cataract, and a mutation was identified in eight of those. Most families displayed mixed phenotypes with nuclear, lamellar, and polar opacities and no apparent genotype-phenotype correlation emerged......PURPOSE: Identification of the causal mutations in 28 unrelated families and individuals with hereditary congenital cataract identified from a national Danish register of hereditary eye diseases. Seven families have been published previously, and the data of the remaining 21 families are presented...... together with an overview of the results in all families. METHODS: A combined screening approach of linkage analysis and sequencing of 17 cataract genes were applied to mutation analyses of total 28 families. RESULTS: The study revealed a disease locus in seven of eight families that were amenable...

HEALTH LOCUS OF CONTROL PERCEPTION OF ADOLESCENTS, AND ITS EFFECTS ON THEIR HEALTH BEHAVIOURS

Directory of Open Access Journals (Sweden)

Ruhi Selcuk TABAK

2006-04-01

Full Text Available Main objective of this study is to investigate the relationships between health locus of control perceptions and health behaviours of adolescents as well as the effectiveness of lectures on health locus of control to them. The subjects of our study are 192 students in 6 groups of the 9. Grade students of a high school. Three groups of 108 students were randomly selected as the experiment group who were subjected to 4 class-hours specific lectures on health locus of control. The rest 84 students constituted the control group. A 34-item questionnaire for health behaviours and the Multidimensional Health Locus of Control Scale (MHLOC, were filled by the students before and after the lectures. The lectures on health locus of control increased the perception of internal health locus of control of adolescents while decreasing chance health locus of control. The differences between experiment and control groups in this aspect were found to be statistically significant. Internal health locus of control is the main source for the increase of responsibility and management of individuals on their health. The relations that were detected between students’ health behaviours and information solicitation and their perceptions of health locus of control showed that the students with higher internal health locus of control are more eager to be responsible and active for their health, especially, for the health behaviours such as physical exercise, smoking, tooth-brushing, medical check-ups so on. [TAF Prev Med Bull 2006; 5(2.000: 118-130

Prevalence of 2314delG mutation in Spanish patients with Usher syndrome type II (USH2).

Science.gov (United States)

Beneyto, M M; Cuevas, J M; Millán, J M; Espinós, C; Mateu, E; González-Cabo, P; Baiget, M; Doménech, M; Bernal, S; Ayuso, C; García-Sandoval, B; Trujillo, M J; Borrego, S; Antiñolo, G; Carballo, M; Nájera, C

2000-06-01

The Usher syndrome (USH) is a group of autosomal recessive diseases characterized by congenital sensorineural hearing loss and retinitis pigmentosa. Three clinically distinct forms of Usher syndrome have so far been recognized and can be distinguished from one another by assessing auditory and vestibular function. Usher syndrome type II (USH2) patients have congenital moderate-to-severe nonprogressive hearing loss, retinitis pigmentosa, and normal vestibular function. Genetic linkage studies have revealed genetic heterogeneity among the three types of USH, with the majority of USH2 families showing linkage to the USH2A locus in 1q41. The USH2A gene (MIM 276901) has been identified: three mutations, 2314delG, 2913delG, and 4353-54delC, were initially reported in USH2A patients, the most frequent of which is the 2314delG mutation. It has been reported that this mutation can give rise to typical and atypical USH2 phenotypes. USH2 cases represent 62% of all USH cases in the Spanish population, and 95% of these cases have provided evidence of linkage to the USH2A locus. In the present study, the three reported mutations were analyzed in 59 Spanish families with a diagnosis of USH type II. The 2314delG was the only mutation identified in our population: it was detected in 25% of families and 16% of USH2 chromosomes analyzed. This study attempts to estimate the prevalence of this common mutation in a homogeneous Spanish population.

Whole-genome resequencing reveals candidate mutations for pig prolificacy.

Science.gov (United States)

Li, Wen-Ting; Zhang, Meng-Meng; Li, Qi-Gang; Tang, Hui; Zhang, Li-Fan; Wang, Ke-Jun; Zhu, Mu-Zhen; Lu, Yun-Feng; Bao, Hai-Gang; Zhang, Yuan-Ming; Li, Qiu-Yan; Wu, Ke-Liang; Wu, Chang-Xin

2017-12-20

Changes in pig fertility have occurred as a result of domestication, but are not understood at the level of genetic variation. To identify variations potentially responsible for prolificacy, we sequenced the genomes of the highly prolific Taihu pig breed and four control breeds. Genes involved in embryogenesis and morphogenesis were targeted in the Taihu pig, consistent with the morphological differences observed between the Taihu pig and others during pregnancy. Additionally, excessive functional non-coding mutations have been specifically fixed or nearly fixed in the Taihu pig. We focused attention on an oestrogen response element (ERE) within the first intron of the bone morphogenetic protein receptor type-1B gene ( BMPR1B ) that overlaps with a known quantitative trait locus (QTL) for pig fecundity. Using 242 pigs from 30 different breeds, we confirmed that the genotype of the ERE was nearly fixed in the Taihu pig. ERE function was assessed by luciferase assays, examination of histological sections, chromatin immunoprecipitation, quantitative polymerase chain reactions, and western blots. The results suggest that the ERE may control pig prolificacy via the cis-regulation of BMPR1B expression. This study provides new insight into changes in reproductive performance and highlights the role of non-coding mutations in generating phenotypic diversity between breeds. © 2017 The Author(s).

Haplotype structure in Ashkenazi Jewish BRCA1 and BRCA2 mutation carriers

DEFF Research Database (Denmark)

Im, Kate M; Kirchhoff, Tomas; Wang, Xianshu

2011-01-01

Three founder mutations in BRCA1 and BRCA2 contribute to the risk of hereditary breast and ovarian cancer in Ashkenazi Jews (AJ). They are observed at increased frequency in the AJ compared to other BRCA mutations in Caucasian non-Jews (CNJ). Several authors have proposed that elevated allele...... the tools of statistical genomics to examine the likelihood of long-range LD at a deleterious locus in a population that faced a genetic bottleneck. We studied the genotypes of hundreds of women from a large international consortium of BRCA1 and BRCA2 mutation carriers and found that AJ women exhibited long......-range haplotypes compared to CNJ women. More than 50% of the AJ chromosomes with the BRCA1 185delAG mutation share an identical 2.1 Mb haplotype and nearly 16% of AJ chromosomes carrying the BRCA2 6174delT mutation share a 1.4 Mb haplotype. Simulations based on the best inference of Ashkenazi population demography...

Active site mutations change the cleavage specificity of neprilysin.

Directory of Open Access Journals (Sweden)

Travis Sexton

Full Text Available Neprilysin (NEP, a member of the M13 subgroup of the zinc-dependent endopeptidase family is a membrane bound peptidase capable of cleaving a variety of physiological peptides. We have generated a series of neprilysin variants containing mutations at either one of two active site residues, Phe(563 and Ser(546. Among the mutants studied in detail we observed changes in their activity towards leucine(5-enkephalin, insulin B chain, and amyloid β(1-40. For example, NEP(F563I displayed an increase in preference towards cleaving leucine(5-enkephalin relative to insulin B chain, while mutant NEP(S546E was less discriminating than neprilysin. Mutants NEP(F563L and NEP(S546E exhibit different cleavage site preferences than neprilysin with insulin B chain and amyloid ß(1-40 as substrates. These data indicate that it is possible to alter the cleavage site specificity of neprilysin opening the way for the development of substrate specific or substrate exclusive forms of the enzyme with enhanced therapeutic potential.

Genetic analysis of suppressors of the PF10 mutation in Chlamydomonas reinhardtii

International Nuclear Information System (INIS)

Dutcher, S.K.; Gibbons, W.; Inwood, W.B.

1988-01-01

A mutation at the PF10 locus of the unicellular green alga Chlamydomonas reinhardtii leads to abnormal cell motility. The asymmetric form of the ciliary beat stroke characteristic of wild-type flagella is modified by this mutation to a nearly symmetric beat. We report here that this abnormal motility is a conditional phenotype that depends on light intensity. In the absence of light or under low light intensities, the motility is more severely impaired than at higher light intensities. By UV mutagenesis we obtained 11 intragenic and 70 extragenic strains that show reversion of the pf10 motility phenotype observed in low light. The intragenic events reverted the motility phenotype of the pf10 mutation completely. The extragenic events define at least seven suppressor loci; these map to linkage groups IV, VII, IX, XI, XII and XVII. Suppressor mutations at two of the seven loci (LIS1 and LIS2) require light for their suppressor activity. Forty-eight of the 70 extragenic suppressors were examined in heterozygous diploid cells; 47 of these mutants were recessive to the wild-type allele and one mutant (bop5-1) was dominant to the wild-type allele. Complementation analysis of the 47 recessive mutants showed unusual patterns. Most mutants within a recombinationally defined group failed to complement one another, although there were pairs that showed intra-allelic complementation. Additionally, some of the mutants at each recombinationally defined locus failed to complement mutants at other loci. They define dominant enhancers of one another

Clonal expansion to anaplasia in Wilms` tumors is associated with p53 mutations

Energy Technology Data Exchange (ETDEWEB)

Pelletier, J.; Beckwith, B.; Bardeesy, N. [Loma Linda Univ., CA (United States)]|[McGill Univ., Montreal (Canada)

1994-09-01

The genetics of Wilms` tumor (WT), a pediatric malignancy of the kidney, is complex. Three loci are implicated in WT initiation and include the WT1 tumor suppressor gene (residing at 11p13), an 11p15 locus, and a non-11p locus. As well, allelic loss at 16q24 in {approximately}20% of sporadic WTs suggests the location of (an) additional gene(s) involved in tumor progression. Initiation and progression in WTs is associated with multiple histological variants. Anaplasia is a rare WT subtype associated with poor prognosis and defined by enlarged and multipolar mitotic figures, a threefold nuclear enlargement (compared with adjacent nuclei of the same cell type), and hyperchromasia of the enlarged nuclei. We have previously demonstrated that p53 gene mutations are exclusively associated with anaplastic WTs, being absent from a large number of non-anaplastic WTs analyzed. To determine if such mutations are involved in clonal progression to anaplasia, we performed a retrospective analysis of histologically defined sections from tumor specimens. Six of ten WTs demonstrated p53 mutations by PCR-single stranded conformational polymorphism analysis. Two of these samples were paired, consisting of geographically demarcated anaplastic cells embedded within a non-anaplastic tumor bed. In these cases, p53 mutations were only present in the anaplastic region of the tumor. An overall decrease in the number of apoptotic cells was found associated with the anaplastic tumor region, compared to adjacent non-anaplastic tumor bed. These results indicate that p53 mutations arise during progression to anaplasia late in Wilms` tumor etiology and are associated with a more aggressive form of this cancer.

Relationships between Locus of Control, Self-Efficacy, Efforts and Academic Achievement among Engineering Students

Directory of Open Access Journals (Sweden)

Alias Maizam

2016-01-01

Full Text Available The aim of this study is to investigate the relationships between the affective learning needs namely, self-efficacy and locus of control, learning efforts and academic achievement among engineering students. For this purpose, a survey was conducted on first year engineering students from two technical universities in Malaysia. Self-efficacy and locus of control were assessed using existing instruments while learning efforts were assessed using a specifically designed instrument based on Carbonaro’s model of learning effort. Academic achievement data were based on cumulative grade point average (CGPA obtained from self-report by participants. The findings indicate that females engineering students tend to have higher self-efficacy compared to males while both groups have similar locus of control and invest in similar learning efforts. Only locus of control is found to be related to academic achievement while self-efficacy is found to be related to efforts. In conclusion, locus of control seems to be an important factor in predicting academic achievement among engineering students.

A strabismus susceptibility locus on chromosome 7p

Science.gov (United States)

Parikh, Vaishali; Shugart, Yin Yao; Doheny, Kimberly F.; Zhang, Jie; Li, Lan; Williams, John; Hayden, David; Craig, Brian; Capo, Hilda; Chamblee, Denise; Chen, Cathy; Collins, Mary; Dankner, Stuart; Fiergang, Dean; Guyton, David; Hunter, David; Hutcheon, Marcia; Keys, Marshall; Morrison, Nancy; Munoz, Michelle; Parks, Marshall; Plotsky, David; Protzko, Eugene; Repka, Michael X.; Sarubbi, Maria; Schnall, Bruce; Siatkowski, R. Michael; Traboulsi, Elias; Waeltermann, Joanne; Nathans, Jeremy

2003-01-01

Strabismus has been known to have a significant genetic component, but the mode of inheritance and the identity of the relevant genes have been enigmatic. This paper reports linkage analysis of nonsyndromic strabismus. The principal results of this study are: (i) the demonstrated feasibility of identifying and recruiting large families in which multiple members have (or had) strabismus; (ii) the linkage in one large family of a presumptive strabismus susceptibility locus to 7p22.1 with a multipoint logarithm of odds score of 4.51 under a model of recessive inheritance; and (iii) the failure to observe significant linkage to 7p in six other multiplex families, consistent with genetic heterogeneity among families. These findings suggest that it will be possible to localize and ultimately identify strabismus susceptibility genes by linkage analysis and mutation screening of candidate genes. PMID:14519848

PCR-based methods for the detection of L1014 kdr mutation in Anopheles culicifacies sensu lato

Science.gov (United States)

Singh, Om P; Bali, Prerna; Hemingway, Janet; Subbarao, Sarala K; Dash, Aditya P; Adak, Tridibes

2009-01-01

Background Anopheles culicifacies s.l., a major malaria vector in India, has developed widespread resistance to DDT and is becoming resistant to pyrethroids–the only insecticide class recommended for the impregnation of bed nets. Knock-down resistance due to a point mutation in the voltage gated sodium channel at L1014 residue (kdr) is a common mechanism of resistance to DDT and pyrethroids. The selection of this resistance may pose a serious threat to the success of the pyrethroid-impregnated bed net programme. This study reports the presence of kdr mutation (L1014F) in a field population of An. culicifacies s.l. and three new PCR-based methods for kdr genotyping. Methods The IIS4-IIS5 linker to IIS6 segments of the para type voltage gated sodium channel gene of DDT and pyrethroid resistant An. culicifacies s.l. population from the Surat district of India was sequenced. This revealed the presence of an A-to-T substitution at position 1014 leading to a leucine-phenylalanine mutation (L1014F) in a few individuals. Three molecular methods viz. Allele Specific PCR (AS-PCR), an Amplification Refractory Mutation System (ARMS) and Primer Introduced Restriction Analysis-PCR (PIRA-PCR) were developed and tested for kdr genotyping. The specificity of the three assays was validated following DNA sequencing of the samples genotyped. Results The genotyping of this An. culicifacies s.l. population by the three PCR based assays provided consistent result and were in agreement with DNA sequencing result. A low frequency of the kdr allele mostly in heterozygous condition was observed in the resistant population. Frequencies of the different genotypes were in Hardy-Weinberg equilibrium. Conclusion The Leu-Phe mutation, which generates the kdr phenotype in many insects, was detected in a pyrethroid and DDT resistant An. culicifacies s.l. population. Three PCR-based methods were developed for kdr genotyping. All the three assays were specific. The ARMS method was refractory to non-specific

PCR-based methods for the detection of L1014 kdr mutation in Anopheles culicifacies sensu lato

Directory of Open Access Journals (Sweden)

Dash Aditya P

2009-07-01

was refractory to non-specific amplification in non-stringent amplification conditions. The PIRA-PCR assay is able to detect both the codons for the phenylalanine mutation at kdr locus, i.e., TTT and TTC, in a single assay, although the latter codon was not found in the population genotyped.

Crosstalk between histone modifications maintains the developmental pattern of gene expression on a tissue-specific locus.

Science.gov (United States)

Hosey, Alison M; Chaturvedi, Chandra-Prakash; Brand, Marjorie

2010-05-16

Genome wide studies have provided a wealth of information related to histone modifications. Particular modifications, which can encompass both broad and discrete regions, are associated with certain genomic elements and gene expression status. Here we focus on how studies on the beta-globin gene cluster can complement the genome wide effort through the thorough dissection of histone modifying protein crosstalk. The beta-globin locus serves as a model system to study both regulation of gene expression driven at a distance by enhancers and mechanisms of developmental switching of clustered genes. We investigate recent studies, which uncover that histone methyltransferases, recruited at the beta-globin enhancer, control gene expression by long range propagation on chromatin. Specifically, we focus on how seemingly antagonistic complexes, such as those including MLL2, G9a and UTX, can cooperate to functionally regulate developmentally controlled gene expression. Finally, we speculate on the mechanisms of chromatin modifying complex propagation on genomic domains.

Functional characterization of a CRH missense mutation identified in an ADNFLE family.

Directory of Open Access Journals (Sweden)

Veronica Sansoni

Full Text Available Nocturnal frontal lobe epilepsy has been historically considered a channelopathy caused by mutations in subunits of the neuronal nicotinic acetylcholine receptor or in a recently reported potassium channel. However, these mutations account for only a minority of patients, and the existence of at least a new locus for the disease has been demonstrated. In 2005, we detected two nucleotide variations in the promoter of the CRH gene coding for the corticotropin releasing hormone in 7 patients. These variations cosegregated with the disease and were demonstrated to alter the cellular levels of this hormone. Here, we report the identification in an Italian affected family of a novel missense mutation (hpreproCRH p.Pro30Arg located in the region of the CRH coding for the protein pro-sequence. The mutation was detected in heterozygosity in the two affected individuals. In vitro assays demonstrated that this mutation results in reduced levels of protein secretion in the short time thus suggesting that mutated people could present an altered capability to respond immediately to stress agents.

X-ray-induced bystander response reduce spontaneous mutations in V79 cells

International Nuclear Information System (INIS)

Maeda, Munetoshi; Kobayashi, Katsumi; Matsumoto, Hideki; Usami, Noriko; Tomiya, Masanori

2013-01-01

The potential for carcinogenic risks is increased by radiation-induced bystander responses; these responses are the biological effects in unirradiated cells that receive signals from the neighboring irradiated cells. Bystander responses have attracted attention in modern radiobiology because they are characterized by non-linear responses to low-dose radiation. We used a synchrotron X-ray microbeam irradiation system developed at the Photon Factory, High Energy Accelerator Research Organization, KEK, and showed that nitric oxide (NO)-mediated bystander cell death increased biphasically in a dose-dependent manner. Here, we irradiated five cell nuclei using 10 × 10 µm 2 5.35 keV X-ray beams and then measured the mutation frequency at the hypoxanthine-guanosine phosphoribosyl transferase (HPRT) locus in bystander cells. The mutation frequency with the null radiation dose was 2.6 × 10 -5 (background level), and the frequency decreased to 5.3 × 10 -6 with a dose of approximately 1 Gy (absorbed dose in the nucleus of irradiated cells). At high doses, the mutation frequency returned to the background level. A similar biphasic dose-response effect was observed for bystander cell death. Furthermore, we found that incubation with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), a specific scavenger of NO, suppressed not only the biphasic increase in bystander cell death but also the biphasic reduction in mutation frequency of bystander cells. These results indicate that the increase in bystander cell death involves mechanisms that suppress mutagenesis. This study has thus shown that radiation-induced bystander responses could affect processes that protect the cell against naturally occurring alterations such as mutations. (author)

Gene mutation-based and specific therapies in precision medicine.

Science.gov (United States)

Wang, Xiangdong

2016-04-01

Precision medicine has been initiated and gains more and more attention from preclinical and clinical scientists. A number of key elements or critical parts in precision medicine have been described and emphasized to establish a systems understanding of precision medicine. The principle of precision medicine is to treat patients on the basis of genetic alterations after gene mutations are identified, although questions and challenges still remain before clinical application. Therapeutic strategies of precision medicine should be considered according to gene mutation, after biological and functional mechanisms of mutated gene expression or epigenetics, or the correspondent protein, are clearly validated. It is time to explore and develop a strategy to target and correct mutated genes by direct elimination, restoration, correction or repair of mutated sequences/genes. Nevertheless, there are still numerous challenges to integrating widespread genomic testing into individual cancer therapies and into decision making for one or another treatment. There are wide-ranging and complex issues to be solved before precision medicine becomes clinical reality. Thus, the precision medicine can be considered as an extension and part of clinical and translational medicine, a new alternative of clinical therapies and strategies, and have an important impact on disease cures and patient prognoses. © 2015 The Author. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

DNA modification study of major depressive disorder: beyond locus-by-locus comparisons.

Science.gov (United States)

Oh, Gabriel; Wang, Sun-Chong; Pal, Mrinal; Chen, Zheng Fei; Khare, Tarang; Tochigi, Mamoru; Ng, Catherine; Yang, Yeqing A; Kwan, Andrew; Kaminsky, Zachary A; Mill, Jonathan; Gunasinghe, Cerisse; Tackett, Jennifer L; Gottesman, Irving I; Willemsen, Gonneke; de Geus, Eco J C; Vink, Jacqueline M; Slagboom, P Eline; Wray, Naomi R; Heath, Andrew C; Montgomery, Grant W; Turecki, Gustavo; Martin, Nicholas G; Boomsma, Dorret I; McGuffin, Peter; Kustra, Rafal; Petronis, Art

2015-02-01

Major depressive disorder (MDD) exhibits numerous clinical and molecular features that are consistent with putative epigenetic misregulation. Despite growing interest in epigenetic studies of psychiatric diseases, the methodologies guiding such studies have not been well defined. We performed DNA modification analysis in white blood cells from monozygotic twins discordant for MDD, in brain prefrontal cortex, and germline (sperm) samples from affected individuals and control subjects (total N = 304) using 8.1K CpG island microarrays and fine mapping. In addition to the traditional locus-by-locus comparisons, we explored the potential of new analytical approaches in epigenomic studies. In the microarray experiment, we detected a number of nominally significant DNA modification differences in MDD and validated selected targets using bisulfite pyrosequencing. Some MDD epigenetic changes, however, overlapped across brain, blood, and sperm more often than expected by chance. We also demonstrated that stratification for disease severity and age may increase the statistical power of epimutation detection. Finally, a series of new analytical approaches, such as DNA modification networks and machine-learning algorithms using binary and quantitative depression phenotypes, provided additional insights on the epigenetic contributions to MDD. Mapping epigenetic differences in MDD (and other psychiatric diseases) is a complex task. However, combining traditional and innovative analytical strategies may lead to identification of disease-specific etiopathogenic epimutations. Copyright © 2015 Society of Biological Psychiatry. All rights reserved.

Genetic linkage analyses and Cx50 mutation detection in a large multiplex Chinese family with hereditary nuclear cataract.

Science.gov (United States)

He, Wei; Li, Xin; Chen, Jiajing; Xu, Ling; Zhang, Feng; Dai, Qiushi; Cui, Hao; Wang, Duen-Mei; Yu, Jun; Hu, Songnian; Lu, Shan

2011-03-01

The aim of the study was to characterize the underlying mutation in a large multiplex Chinese family with hereditary nuclear cataract. A 6-generation Chinese family having hereditary nuclear cataract was recruited and clinically verified. Blood DNA samples were obtained from 53 available family members. Linkage analyses were performed on the known candidate regions for hereditary cataract with 36 polymorphic microsatellite markers. To identify mutations related to cataract, a direct sequencing approach was applied to a candidate gene residing in our linkage locus. A linkage locus was identified with a maximum 2-point LOD score of 4.31 (recombination fraction = 0) at marker D1S498 and a maximum multipoint LOD score of 5.7 between markers D1S2344 and D1S498 on chromosome 1q21.1, where the candidate gene Cx50 is located. Direct sequencing of Cx50 showed a 139 G to A transition occurred in all affected family members. This transitional mutation resulted in a replacement of aspartic acid by asparagine at residue 47 (D47N) and led to a loss-of-function of the protein. The D47N mutation of Cx50 causes the hereditary nuclear cataract in this family in an autosomal dominant mode of inheritance with incomplete penetrance.

Hypomutability in Fanconi anemia cells is associated with increased deletion frequency at the HPRT locus

International Nuclear Information System (INIS)

Papadopoulo, D.; Guillouf, C.; Moustacchi, E.; Mohrenweiser, H.

1990-01-01

Fanconi anemia (FA) is an inherited human disorder associated with a predisposition to cancer and characterized by anomalies in the processing of DNA cross-links and certain monoadducts. The authors reported previously that the frequency of psoralen-photoinduced mutations at the HPRT locus is lower in FA cells than in normal cells. This hypomutability is shown here to be associated with an increased frequency of deletions in the HPRT gene when either a mixture of cross-links and monoadducts or monoadducts alone are induced. Molecular analysis of mutants in the HPRT gene was carried out. In normal cells the majority of spontaneous and induced mutants are point mutations whereas in FA deletion mutations predominate. In that case a majority of mutants were found to lack individual exons or small clusters of exons whereas in normal cells large (complete or major gene loss) and small deletions are almost equally represented. Thus they propose that the FA defect lies in a mutagenic pathway that, in normal cells, involves by passing lesions and subsequent gap filling by a recombinational process during replication

Stepwise Exposure of Staphylococcus aureus to Pleuromutilins Is Associated with Stepwise Acquisition of Mutations in rplC and Minimally Affects Susceptibility to Retapamulin▿

Science.gov (United States)

Gentry, Daniel R.; Rittenhouse, Stephen F.; McCloskey, Lynn; Holmes, David J.

2007-01-01

To assess their effects on susceptibility to retapamulin in Staphylococcus aureus, first-, second-, and third-step mutants with elevated MICs to tiamulin and other investigational pleuromutilin compounds were isolated and characterized through exposure to high drug concentrations. All first- and second-step mutations were in rplC, encoding ribosomal protein L3. Most third-step mutants acquired a third mutation in rplC. While first- and second-step mutations did cause an elevation in tiamulin and retapamulin MICs, a significant decrease in activity was not seen until a third mutation was acquired. All third-step mutants exhibited severe growth defects, and faster-growing variants arose at a high frequency from most isolates. These faster-growing variants were found to be more susceptible to pleuromutilins. In the case of a mutant with three alterations in rplC, the fast-growing variants acquired an additional mutation in rplC. In the case of fast-growing variants of isolates with two mutations in rplC and at least one mutation at an unmapped locus, one of the two rplC mutations reverted to wild type. These data indicate that mutations in rplC that lead to pleuromutilin resistance have a direct, negative effect on fitness. While reduction in activity of retapamulin against S. aureus can be seen through mutations in rplC, it is likely that target-specific resistance to retapamulin will be slow to emerge due to the need for three mutations for a significant effect on activity and the fitness cost of each mutational step. PMID:17404009

[Mutants of the yeast Saccharomyces cerevisiae characterized by enhanced induced mutagenesis. III. Effect of the him mutation on the effectiveness and specificity of UF-induced mutagenesis].

Science.gov (United States)

Ivanov, E L; Koval'tsova, S V; Korolev, V G

1987-09-01

We have studied the influence of him1-1, him2-1, him3-1 and himX mutations on induction frequency and specificity of UV-induced adenine-dependent mutations in the yeast Saccharomyces cerevisiae. Him mutations do not render haploid cells more sensitive to the lethal action of UV-light; however, in him strains adenine-dependent mutations (ade1, ade2) were induced more frequently (1.5--2-fold), as compared to the HIM strain. An analysis of the molecular nature of ade2 mutants revealed that him1-1, him2-1 and himX mutations increase specifically the yield of transitions (AT----GC and GC----AT), whereas in the him3-1 strain the yield of transversions was enhanced as well. We suggest him mutations analysed to affect specific repair pathway for mismatch correction.

Genetic counseling in Usher syndrome: linkage and mutational analysis of 10 Colombian families.

Science.gov (United States)

Tamayo, M L; Lopez, G; Gelvez, N; Medina, D; Kimberling, W J; Rodríguez, V; Tamayo, G E; Bernal, J E

2008-01-01

Usher Syndrome (US), an autosomal recessive disease, is characterized by retinitis pigmentosa (RP), vestibular dysfunction, and congenital sensorineural deafness. There are three recognized clinical types of the disorder. In order to improve genetic counseling for affected families, we conducted linkage analysis and DNA sequencing in 10 Colombian families with confirmed diagnosis of US (4 type I and 6 type II). Seventy-five percent of the US1 families showed linkage to locus USH1B, while the remaining 25% showed linkage to loci USH1B and USH1C. Among families showing linkage to USH1B we found two different mutations in the MYO7A gene: IVS42-26insTTGAG in exon 43 (heterozygous state) and R634X (CGA-TGA) in exon 16 (homozygous state). All six US2 families showed linkage to locus USH2A. Of them, 4 had c.2299delG mutation (1 homozygote state and 3 heterozygous); in the remaining 2 we did not identify any pathologic DNA variant. USH2A individuals with a 2299delG mutation presented a typical and homogeneous retinal phenotype with bilateral severe hearing loss, except for one individual with a heterozygous 2299delG mutation, whose hearing loss was asymmetric, but more profound than in the other cases. The study of these families adds to the genotype-phenotype characterization of the different types and subtypes of US and facilitates genetic counseling in these families. We would like to emphasize the need to perform DNA studies as a prerequisite for genetic counseling in affected families.

Preimplantation genetic diagnosis of Von Hippel-Lindau disease cancer syndrome by combined mutation and segregation analysis

Directory of Open Access Journals (Sweden)

Denilce R. Sumita

2007-03-01

Full Text Available Von Hippel-Lindau (VHL disease is an autosomal dominant cancer syndrome, associated with the development of tumors and cysts in multiple organ systems, whose expression and age of onset are highly variable. The VHL disease tumor suppressor gene (VHL maps to 3p25-p26 and mutations ranging from a single base change to large deletions have been detected in patients with VHL disease. We developed a single cell PCR protocol for preimplantation genetic diagnosis (PGD of VHL disease to select unaffected embryos on the basis of the detection of the specific mutation and segregation analysis of polymorphic linked markers. Multiplex-nested PCR using single buccal cells of an affected individual were performed in order to test the accuracy and reliability of this single-cell protocol. For each locus tested, amplification efficiency was 83% to 87% and allelic drop-out rates ranged from 12% to 8%. Three VHL disease PGD cycles were performed on cells from a couple with paternal transmission of a 436delC mutation in exon 2 of the VHL gene, leading to the identification of three unaffected embryos. Independent of the mutation present, this general PGD protocol for the diagnosis of VHL disease can be used in families informative for either the D3S1038 or D3S1317 microsatellite markers.

Oscillating Evolution of a Mammalian Locus with Overlapping Reading Frames: An XLalphas/ALEX Relay.

Directory of Open Access Journals (Sweden)

2005-08-01

Full Text Available XLalphas and ALEX are structurally unrelated mammalian proteins translated from alternative overlapping reading frames of a single transcript. Not only are they encoded by the same locus, but a specific XLalphas/ALEX interaction is essential for G-protein signaling in neuroendocrine cells. A disruption of this interaction leads to abnormal human phenotypes, including mental retardation and growth deficiency. The region of overlap between the two reading frames evolves at a remarkable speed: the divergence between human and mouse ALEX polypeptides makes them virtually unalignable. To trace the evolution of this puzzling locus, we sequenced it in apes, Old World monkeys, and a New World monkey. We show that the overlap between the two reading frames and the physical interaction between the two proteins force the locus to evolve in an unprecedented way. Namely, to maintain two overlapping protein-coding regions the locus is forced to have high GC content, which significantly elevates its intrinsic evolutionary rate. However, the two encoded proteins cannot afford to change too quickly relative to each other as this may impair their interaction and lead to severe physiological consequences. As a result XLalphas and ALEX evolve in an oscillating fashion constantly balancing the rates of amino acid replacements. This is the first example of a rapidly evolving locus encoding interacting proteins via overlapping reading frames, with a possible link to the origin of species-specific neurological differences.

PMS2 mutations in childhood cancer.

Science.gov (United States)

De Vos, Michel; Hayward, Bruce E; Charlton, Ruth; Taylor, Graham R; Glaser, Adam W; Picton, Susan; Cole, Trevor R; Maher, Eamonn R; McKeown, Carole M E; Mann, Jill R; Yates, John R; Baralle, Diana; Rankin, Julia; Bonthron, David T; Sheridan, Eamonn

2006-03-01

Until recently, the PMS2 DNA mismatch repair gene has only rarely been implicated as a cancer susceptibility locus. New studies have shown, however, that earlier analyses of this gene have had technical limitations and also that the genetic behavior of mutant PMS2 alleles is unusual, in that, unlike MLH1 or MSH2 mutations, PMS2 mutations show low heterozygote penetrance. As a result, a dominantly inherited cancer predisposition has not been a feature reported in families with PMS2 mutations. Such families have instead been ascertained through childhood-onset cancers in homozygotes or through apparently sporadic colorectal cancer in heterozygotes. We present further information on the phenotype associated with homozygous PMS2 deficiency in 13 patients from six families of Pakistani origin living in the United Kingdom. This syndrome is characterized by café-au-lait skin pigmentation and a characteristic tumor spectrum, including leukemias, lymphomas, cerebral malignancies (such as supratentorial primitive neuroectodermal tumors, astrocytomas, and glioblastomas), and colorectal neoplasia with an onset in early adult life. We present evidence for a founder effect in five families, all of which carried the same R802-->X mutation (i.e., arginine-802 to stop) in PMS2. This cancer syndrome can be mistaken for neurofibromatosis type 1, with important management implications including the risk of the disorder occurring in siblings and the likelihood of tumor development in affected individuals.

Biodosimetry of Chernobyl cleanup workers from Estonia and Latvia using the glycophorin A in vivo somatic cell mutation assay

International Nuclear Information System (INIS)

Bigbee, W.L.; Jensen, R.H.; Veidebaum, T.

1997-01-01

The reactor accident at Chernobyl in 1986 necessitated a massive environmental cleanup that involved over 600,000 workers from all 15 Republics of the former Soviet Union. To determine whether the whole-body radiation received by workers in the course of these decontamination activities resulted in a detectable biological response, over 1,500 blood samples were obtained from cleanup workers sent from two Baltic countries, Estonia and Latvia. Here we report the results of studies of biodosimetry using the glycophorin A (GPA) locus in vivo somatic cell mutation assay applied to 734 blood samples from these workers, to 51 control samples from unexposed Baltic populations and to 94 samples from historical U.S. controls. The data reveal inconsistent evidence that the protracted radiation exposures received by these workers resulted in a significant dose-associated increase in GPA locus mutations compared with the controls. Taken together, these data suggest that the average radiation exposure to these workers does not greatly exceed 10 cGy, the minimum levels at which radiation effects might be detectable by the assay. Although the protracted nature of the exposure may have reduced the efficiency of induction of GPA locus mutations, it is likely that the estimated physical doses for these cleanup worker populations (median reported dose 9.5 cGy) were too low to result in radiation damage to erythroid stem cells that can be detected reliably by this method. 25 refs., 2 figs., 3 tabs

Genetic heterogeneity in familial exudative vitreoretinopathy; exclusion of the EVR1 locus on chromosome 11q in a large autosomal dominant pedigree.

Science.gov (United States)

Bamashmus, M A; Downey, L M; Inglehearn, C F; Gupta, S R; Mansfield, D C

2000-04-01

Familial exudative vitreoretinopathy (FEVR) is associated with mutations in the Norrie disease gene in X linked pedigrees and with linkage to the EVR1 locus at 11q13 in autosomal dominant cases. A large autosomal dominant FEVR family was studied, both clinically and by linkage analysis, to determine whether it differed from the known forms of FEVR. Affected members and obligate gene carriers from this family were examined by slit lamp biomicroscopy, indirect ophthalmoscopy, and in some cases fluorescein angiography. Patient DNAs were genotyped for markers at the EVR1 locus on chromosome 11q13. The clinical evaluation in this family is consistent with previous descriptions of FEVR pedigrees, but linkage analysis proves that it has a form of FEVR genetically distinct from the EVR1 locus on 11q. This proves that there are at least three different loci associated with comparable FEVR phenotypes, a situation similar to that existing for many forms of retinal degeneration.

Mutations of the a mating-type gene in Neurospora crassa

International Nuclear Information System (INIS)

Griffiths, A.J.F.; DeLange, A.M.

1978-01-01

In Neurospora, the mating-type locus controls both mating (A + a is fertile) and heterokaryosis (A + a is incompatible). The two alleles appear stable: no novel fertility reactions have ever beeen reported, and attempts to separate fertility and heterokaryon incompatibility functions by recombination have been unsuccessful. In the present approach the locus was studied through a mutational analysis of heterokaryon incompatibility function. A selection system was used that detects vigorous (A + a) heterokaryotic colonies against a background of inhibited growth. Twenty-five mutants of an a strain were produced following mutagenic treatment with uv and NG: 15 were viable as homokaryons and 10 were not. All but one were infertile, but most showed an abortive mating reaction involving the production of barren, well-developed perithecia with A and (surprisingly) a testers. None of the mutants complement each other to restore fertility. Seven mutants have been mapped to the mating-type locus region of chromosome 1. Restoration of fertility was used to detect revertants, and these were found in five out of the eight mutants tested. (A dose response was observed). In four cases incompatibility was fully restored and in one case it was not. The results suggest two positive actions of the locus when in heterozygous (A/a) combination (the stimulation of some stage of ascus production and the inhibition of vegetative heterokaryosis), and one positive action in homozygous combinations

Mutations in the maize zeta-carotene desaturase gene lead to viviparous kernel.

Directory of Open Access Journals (Sweden)

Yan Chen

Full Text Available Preharvest sprouting reduces the maize quality and causes a significant yield loss in maize production. vp-wl2 is a Mutator (Mu-induced viviparous mutant in maize, causing white or pale yellow kernels, dramatically reduced carotenoid and ABA content, and a high level of zeta-carotene accumulation. Here, we reported the cloning of the vp-wl2 gene using a modified digestion-ligation-amplification method (DLA. The results showed that an insertion of Mu9 in the first intron of the zeta-carotene desaturase (ZDS gene results in the vp-wl2 mutation. Previous studies have suggested that ZDS is likely the structural gene of the viviparous9 (vp9 locus. Therefore, we performed an allelic test using vp-wl2 and three vp9 mutants. The results showed that vp-wl2 is a novel allele of the vp9 locus. In addition, the sequences of ZDS gene were identified in these three vp9 alleles. The vp-wl2 mutant gene was subsequently introgressed into four maize inbred lines, and a viviparous phenotype was observed with yield losses from 7.69% to 13.33%.

Genetic polymorphisms and mutation rates of 27 Y-chromosomal STRs in a Han population from Guangdong Province, Southern China.

Science.gov (United States)

Wang, Ying; Zhang, Yong-Ji; Zhang, Chu-chu; Li, Ran; Yang, Yang; Ou, Xue-Ling; Tong, Da-yue; Sun, Hong-Yu

2016-03-01

In this study, we collected blood samples from 1033 father-son pairs of a Han population from Guangdong Province, Southern China, of which 1007 fathers were unrelated male individuals. All together, 2040 male individuals were analyzed at 27 Y-chromosomal short tandem repeats (Y-STRs) with Yfiler(®) Plus system. A total of 1003 different haplotypes were observed among 1007 unrelated fathers, with the overall haplotype diversity (HD) 0.999992 and discrimination capacity (DC) 0.996. The gene diversity (GD) values for the 27 Y-STR loci ranged from 0.4400 at DYS438 to 0.9597 at DYS385a/b. 11 off-ladder alleles and 25 copy number variants were detected in 1007 males. Population relationships were analyzed by comparison with 19 other worldwide populations. With 27,920 allele transfers in 1033 father-son pairs, 124 mutation events occurred, of which 118 were one-step mutations and 6 were two-step mutations. Eleven father-son pairs were found to have mutations at two loci, while one pair at three loci. The estimated locus-specific mutation rates varied from 0 to 1.74×10(-2), with an average estimated mutation rate 4.4×10(-3) (95%CI: 3.7×10(-3) to 5.3×10(-3)). Mutations were most frequently observed at three rapidly mutating Y-STRs (RM Y-STRs), DYS576, DYS518 and DYS627. However, at DYS570, DYS449 and DYF387S1 loci, which were also described as RM Y-STRs, the mutation rates in Guangdong Han population were not as high as estimated in other populations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Mutation analysis of SLC26A4 for Pendred syndrome and nonsyndromic hearing loss by high-resolution melting

DEFF Research Database (Denmark)

Chen, Neng; Tranebjærg, Lisbeth; Rendtorff, Nanna Dahl

2011-01-01

Pendred syndrome and DFNB4 (autosomal recessive nonsyndromic congenital deafness, locus 4) are associated with autosomal recessive congenital sensorineural hearing loss and mutations in the SLC26A4 gene. Extensive allelic heterogeneity, however, necessitates analysis of all exons and splice sites...

Mutation frequencies in male mice and the estimation of genetic hazards of radiation in men

International Nuclear Information System (INIS)

Russell, W.L.; Kelly, E.M.

1982-01-01

Estimation of the genetic hazards of ionizing radiation in men is based largely on the frequency of transmitted specific-locus mutations induced in mouse spermatogonial stem cells at low radiation dose rates. The publication of new data on this subject has permitted a fresh review of all the information available. The data continue to show no discrepancy from the interpretation that, although mutation frequency decreases markedly as dose rate is decreased from 90 to 0.8 R/min (1 R = 2.6 x 10/sup -4/ coulombs/kg) there seems to be no further change below 0.8 R/min over the range from that dose rate to 0.0007 R/min. Simple mathematical models are used to compute: (a) a maximum likelihood estimate of the induced mutation frequency at the low dose rates, and (b) a maximum likelihood estimate of the ratio of this to the mutation frequency at high dose rates in the range of 72 to 90 R/min. In the application of these results to the estimation of genetic hazards of radiation in man, the former value can be used to calcualte a doubling dose - i.e., the dose of radiation that induces a mutation frequency equal to the spontaneous frequency. The doubling dose based on the low-dose-rate data compiled here is 110 R. The ratio of the mutation frequency at low dose rate to to that at high dose rate is useful when it becomes necessary to extrapolate from experimental determinations, or from human data, at high dose rates to the expected risk at low dose rates. The ratio derived from the present analysis is 0.33

Survey on the frequency of somatic mutations in A-bomb survivors

International Nuclear Information System (INIS)

Akiyama, Mitoshi

1992-01-01

Several methods have recently been established for quantitatively detecting somatic cell mutations on a specific locus using human blood cells. These methods have enabled the biological estimation of A-bomb radiation doses in surveys on somatic cell mutations. This paper outlines HPRT, GPA, and TCR assays used to measure somatic cell mutations, focusing on the outcome in A-bomb survivors. HPRT assay is based on colony formation with interleukin-2. The frequency of HPRT mutant cells was significantly increased with advancing age in A-bomb survivors and was positively correlated with the frequency of chromosomal aberrations in lymphocytes. There was also a significantly positive correlation between HPRT mutant cell frequencies and DS86 estimated doses, although the slope was slow. In GPA assay, flow cytometric measurements of fluorescence-labeled erythrocytes are used to detect somatic cell mutations. There was a positive correlation between GPA mutant cell frequencies and age in A-bomb survivors. The GPA mutant cell frequencies showed much more positive correlation with lymphocyte chromosomal aberration frequencies than the HPRT mutant cell frequencies. When anti-CD3 antibody and anti-CD4 antibody are labeled with different fluorescences and are analyzed by using flow cytometry, TCR mutant cells having CD3 - 4 + can be detected. When the frequency of TCR mutant cells was examined in 342 A-bomb survivors, it did not correlate with radiation doses. This implies that TCR assay may be unadequate for biological estimation of A-bomb radiation doses throughout a lifetime of A-bomb survivors, because TCR mutant cells seems to be unable to live for a long time due to national selection. (N.K.)

On the effect of certain mutations on the radiosensitivity of haploid and diploid yeast cells

International Nuclear Information System (INIS)

Sokurova, E.N.; Korogodin, V.I.

1978-01-01

Mutation ade 1-6 in haploid cell Saccharomyces cerevisiae increases half as much against radioresistance of cells. Diploid cells lacking in adenine, homozygous by ade 1-6 mutation, are nearly twice as radiosensitive as prototrophic cells. Hence ade 1-6 mutation increases radioresistance of haploid cells and decreases that of diplois. These changes in radioresistance are not connected with variations in the extrapolation number of survival curve, the ability of cells to recover from radiation damages upon cultivation in an innutrient medium, and with the inactivation form ratio. Lack of adenine influences the radioresistance of diploid yeast irrespective of whether it is or it is not affected by homo- or heterozygosity by the locus of mating type

A study on single nucleotide polymorphism of exon 7 T/C (locus 593 of platelet-activating factor acetylhydrolase gene in healthy Han population in the Shanghai region

Directory of Open Access Journals (Sweden)

Tian-bao XIA

2012-08-01

Full Text Available Objective To investigate the distribution of single nucleotide polymorphism (SNP in platelet-activating factor acetylhydrolase (PAF-AH gene exon 7 T/C (locus 593 in healthy Han population in Shanghai region and the features different from other races. Methods The SNP in PAF-AH gene exon 7 T/C (locus 593 was detected and analyzed by PCR and sequencing in 110 healthy Han people from Shanghai areas. The genotype and allele frequency were then calculated and compared with that in other races in combination with review of relevant literature. Results The amplified product of the SNP in PAF-AH gene exon 7 T/C (locus 593 was 240 bp in 110 healthy Han people, of whom 97 were with TT genotype and 13 with TC genotype, but no CC genotype was found. As to the allele frequency distribution, T type allele took the highest position, and C type followed. The genotype frequency of TT and TC was 88.2% and 11.8%, respectively, and they were markedly different from that in German population (0.95%, while not statistically significant different from that in British population (7.67%. Conclusions There exists SNP in PAF-AH gene exon 7 T/C (position 593 in healthy Han people in Shanghai region, with a higher frequency of T→C mutation. The mutational genotype frequency is found to be located at the locus 593 is 11.81%, and it is markedly different from that in German population, but not significantly different from that in British population.

One-Step Biallelic and Scarless Correction of a β-Thalassemia Mutation in Patient-Specific iPSCs without Drug Selection

Directory of Open Access Journals (Sweden)

Yali Liu

2017-03-01

Full Text Available Monogenic disorders (MGDs, which are caused by single gene mutations, have a serious effect on human health. Among these, β-thalassemia (β-thal represents one of the most common hereditary hematological diseases caused by mutations in the human hemoglobin β (HBB gene. The technologies of induced pluripotent stem cells (iPSCs and genetic correction provide insights into the treatments for MGDs, including β-thal. However, traditional approaches for correcting mutations have a low efficiency and leave a residual footprint, which leads to some safety concerns in clinical applications. As a proof of concept, we utilized single-strand oligodeoxynucleotides (ssODNs, high-fidelity CRISPR/Cas9 nuclease, and small molecules to achieve a seamless correction of the β-41/42 (TCTT deletion mutation in β thalassemia patient-specific iPSCs with remarkable efficiency. Additionally, off-target analysis and whole-exome sequencing results revealed that corrected cells exhibited a minimal mutational load and no off-target mutagenesis. When differentiated into hematopoietic progenitor cells (HPCs and then further to erythroblasts, the genetically corrected cells expressed normal β-globin transcripts. Our studies provide the most efficient and safe approach for the genetic correction of the β-41/42 (TCTT deletion in iPSCs for further potential cell therapy of β-thal, which represents a potential therapeutic avenue for the gene correction of MGD-associated mutants in patient-specific iPSCs.

Analysis of the rdd locus in chicken: a model for human retinitis pigmentosa.

Science.gov (United States)

Burt, David W; Morrice, David R; Lester, Douglas H; Robertson, Graeme W; Mohamed, Moin D; Simmons, Ian; Downey, Louise M; Thaung, Caroline; Bridges, Leslie R; Paton, Ian R; Gentle, Mike; Smith, Jacqueline; Hocking, Paul M; Inglehearn, Chris F

2003-04-30

To identify the locus responsible for the blind mutation rdd (retinal dysplasia and degeneration) in chickens and to further characterise the rdd phenotype. The eyes of blind and sighted birds were subjected to ophthalmic, morphometric and histopathological examination to confirm and extend published observations. Electroretinography was used to determine age of onset. Birds were crossed to create pedigrees suitable for genetic mapping. DNA samples were obtained and subjected to a linkage search. Measurement of IOP, axial length, corneal diameter, and eye weight revealed no gross morphological changes in the rdd eye. However, on ophthalmic examination, rdd homozygotes have a sluggish pupillary response, atrophic pecten, and widespread pigmentary disturbance that becomes more pronounced with age. Older birds also have posterior subcapsular cataracts. At three weeks of age, homozygotes have a flat ERG indicating severe loss of visual function. Pathological examination shows thinning of the RPE, ONL, photoreceptors and INL, and attenuation of the ganglion cell layer. From 77 classified backcross progeny, 39 birds were blind and 38 sighted. The rdd mutation was shown to be sex-linked and not autosomal as previously described. Linkage analysis mapped the rdd locus to a small region of the chicken Z chromosome with homologies to human chromosomes 5q and 9p. Ophthalmic, histopathologic, and electrophysiological observations suggest rdd is similar to human recessive retinitis pigmentosa. Linkage mapping places rdd in a region homologous to human chromosomes 9p and 5q. Candidate disease genes or loci include PDE6A, WGN1, and USH2C. This is the first use of genetic mapping in a chicken model of human disease.

Mutants in the host-pathogen system barley-powdery mildew

International Nuclear Information System (INIS)

Joergensen, J.H.

1989-10-01

Mutation induction was used to analyse the host/pathogen interaction of barley and Erysiphe graminis. By irradiation or chemical mutagens, a number of similar mutations were induced in the ml-o gene (locus) of barley. The mutants had non-specific and durable resistance, which is rather uncommon. Studies revealed, that in spite of their similarity (the same mutated locus, monogenic recessive inheritance), the mutants were not identical and represent unique sources of disease resistant germ plasm. To study more fundamentally the interference of induced mutations in host/pathogen interactions, barley carrying the dominant resistance gene M1-a 12 was irradiated to mutate this gene. Instead of the expected ''monogenic recessive susceptibility'', several different mutational events inside and outside the locus were found to modify the resistance towards a more or less susceptible reaction. A third interesting approach was to induce mutations in the pathogen and thus create new virulence genes. The result, that no true mutation towards virulence was obtained in extremely large populations, deserves attention and further study to be sure about its implication. 13 refs

Correlation between chromosome 9p21 locus deletion and prognosis in clinically localized prostate cancer.

Science.gov (United States)

Barros, Érika Aparecida Felix de; Pontes-Junior, José; Reis, Sabrina Thalita; Lima, Amanda Eunice Ramos; Souza, Isida C; Salgueiro, Jose Lucas; Fontes, Douglas; Dellê, Humberto; Coelho, Rafael Ferreira; Viana, Nayara Izabel; Leite, Kátia Ramos Moreira; Nahas, William C; Srougi, Miguel

2017-05-04

Some studies have reported that deletions at chromosome arm 9p occur frequently and represent a critical step in carcinogenesis of some neoplasms. Our aim was to evaluate the deletion of locus 9p21 and chromosomes 3, 7 and 17 in localized prostate cancer (PC) and correlate these alterations with prognostic factors and biochemical recurrence after surgery. We retrospectively evaluated surgical specimens from 111 patients with localized PC who underwent radical prostatectomy. Biochemical recurrence was defined as a prostate-specific antigen (PSA) >0.2 ng/mL and the mean postoperative follow-up was 123 months. The deletions were evaluated using fluorescence in situ hybridization with centromeric and locus-specific probes in a tissue microarray containing 2 samples from each patient. We correlated the occurrence of any deletion with pathological stage, Gleason score, ISUP grade group, PSA and biochemical recurrence. We observed a loss of any probe in only 8 patients (7.2%). The most common deletion was the loss of locus 9p21, which occurred in 6.4% of cases. Deletions of chromosomes 3, 7 and 17 were observed in 2.3%, 1.2% and 1.8% patients, respectively. There was no correlation between chromosome loss and Gleason score, ISUP, PSA or stage. Biochemical recurrence occurred in 83% cases involving 9p21 deletions. Loss of 9p21 locus was significantly associated with time to recurrence (p = 0.038). We found low rates of deletion in chromosomes 3, 7 and 17 and 9p21 locus. We observed that 9p21 locus deletion was associated with worse prognosis in localized PC treated by radical prostatectomy.

NR2E3 mutations in enhanced S-cone sensitivity syndrome (ESCS), Goldmann-Favre syndrome (GFS), clumped pigmentary retinal degeneration (CPRD), and retinitis pigmentosa (RP).

Science.gov (United States)

Schorderet, Daniel F; Escher, Pascal

2009-11-01

NR2E3, also called photoreceptor-specific nuclear receptor (PNR), is a transcription factor of the nuclear hormone receptor superfamily whose expression is uniquely restricted to photoreceptors. There, its physiological activity is essential for proper rod and cone photoreceptor development and maintenance. Thirty-two different mutations in NR2E3 have been identified in either homozygous or compound heterozygous state in the recessively inherited enhanced S-cone sensitivity syndrome (ESCS), Goldmann-Favre syndrome (GFS), and clumped pigmentary retinal degeneration (CPRD). The clinical phenotype common to all these patients is night blindness, rudimental or absent rod function, and hyperfunction of the "blue" S-cones. A single p.G56R mutation is inherited in a dominant manner and causes retinitis pigmentosa (RP). We have established a new locus-specific database for NR2E3 (www.LOVD.nl/eye), containing all reported mutations, polymorphisms, and unclassified sequence variants, including novel ones. A high proportion of mutations are located in the evolutionarily-conserved DNA-binding domains (DBDs) and ligand-binding domains (LBDs) of NR2E3. Based on homology modeling of these NR2E3 domains, we propose a structural localization of mutated residues. The high variability of clinical phenotypes observed in patients affected by NR2E3-linked retinal degenerations may be caused by different disease mechanisms, including absence of DNA-binding, altered interactions with transcriptional coregulators, and differential activity of modifier genes.

Mutational specificity of alkylating agents and the influence of DNA repair

Energy Technology Data Exchange (ETDEWEB)

Horsfall, M.J.; Gordon, A.J.; Burns, P.A.; Zielenska, M.; van der Vliet, G.M.; Glickman, B.W. (York Univ., Toronto, Ontario (Canada))

1990-01-01

Alkylating treatments predominantly induce G:C = greater than A:T transitions, consistent with the predicted significance of the miscoding potential of the O6-alG lesion. However, the frequency and distribution of these events induced by any one compound may be diagnostic. SN1 agents that act via an alkyldiazonium cation, such as the N-nitroso compounds, preferentially generate G:C = greater than A:T transitions at 5'-RG-3' sites, while the more SN2 alkylsulfates and alkylalkane-sulfonates do not. The precise nature of this site bias and the possibility of strand bias are target dependent. The extent of this site bias and the contribution of other base substitutions are substituent size dependent. A similar 5'-RT-3' effect is seen for A:T = greater than G:C transitions, presumably directed by O4-alT lesions. The 5'-RG-3' effect, at least, likely reflects a deposition specificity arising from some aspect of helix geometry, although it may be further exaggerated by alkylation-specific repair. Excision repair appears to preferentially reduce the occurrence of ethylation-induced G:C = greater than A:T and A:T = greater than G:C transitions at sites flanked by A:T base pairs. This may be due to an enhancement of the helical distortion imposed by damage at such positions. A similar effect is not seen for methylation-induced mutations and in the case of propyl adducts, the influence of excision repair on the ultimate distribution of mutation cannot be as easily defined with respect to neighbouring sequence. 199 references.

Variations in the occurrence of specific rpoB mutations in rifampicin-resistant Mycobacterium tuberculosis isolates from patients of different ethnic groups in Kuwait.

Science.gov (United States)

Ahmad, Suhail; Al-Mutairi, Noura M; Mokaddas, Eiman

2012-05-01

Frequency of resistance-conferring mutations vary among isoniazid- and ethambutol-resistant Mycobacterium tuberculosis isolates obtained from patients of various ethnic groups. This study was aimed to determine the occurrence of specific rpoB mutations in rifampicin-resistant M. tuberculosis isolates from tuberculosis patients of various ethnic groups in Kuwait. Rifampicin-resistant M. tuberculosis isolates (n=119) from South Asian (n=55), Southeast Asian (n=23), Middle Eastern (n=39) and other (n=2) patients and 107 rifampicin-susceptible isolates were tested. Mutations in rpoB were detected by DNA sequencing. Polymorphisms at katG463 and gyrA95 were detected by PCR-RFLP for genetic group assignment. None of rifampicin-susceptible but 116 of 119 rifampicin-resistant isolates showed rpoB mutation(s). Mutations among isolates from South Asian patients were distributed at rpoB516 (20%), rpoB526 (24%) and rpoB531 (27%) while 78 and 51 per cent of isolates from Southeast Asian and Middle Eastern patients, respectively, contained a mutated rpoB531. All isolates with rpoB N-terminal and cluster II mutations were obtained from Middle Eastern and South Asian patients. Most isolates from South Asian (84%) and Southeast Asian (70%) patients belonged to genetic group I while nearly all remaining isolates belonged to genetic group II. Isolates from Middle Eastern patients were distributed among genetic group I (46%), genetic group II (33%) and genetic group III (21%). The occurrence of specific rpoB mutations varied considerably in rifampicin-resistant M. tuberculosis isolates obtained from patients of different ethnic groups within the same country. The present data have important implications for designing region-specific rapid methods for detecting majority of rifampicin-resistant strains.

WASP: a Web-based Allele-Specific PCR assay designing tool for detecting SNPs and mutations

Directory of Open Access Journals (Sweden)

Assawamakin Anunchai

2007-08-01

Full Text Available Abstract Background Allele-specific (AS Polymerase Chain Reaction is a convenient and inexpensive method for genotyping Single Nucleotide Polymorphisms (SNPs and mutations. It is applied in many recent studies including population genetics, molecular genetics and pharmacogenomics. Using known AS primer design tools to create primers leads to cumbersome process to inexperience users since information about SNP/mutation must be acquired from public databases prior to the design. Furthermore, most of these tools do not offer the mismatch enhancement to designed primers. The available web applications do not provide user-friendly graphical input interface and intuitive visualization of their primer results. Results This work presents a web-based AS primer design application called WASP. This tool can efficiently design AS primers for human SNPs as well as mutations. To assist scientists with collecting necessary information about target polymorphisms, this tool provides a local SNP database containing over 10 million SNPs of various populations from public domain databases, namely NCBI dbSNP, HapMap and JSNP respectively. This database is tightly integrated with the tool so that users can perform the design for existing SNPs without going off the site. To guarantee specificity of AS primers, the proposed system incorporates a primer specificity enhancement technique widely used in experiment protocol. In particular, WASP makes use of different destabilizing effects by introducing one deliberate 'mismatch' at the penultimate (second to last of the 3'-end base of AS primers to improve the resulting AS primers. Furthermore, WASP offers graphical user interface through scalable vector graphic (SVG draw that allow users to select SNPs and graphically visualize designed primers and their conditions. Conclusion WASP offers a tool for designing AS primers for both SNPs and mutations. By integrating the database for known SNPs (using gene ID or rs number

Detection of a molecular deletion at the DXS732 locus in a patient with X-linked hypohidrotic ectodermal dysplasia (EDA), with the identification of a unique junctional fragment

Energy Technology Data Exchange (ETDEWEB)

Zonana, J.; Gault, J.; Jones, M.; Browne, D.; Litt, M. (Oregon Health Sciences Univ., Portland (United States)); Davies, K.J.P.; Clarke, A.; Thomas, N.S.T. (Univ. of Wales, Cardiff (United Kingdom)); Brockdorff, N.; Rastan, S. (Medical Research Council Clinical Research Centre, Harrow (United Kingdom))

1993-01-01

X-linked hypohidrotic ectodermal dysplasia (EDA) has been localized to the Xq12-q13.1. A panel of genomic DNA samples from 80 unrelated males with EDA has been screened for deletions at seven genetic loci within the Xq12-13 region. A single individual was identified with a deletion at the DXS732 locus by hybridization with the mouse genomic probe pcos169E/4. This highly conserved DNA probe is from locus DXCrc169, which is tightly linked to the Ta locus, the putative mouse homologue of EDA. The proband had the classical phenotype of EDA, with no other phenotypic abnormalities, and a normal cytogenetic analysis. A human genomic DNA clone, homologous to pcos169E/4, was isolated from a human X-chromosome cosmid library. On hybridization with the cosmid, the proband was found to be only partially deleted at the DXS732 locus, with a unique junctional fragment identified in the proband and in three of his maternal relatives. This is the first determination of carrier status for EDA in females, by direct mutation analysis. Failure to detect deletion of the other loci tested in the proband suggests that the DXS732 locus is the closest known locus to the EDA gene. Since the DXS732 locus contains a highly conserved sequence, it must be considered to be a candidate locus for the EDA gene itself. 18 refs., 3 figs., 1 tab.

Lack of GNAQ and GNA11 germ-line mutations in familial melanoma pedigrees with uveal melanoma or blue nevi

Directory of Open Access Journals (Sweden)

Jason Ezra Hawkes

2013-06-01

Full Text Available Approximately 10% of melanoma cases are familial, but only 25-40% of familial melanoma cases can be attributed to germ-line mutations in the CDKN2A - the most significant high-risk melanoma susceptibility locus identified to date. The pathogenic mutation(s in most of the remaining familial melanoma pedigrees have not yet been identified. The most common mutations in nevi and sporadic melanoma are found in BRAF and NRAS, both of which result in constitutive activation of the MAPK pathway. However, these mutations are not found in uveal melanomas or the intradermal melanocytic proliferations known as blue nevi. Rather, multiple studies report a strong association between these lesions and somatic mutations in Guanine nucleotide-binding protein G(q subunit alpha (GNAQ, Guanine nucleotide-binding protein G(q subunit alpha-11 (GNA11 and BRCA1 associated protein-1 (BAP1. Recently, germ-line mutations in BAP1, the gene encoding a tumor suppressing deubiquitinating enzyme, have been associated with predisposition to a variety of cancers including uveal melanoma, but no studies have examined the association of germ-line mutations in GNAQ and GNA11 with uveal melanoma and blue nevi. We have now done so by sequencing exon 5 of both of these genes in 13 unique familial melanoma pedigrees, members of which have had either uveal or cutaneous melanoma and/or blue nevi. Germ-line DNA from a total of 22 individuals was used for sequencing; however no deleterious mutations were detected. Nevertheless, such candidate gene studies and the discovery of novel germ-line mutations associated with an increased MM susceptibility can lead to a better understanding of the pathways involved in melanocyte transformation, formulation of risk assessment, and the development of specific drug therapies.

Exploring Learner Autonomy: Language Learning Locus of Control in Multilinguals

Science.gov (United States)

Peek, Ron

2016-01-01

By using data from an online language learning beliefs survey (n?=?841), defining language learning experience in terms of participants' multilingualism, and using a domain-specific language learning locus of control (LLLOC) instrument, this article examines whether more experienced language learners can also be seen as more autonomous language…

Variable myopathic presentation in a single family with novel skeletal RYR1 mutation.

Directory of Open Access Journals (Sweden)

Ruben Attali

Full Text Available We describe an autosomal recessive heterogeneous congenital myopathy in a large consanguineous family. The disease is characterized by variable severity, progressive course in 3 of 4 patients, myopathic face without ophthalmoplegia and proximal muscle weakness. Absence of cores was noted in all patients. Genome wide linkage analysis revealed a single locus on chromosome 19q13 with Zmax = 3.86 at θ = 0.0 and homozygosity of the polymorphic markers at this locus in patients. Direct sequencing of the main candidate gene within the candidate region, RYR1, was performed. A novel homozygous A to G nucleotide substitution (p.Y3016C within exon 60 of the RYR1 gene was found in patients. ARMS PCR was used to screen for the mutation in all available family members and in an additional 150 healthy individuals. This procedure confirmed sequence analysis and did not reveal the A to G mutation (p.Y3016C in 300 chromosomes from healthy individuals. Functional analysis on EBV immortalized cell lines showed no effect of the mutation on RyR1 pharmacological activation or the content of intracellular Ca(2+ stores. Western blot analysis demonstrated a significant reduction of the RyR1 protein in the patient's muscle concomitant with a reduction of the DHPRα1.1 protein. This novel mutation resulting in RyR1 protein decrease causes heterogeneous clinical presentation, including slow progression course and absence of centrally localized cores on muscle biopsy. We suggest that RYR1 related myopathy should be considered in a wide variety of clinical and pathological presentation in childhood myopathies.

Tuning the specificity of a Two-in-One Fab against three angiogenic antigens by fully utilizing the information of deep mutational scanning.

Science.gov (United States)

Koenig, Patrick; Sanowar, Sarah; Lee, Chingwei V; Fuh, Germaine

Monoclonal antibodies developed for therapeutic or diagnostic purposes need to demonstrate highly defined binding specificity profiles. Engineering of an antibody to enhance or reduce binding to related antigens is often needed to achieve the desired biologic activity without safety concern. Here, we describe a deep sequencing-aided engineering strategy to fine-tune the specificity of an angiopoietin-2 (Ang2)/vascular endothelial growth factor (VEGF) dual action Fab, 5A12.1 for the treatment of age-related macular degeneration. This antibody utilizes overlapping complementarity-determining region (CDR) sites for dual Ang2/VEGF interaction with K D in the sub-nanomolar range. However, it also exhibits significant (K D of 4 nM) binding to angiopoietin-1, which has high sequence identity with Ang2. We generated a large phage-displayed library of 5A12.1 Fab variants with all possible single mutations in the 6 CDRs. By tracking the change of prevalence of each mutation during various selection conditions, we identified 35 mutations predicted to decrease the affinity for Ang1 while maintaining the affinity for Ang2 and VEGF. We confirmed the specificity profiles for 25 of these single mutations as Fab protein. Structural analysis showed that some of the Fab mutations cluster near a potential Ang1/2 epitope residue that differs in the 2 proteins, while others are up to 15 Å away from the antigen-binding site and likely influence the binding interaction remotely. The approach presented here provides a robust and efficient method for specificity engineering that does not require prior knowledge of the antigen antibody interaction and can be broadly applied to antibody specificity engineering projects.

The effect of defective DNA double-strand break repair on mutations and chromosome aberrations in the Chinese hamster cell mutant XR-V15B

International Nuclear Information System (INIS)

Helbig, R.; Speit, G.; Zdzienicka, M.Z.

1995-01-01

The radiosensitive Chinese hamster cell line XR-V15B was used to study the effect of decreased rejoining of DNA double-strand breaks (DSBs) on gene mutations and chromosome aberrations. XR-V15B cells are hypersensitive to the cytotoxic effects of neocarzinostatin (NCS) and methyl methanesulfonate (MMS). Both mutagens induced more chromosome aberrations in XR-V15B cells than in the parental cell strain. The clastogenic action of NCS was characterized by the induction of predominantly chromosome-type aberrations in cells of both strains, whereas MMS induced mainly chromatid aberrations. The frequency of induced gene mutations at the hprt locus was not increased compared to the parental V79 cells when considering the same survival level. Molecular analysis by multiplex polymerase chain reaction (PCR) of mutants induced by NCS revealed a high frequency of deletions in cells of both cell lines. Methyl methane-sulfonate induced mainly mutations without visible change in the PCR pattern, which probably represent point mutations. Our findings suggest a link between a defect in DNA DSB repair and increased cytotoxic and clastogenic effects. However, a decreased ability to rejoin DNA DSBs does not seem to influence the incidence and types of gene mutations at the hprt locus induced by NCS and MMS. 28 refs., 4 figs., 3 tabs

Updated listing of haplotypes at the human phenylalanine hydroxylase (PAH) locus

Energy Technology Data Exchange (ETDEWEB)

Eisensmith, R.C.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (United States))

1992-12-01

Analysis of mutant PAH chromosomes has identified approximately 60 different single-base substitutions and deletions within the PAH locus. Nearly all of these molecular lesions are in strong linkage disequilibrium with specific RFLP haplotypes in different ethnic populations. Thus, haplotype analysis is not only useful for diagnostic purposes but is proving to be a valuable tool in population genetic studies of the origin and spread of phenylketonuria alleles in human populations. PCR-based methods have been developed to detect six of the eight polymorphic restriction sites used for determination of RFLP haplotypes at the PAH locus. A table of the proposed expanded haplotypes is given.

Work-family conflict, locus of control, and women's well-being: tests of alternative pathways.

Science.gov (United States)

Noor, Noraini M

2002-10-01

The author tested for the 3 possible pathways (i.e., direct, moderator, and mediator effects) in which locus of control can influence the relationship between work-family conflict and well-being. The author predicted that work-family conflict would be negatively correlated with well-being. In a sample of 310 Malaysian employed women with families, work-family conflict was a significant predictor of both job satisfaction and distress--negatively related to job satisfaction and positively related to symptoms of distress. More important, the results provided support for the effects of all 3 pathways of control on the relationship between work-family conflict and well-being, depending on the outcome measure: For job satisfaction, locus of control had direct effects, acted as a partial mediator, and played a significant moderating role. In contrast, only the direct effect of locus of control predicted distress. The author discusses those findings with reference to the literature on work-family conflict, locus of control, and the issue of stress-distress specificity.

Stable, Nonviral Expression of Mutated Tumor Neoantigen-specific T-cell Receptors Using the Sleeping Beauty Transposon/Transposase System

Science.gov (United States)

Deniger, Drew C; Pasetto, Anna; Tran, Eric; Parkhurst, Maria R; Cohen, Cyrille J; Robbins, Paul F; Cooper, Laurence JN; Rosenberg, Steven A

2016-01-01

Neoantigens unique to each patient's tumor can be recognized by autologous T cells through their T-cell receptor (TCR) but the low frequency and/or terminal differentiation of mutation-specific T cells in tumors can limit their utility as adoptive T-cell therapies. Transfer of TCR genes into younger T cells from peripheral blood with a high proliferative potential could obviate this problem. We generated a rapid, cost-effective strategy to genetically engineer cancer patient T cells with TCRs using the clinical Sleeping Beauty transposon/transposase system. Patient-specific TCRs reactive against HLA-A*0201-restriced neoantigens AHNAKS2580F or ERBB2H473Y or the HLA-DQB*0601-restricted neoantigen ERBB2IPE805G were assembled with murine constant chains and cloned into Sleeping Beauty transposons. Patient peripheral blood lymphocytes were coelectroporated with SB11 transposase and Sleeping Beauty transposon, and transposed T cells were enriched by sorting on murine TCRβ (mTCRβ) expression. Rapid expansion of mTCRβ+ T cells with irradiated allogeneic peripheral blood lymphocytes feeders, OKT3, interleukin-2 (IL-2), IL-15, and IL-21 resulted in a preponderance of effector (CD27−CD45RA−) and less-differentiated (CD27+CD45RA+) T cells. Transposed T cells specifically mounted a polyfunctional response against cognate mutated neoantigens and tumor cell lines. Thus, Sleeping Beauty transposition of mutation-specific TCRs can facilitate the use of personalized T-cell therapy targeting unique neoantigens. PMID:26945006

Soft sweeps III: the signature of positive selection from recurrent mutation.

Directory of Open Access Journals (Sweden)

Pleuni S Pennings

2006-12-01

Full Text Available Polymorphism data can be used to identify loci at which a beneficial allele has recently gone to fixation, given that an accurate description of the signature of selection is available. In the classical model that is used, a favored allele derives from a single mutational origin. This ignores the fact that beneficial alleles can enter a population recurrently by mutation during the selective phase. In this study, we present a combination of analytical and simulation results to demonstrate the effect of adaptation from recurrent mutation on summary statistics for polymorphism data from a linked neutral locus. We also analyze the power of standard neutrality tests based on the frequency spectrum or on linkage disequilibrium (LD under this scenario. For recurrent beneficial mutation at biologically realistic rates, we find substantial deviations from the classical pattern of a selective sweep from a single new mutation. Deviations from neutrality in the level of polymorphism and in the frequency spectrum are much less pronounced than in the classical sweep pattern. In contrast, for levels of LD, the signature is even stronger if recurrent beneficial mutation plays a role. We suggest a variant of existing LD tests that increases their power to detect this signature.

Reciprocal mouse and human limb phenotypes caused by gain- and loss-of-function mutations affecting Lmbr1.

OpenAIRE

Clark, R M; Marker, P C; Roessler, E; Dutra, A; Schimenti, J C; Muenke, M; Kingsley, D M

2001-01-01

The major locus for dominant preaxial polydactyly in humans has been mapped to 7q36. In mice the dominant Hemimelic extra toes (Hx) and Hammertoe (Hm) mutations map to a homologous chromosomal region and cause similar limb defects. The Lmbr1 gene is entirely within the small critical intervals recently defined for both the mouse and human mutations and is misexpressed at the exact time that the mouse Hx phenotype becomes apparent during limb development. This result suggests that Lmbr1 may un...

LOCUS OF CONTROL AND JOB SATISFACTION: PSU EMPLOYEES

Directory of Open Access Journals (Sweden)

Lakshman Vijayashree

2011-11-01

Full Text Available Previous research studies have demonstrated that internal/external locus of control impacts jobsatisfaction. The present study thus aims to analyze type of locus of control and its relation with jobsatisfaction. The study will be of great help for organization to understand and know what type oflocus of control their employees has and how it has an impact on job satisfaction.The objectives of this study were: 1- To identify the type of Locus of Control (i.e. Internal orExternal present in Public Sector Units (PSU in Bangalore and 2- To analyze the impact of differenttype of Locus of Control on job satisfaction of PSU Employees. Further hypothesis was also set tocheck the relationship between locus of control and job satisfaction. In addition, the relationshipbetween different demographic factors was also examined. The tool used for this study was LocoInventory. The concept of locus of control by Levenson (1972 was used to develop Loco Inventory(Locus of Control in Organization Inventory. The survey used a questionnaire, which had thirty fivestatements which highlights the factors that determine the locus of control and job satisfaction levelof the employees. The Ratio, ANOVA, and Correlation analysis were used as statistical techniquesfor analysis.The results indicate that there is a positive correlation between internal locus of control and jobsatisfaction as well as between External (other locus of control and job satisfaction. And in case ofExternal (Chance locus of control and job satisfaction there exists partial positive correlation. As perthis study Job satisfaction level among the employees is also good as the mean is 17, which is closerto maximum scale value of 25. As per ANOVA table there is a significant variance betweeninternality and age as well as between externality (chance and age. There is no significantrelationship between internality and demographic factors like gender and education. There is nosignificant relationship between

The Ties that Bind (the Igh Locus).

Science.gov (United States)

Krangel, Michael S

2016-05-01

Immunoglobulin heavy-chain locus V(D)J recombination requires a 3D chromatin organization which permits widely distributed variable (V) gene segments to contact distant diversity (D) and joining (J) gene segments. A recent study has identified key nodes in the locus interactome, paving the way for new molecular insights into how the locus is configured for recombination. Copyright © 2016 Elsevier Ltd. All rights reserved.

Identification of two new mutations in the GPR98 and the PDE6B genes segregating in a Tunisian family.

Science.gov (United States)

Hmani-Aifa, Mounira; Benzina, Zeineb; Zulfiqar, Fareeha; Dhouib, Houria; Shahzadi, Amber; Ghorbel, Abdelmonem; Rebaï, Ahmed; Söderkvist, Peter; Riazuddin, Sheikh; Kimberling, William J; Ayadi, Hammadi

2009-04-01

Autosomal recessive retinitis pigmentosa (ARRP) is a genetically heterogeneous disorder. ARRP could be associated with extraocular manifestations that define specific syndromes such as Usher syndrome (USH) characterized by retinal degeneration and congenital hearing loss (HL). The USH type II (USH2) associates RP and mild-to-moderate HL with preserved vestibular function. At least three genes USH2A, the very large G-protein-coupled receptor, GPR98, and DFNB31 are responsible for USH2 syndrome. Here, we report on the segregation of non-syndromic ARRP and USH2 syndrome in a consanguineous Tunisian family, which was previously used to define USH2B locus. With regard to the co-occurrence of these two different pathologies, clinical and genetic reanalysis of the extended family showed (i) phenotypic heterogeneity within USH2 patients and (ii) excluded linkage to USH2B locus. Indeed, linkage analysis disclosed the cosegregation of the USH2 phenotype with the USH2C locus markers, D5S428 and D5S618, whereas the ARRP perfectly segregates with PDE6B flanking markers D4S3360 and D4S2930. Molecular analysis revealed two new missense mutations, p.Y6044C and p.W807R, occurring in GPR98 and PDE6B genes, respectively. In conclusion, our results show that the USH2B locus at chromosome 3p23-24.2 does not exist, and we therefore withdraw this locus designation. The combination of molecular findings for GPR98 and PDE6B genes enable us to explain the phenotypic heterogeneity and particularly the severe ocular affection first observed in one USH2 patient. This report presents an illustration of how consanguinity could increase familial clustering of multiple hereditary diseases within the same family.

Mutation profile of all 49 exons of the human myosin VIIA gene, and haplotype analysis, in Usher 1B families from diverse origins.

Science.gov (United States)

Adato, A; Weil, D; Kalinski, H; Pel-Or, Y; Ayadi, H; Petit, C; Korostishevsky, M; Bonne-Tamir, B

1997-10-01

Usher syndrome types I (USH1A-USH1E) are a group of autosomal recessive diseases characterized by profound congenital hearing loss, vestibular areflexia, and progressive visual loss due to retinitis pigmentosa. The human myosin VIIA gene, located on 11q14, has been shown to be responsible for Usher syndrome type 1B (USH1B). Haplotypes were constructed in 28 USH1 families by use of the following polymorphic markers spanning the USH1B locus: D11S787, D11S527, D11S1789, D11S906, D11S4186, and OMP. Affected individuals and members of their families from 12 different ethnic origins were screened for the presence of mutations in all 49 exons of the myosin VIIA gene. In 15 families myosin VIIA mutations were detected, verifying their classification as USH1B. All these mutations are novel, including three missense mutations, one premature stop codon, two splicing mutations, one frameshift, and one deletion of >2 kb comprising exons 47 and 48, a part of exon 49, and the introns between them. Three mutations were shared by more than one family, consistent with haplotype similarities. Altogether, 16 USH1B haplotypes were observed in the 15 families; most haplotypes were population specific. Several exonic and intronic polymorphisms were also detected. None of the 20 known USH1B mutations reported so far in other world populations were identified in our families.

The diabetes type 1 locus Idd6 modulates activity of CD4+CD25+ regulatory T-cells.

Science.gov (United States)

Rogner, Ute Christine; Lepault, Françoise; Gagnerault, Marie-Claude; Vallois, David; Morin, Joëlle; Avner, Philip; Boitard, Christian

2006-01-01

The genetic locus Idd6 confers susceptibility to the spontaneous development of type 1 diabetes in the NOD mouse. Our studies on disease resistance of the congenic mouse strain NOD.C3H 6.VIII showed that Idd6 influences T-cell activities in the peripheral immune system and suggest that a major mechanism by which the Idd6 locus modifies diabetes development is via modulation of regulatory T-cell activities. Our transfer experiments using total splenocytes and purified T-cells demonstrated that the locus specifically controls the efficiency of disease protection mediated by the regulatory CD4(+)CD25(+) T-cell subset. Our data also implicate the Idd6 locus in controlling the balance between infiltrating lymphocytes and antigen-presenting cells within the pancreatic islet.

Locus: mede-ontwikkelaar van inclusieve arbeidsorganisaties

NARCIS (Netherlands)

Beukema, Leni; de Lange, Annet; Wielenga-Meijer, Etty; Duijker, Theo; Hanstede, Bram

2018-01-01

in deze bijdrage wordt Locus beschreven, een netwerk waarin publieke partijen en grote, landelijk opererende bedrijven samenwerken om mensen met een afstand tot de arbeidsmarkt duurzaam aan het werk te helpen. Het hoofdstuk start met de ontstaansgeschiedenis en benadering van Locus. Vervolgens wordt

Development of a possible nonmammalian test system for radiation-induced germ-cell mutagenesis using a fish, the Japanese medaka (Oryzias latipes)

International Nuclear Information System (INIS)

Shima, A.; Shimada, A.

1991-01-01

To develop a specific-locus test (SLT) system for environmental mutagenesis using vertebrate species other than the mouse, we first established a tester stock of the fish medaka (Oryzias latipes) that is homozygous recessive at three loci. The phenotypic expression of these loci can be easily recognized early in embryonic development by observation through the transparent egg membrane. We irradiated wild-type males with 137Cs gamma-rays to determine the dose-response relationships for dominant lethal and specific-locus mutations induced in sperm, spermatids, and spermatogonia. Through observation of 322,666 loci in control offspring and 374,026 loci in offspring obtained from 0.64-, 4.75-, or 9.50-Gy-irradiated gametes, specific-locus mutations were phenotypically detected during early development. These putative mutations, designated total mutation, can be recognized only in embryos of oviparous animals. The developmental fate of these mutant embryos was precisely followed. During subsequent embryonic development, a large fraction died and thus was unavailable for test-crossing, which was used to identify viable mutations. Our medaka SLT system demonstrates that the vast majority of total mutations is associated with dominant lethal mutations. Thus far only one spontaneous viable mutation has been observed, so that all doubling calculations involving this endpoint carry a large error. With these reservations, however, we conclude that the quantitative data so far obtained from the medaka SLT are quite comparable to those from the mouse SLT and, hence, indicate the validity of the medaka SLT as a possible nonmammalian test system

An evolutionary reduction principle for mutation rates at multiple Loci.

Science.gov (United States)

Altenberg, Lee

2011-06-01

A model of mutation rate evolution for multiple loci under arbitrary selection is analyzed. Results are obtained using techniques from Karlin (Evolutionary Biology, vol. 14, pp. 61-204, 1982) that overcome the weak selection constraints needed for tractability in prior studies of multilocus event models.A multivariate form of the reduction principle is found: reduction results at individual loci combine topologically to produce a surface of mutation rate alterations that are neutral for a new modifier allele. New mutation rates survive if and only if they fall below this surface-a generalization of the hyperplane found by Zhivotovsky et al. (Proc. Natl. Acad. Sci. USA 91, 1079-1083, 1994) for a multilocus recombination modifier. Increases in mutation rates at some loci may evolve if compensated for by decreases at other loci. The strength of selection on the modifier scales in proportion to the number of germline cell divisions, and increases with the number of loci affected. Loci that do not make a difference to marginal fitnesses at equilibrium are not subject to the reduction principle, and under fine tuning of mutation rates would be expected to have higher mutation rates than loci in mutation-selection balance.Other results include the nonexistence of 'viability analogous, Hardy-Weinberg' modifier polymorphisms under multiplicative mutation, and the sufficiency of average transmission rates to encapsulate the effect of modifier polymorphisms on the transmission of loci under selection. A conjecture is offered regarding situations, like recombination in the presence of mutation, that exhibit departures from the reduction principle. Constraints for tractability are: tight linkage of all loci, initial fixation at the modifier locus, and mutation distributions comprising transition probabilities of reversible Markov chains.

Examining the relationship between health locus of control and God Locus of Health Control: Is God an internal or external source?

Science.gov (United States)

Boyd, Joni M; Wilcox, Sara

2017-11-01

For many people, the influence of believing in a higher power can elicit powerful effects. This study examined the relationship between God control, health locus of control, and frequency of religious attendance within 838 college students through online surveys. Regression analysis showed that chance and external locus of control and frequency of religious attendance were significant and positive predictors of God Locus of Health Control. The association of powerful others external locus of control and God Locus of Health Control differed by race (stronger in non-Whites than Whites) and somewhat by gender (stronger in women than men). For some people, the role of a supreme being, or God, should be considered when designing programs for improving health behaviors.

Ortholog Alleles at Xa3/Xa26 Locus Confer Conserved Race-Specific Resistance against Xanthomonas oryzae in Rice

Institute of Scientific and Technical Information of China (English)

Hong-Jing Li; Xiang-Hua Li; Jing-Hua Xiao; Rod A. Wing; Shi-Ping Wang

2012-01-01

The rice disease resistance (R) gene Xa3/Xa26 (having also been named Xa3 and Xa26) against Xanthomonas oryzae pv.oryzae (Xoo),which causes bacterial blight disease,belongs to a multiple gene family clustered in chromosome 11 and is from an AA genome rice cultivar (Oryza sativa L.).This family encodes leucine-rich repeat (LRR) receptor kinasetype proteins.Here,we show that the orthologs (alleles) of Xa3/Xa26,Xa3/Xa26-2,and Xa3/Xa26-3,from wild Oryza species O.officinalis (CC genome) and O.minuta (BBCC genome),respectively,were also R genes against Xoo.Xa3/Xa26-2 and Xa3/Xa26-3 conferred resistance to 16 of the 18 Xoo strains examined.Comparative sequence analysis of the Xa3/Xa26 families in the two wild Oryza species showed that Xa3/Xa26-3 appeared to have originated from the CC genome of O.minuta.The predicted proteins encoded by Xa3/Xa26,Xa3/Xa26-2,and Xa3/Xa26-3 share 91-99％ sequence identity and 94-99％ sequence similarity.Transgenic plants carrying a single copy of Xa3/Xa26,Xa3/Xa26-2,or Xa3/Xa26-3,in the same genetic background,showed a similar resistance spectrum to a set of Xoo strains,although plants carrying Xa3/Xa26-2 or Xa3/Xa26-3 showed lower resistance levels than the plants carrying Xa3/Xa26.These results suggest that the Xa3/Xa26 locus predates the speciation of A and C genome,which is approximately 7.5 million years ago.Thus,the resistance specificity of this locus has been conserved for a long time.

Locus of control and obesity.

Science.gov (United States)

Neymotin, Florence; Nemzer, Louis R

2014-01-01

In the developed world, the hazards associated with obesity have largely outstripped the risk of starvation. Obesity remains a difficult public health issue to address, due in large part to the many disciplines involved. A full understanding requires knowledge in the fields of genetics, endocrinology, psychology, sociology, economics, and public policy - among others. In this short review, which serves as an introduction to the Frontiers in Endocrinology research topic, we address one cross-disciplinary relationship: the interaction between the hunger/satiation neural circuitry, an individual's perceived locus of control, and the risk for obesity. Mammals have evolved a complex system for modulating energy intake. Overlaid on this, in humans, there exists a wide variation in "perceived locus of control" - that is, the extent to which an individual believes to be in charge of the events that affect them. Whether one has primarily an internal or external locus of control itself affects, and is affected by, external and physiological factors and has been correlated with the risk for obesity. Thus, the path from hunger and satiation to an individual's actual behavior may often be moderated by psychological factors, included among which is locus of control.

Precise Correction of Disease Mutations in Induced Pluripotent Stem Cells Derived From Patients With Limb Girdle Muscular Dystrophy.

Science.gov (United States)

Turan, Soeren; Farruggio, Alfonso P; Srifa, Waracharee; Day, John W; Calos, Michele P

2016-04-01

Limb girdle muscular dystrophies types 2B (LGMD2B) and 2D (LGMD2D) are degenerative muscle diseases caused by mutations in the dysferlin and alpha-sarcoglycan genes, respectively. Using patient-derived induced pluripotent stem cells (iPSC), we corrected the dysferlin nonsense mutation c.5713C>T; p.R1905X and the most common alpha-sarcoglycan mutation, missense c.229C>T; p.R77C, by single-stranded oligonucleotide-mediated gene editing, using the CRISPR/Cas9 gene-editing system to enhance the frequency of homology-directed repair. We demonstrated seamless, allele-specific correction at efficiencies of 0.7-1.5%. As an alternative, we also carried out precise gene addition strategies for correction of the LGMD2B iPSC by integration of wild-type dysferlin cDNA into the H11 safe harbor locus on chromosome 22, using dual integrase cassette exchange (DICE) or TALEN-assisted homologous recombination for insertion precise (THRIP). These methods employed TALENs and homologous recombination, and DICE also utilized site-specific recombinases. With DICE and THRIP, we obtained targeting efficiencies after selection of ~20%. We purified iPSC corrected by all methods and verified rescue of appropriate levels of dysferlin and alpha-sarcoglycan protein expression and correct localization, as shown by immunoblot and immunocytochemistry. In summary, we demonstrate for the first time precise correction of LGMD iPSC and validation of expression, opening the possibility of cell therapy utilizing these corrected iPSC.

Detection of maternal DNA in placental/umbilical cord blood by locus-specific amplification of the noninherited maternal HLA gene.

Science.gov (United States)

Scaradavou, A; Carrier, C; Mollen, N; Stevens, C; Rubinstein, P

1996-08-15

A critical issue regarding the broader utilization of placental/ umbilical cord blood (PCB) in unrelated bone marrow restoration is the possibility of contamination with maternal lymphocytes capable of immunological reactivity against the eventual recipient. On transplantation, such maternal cells might lead to graft-versus-host disease (GVHD) even if the intended donor's neonatal lymphocytes were unresponsive. We measured the proportion of PCB samples that were contaminated with maternal cells. Placental-maternal sample pairs were selected so that the mother was heterozygous for the DR53 haplotype, whereas the placental sample was DR53-negative. The PCB samples were investigated for the presence of the noninherited maternal gene DRB4, exclusive to the DR53 haplotypes. Locus-specific polymerase chain reaction amplification with DRB4 sequence-specific primers was followed by either gel electrophoresis or blotting and hybridization to an internal sequence DRB4 probe. Polymerase chain reaction products from DNA mixtures containing as low as 0.5 ng of a DRB4-positive DNA control in 1.0 microgram of a DRB4-negative DNA sample (1:2 x 10(3) dilution) showed a visible DRB4 band in agarose gels stained with ethidium bromide. Locus-specific hybridization increased the detection sensitivity to 1:10(5) (0.01 ng of the DRB4-positive DNA control). Control mixtures of known amounts of DRB4-positive and -negative DNA were included in all experiments. Comparison of the thickness of DRB4 bands after electrophoresis and the intensity of the DRB4-specific hybridization signals to the concentration controls allowed a rough estimation of the amount of maternal DNA in the placental blood specimens. A total of 213 PCB samples were tested. By gel electrophoresis, DRB4-specific bands were observed to be as strong or stronger in 23 (10.8%) samples as those in the 1:2 x 10(3) control, and 153 (17.8%) samples were negative in this test. The remaining 37 (17.3%) samples disclosed weaker DRB4

Mapping recessive ophthalmic diseases: linkage of the locus for Usher syndrome type II to a DNA marker on chromosome 1q.

Science.gov (United States)

Lewis, R A; Otterud, B; Stauffer, D; Lalouel, J M; Leppert, M

1990-06-01

Usher syndrome is a heterogeneous group of autosomal recessive disorders that combines variably severe congenital neurosensory hearing impairment with progressive night-blindness and visual loss similar to that in retinitis pigmentosa. Usher syndrome type I is distinguished by profound congenital (preverbal) deafness and retinal disease with onset in the first decade of life. Usher syndrome type II is characterized by partial hearing impairment and retinal dystrophy that occurs in late adolescence or early adulthood. The chromosomal assignment and the regional localization of the genetic mutation(s) causing the Usher syndromes are unknown. We analyzed a panel of polymorphic genomic markers for linkage to the disease gene among six families with Usher syndrome type I and 22 families with Usher syndrome type II. Significant linkage was established between Usher syndrome type II and the DNA marker locus THH33 (D1S81), which maps to chromosome 1q. The most likely location of the disease gene is at a map distance of 9 cM from THH33 (lod score 6.5). The same marker failed to show linkage in families segregating an allele for Usher syndrome type I. These data confirm the provisional assignment of the locus for Usher syndrome type II to the distal end of chromosome 1q and demonstrate that the clinical heterogeneity between Usher types I and II is caused by mutational events at different genetic loci. Regional localization has the potential to improve carrier detection and to provide antenatal diagnosis in families at risk for the disease.

Exclusion of the GNAS locus in PHP-Ib patients with broad GNAS methylation changes: evidence for an autosomal recessive form of PHP-Ib?

Science.gov (United States)

Fernández-Rebollo, Eduardo; Pérez de Nanclares, Guiomar; Lecumberri, Beatriz; Turan, Serap; Anda, Emma; Pérez-Nanclares, Gustavo; Feig, Denice; Nik-Zainal, Serena; Bastepe, Murat; Jüppner, Harald

2011-08-01

Most patients with autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP-Ib) carry maternally inherited microdeletions upstream of GNAS that are associated with loss of methylation restricted to GNAS exon A/B. Only few AD-PHP-Ib patients carry microdeletions within GNAS that are associated with loss of all maternal methylation imprints. These epigenetic changes are often indistinguishable from those observed in patients affected by an apparently sporadic PHP-Ib form that has not yet been defined genetically. We have now investigated six female patients affected by PHP-Ib (four unrelated and two sisters) with complete or almost complete loss of GNAS methylation, whose healthy children (11 in total) showed no epigenetic changes at this locus. Analysis of several microsatellite markers throughout the 20q13 region made it unlikely that PHP-Ib is caused in these patients by large deletions involving GNAS or by paternal uniparental isodisomy or heterodisomy of chromosome 20 (patUPD20). Microsatellite and single-nucleotide variation (SNV) data revealed that the two affected sisters share their maternally inherited GNAS alleles with unaffected relatives that lack evidence for abnormal GNAS methylation, thus excluding linkage to this locus. Consistent with these findings, healthy children of two unrelated sporadic PHP-Ib patients had inherited different maternal GNAS alleles, also arguing against linkage to this locus. Based on our data, it appears plausible that some forms of PHP-Ib are caused by homozygous or compound heterozygous mutation(s) in an unknown gene involved in establishing or maintaining GNAS methylation. Copyright © 2011 American Society for Bone and Mineral Research.

Escala de Locus de controle ELCO/TELEBRÁS Scale of Locus of control - ELCO

Directory of Open Access Journals (Sweden)

Luiz Pasquali

1998-01-01

Full Text Available Com base na teoria de Rotter e Escala de Levenson foi elaborada uma escala de Locus de Controle Organizacional (ELCO, composta por 28 itens. A escala foi validada com uma amostra de 350 empregados do Sistema Telebrás. Verificou-se a presença dos 2 fatores previstos na teoria, a saber: internalidade e externalidade, aparecendo a escala de externalidade, com 18 itens, bem estruturada (alfa = 0.81 e a de internalidade, com 10 itens, deixando a desejar no que se refere à consistência interna (alfa = 0.66. Com os dados desta pesquisa foi feita também análise do Locus de Controle desses mesmos empregados. A constatação mais saliente foi a de que o nível de internalidade caiu com o aumento do nível escolar e o aumento da experiência profissional desses mesmos empregados. Estes resultados surpreendentes foram interpretados em termos da situação típica da empresa, que está passando por um período de transição, a saber: a passagem da condição de empresa estatal para empresa privada, o que seria motivo da perda de confiança dos empregados na própria competência, particularmente por parte daqueles com maior competência intelectual e maior experiência profissional. Fez-se igualmente reparos na qualidade psicométrica da escala e da própria teoria do Locus de controle, no sentido de que esta precisa ser melhor axiomatizada para possibilitar a elaboração de escalas mais precisas para a medida dos construtos que propõe.A scale with 28 items, the Organizational Locus of Control (ELCO, was built based on Rotter’s theory and Levenson’s scale. ELCO was validated on a sample of 350 employees of Telebrás, a governmental firm in Brazil. As foreseen from the theory, a principal-axis factoring showed the presence of the expected two factors, namely internal and external locus of control. The external locus of control factor, composed of 18 items, showed good internal consistency (alpha =.81 whereas the internal factor, with 10 items

Mutational Analysis of Oculocutaneous Albinism: A Compact Review

Science.gov (United States)

Kamaraj, Balu

2014-01-01

Oculocutaneous albinism (OCA) is an autosomal recessive disorder caused by either complete lack of or a reduction of melanin biosynthesis in the melanocytes. The OCA1A is the most severe type with a complete lack of melanin production throughout life, while the milder forms OCA1B, OCA2, OCA3, and OCA4 show some pigment accumulation over time. Mutations in TYR, OCA2, TYRP1, and SLC45A2 are mainly responsible for causing oculocutaneous albinism. Recently, two new genes SLC24A5 and C10orf11 are identified that are responsible to cause OCA6 and OCA7, respectively. Also a locus has been mapped to the human chromosome 4q24 region which is responsible for genetic cause of OCA5. In this paper, we summarized the clinical and molecular features of OCA genes. Further, we reviewed the screening of pathological mutations of OCA genes and its molecular mechanism of the protein upon mutation by in silico approach. We also reviewed TYR (T373K, N371Y, M370T, and P313R), OCA2 (R305W), TYRP1 (R326H and R356Q) mutations and their structural consequences at molecular level. It is observed that the pathological genetic mutations and their structural and functional significance of OCA genes will aid in development of personalized medicine for albinism patients. PMID:25093188

The actin regulator coronin-1A is mutated in a thymic egress deficient mouse strain and in a T?B+NK+ SCID patient

OpenAIRE

Shiow, Lawrence R.; Roadcap, David W.; Paris, Kenneth; Watson, Susan R.; Grigorova, Irina L.; Lebet, Tonya; An, Jinping; Xu, Ying; Jenne, Craig N.; F?ger, Niko; Sorensen, Ricardo U.; Goodnow, Christopher C.; Bear, James E.; Puck, Jennifer M.; Cyster, Jason G.

2008-01-01

Mice carrying the recessive peripheral T cell deficiency (Ptcd) locus have a block in thymic egress but the mechanism responsible is undefined. Here we found that Ptcd T cells have an intrinsic migration defect, impaired lymphoid tissue trafficking and irregularly shaped protrusions. Characterization of the Ptcd locus revealed an E26K point mutation within the actin regulator coronin-1A (Coro1a) that enhanced its inhibition of the actin regulator Arp2/3 and resulted in its mislocalization fro...

Mutational spectrum in a worldwide study of 29,700 families with BRCA1 or BRCA2 mutations.

Science.gov (United States)

Rebbeck, Timothy R; Friebel, Tara M; Friedman, Eitan; Hamann, Ute; Huo, Dezheng; Kwong, Ava; Olah, Edith; Olopade, Olufunmilayo I; Solano, Angela R; Teo, Soo-Hwang; Thomassen, Mads; Weitzel, Jeffrey N; Chan, T L; Couch, Fergus J; Goldgar, David E; Kruse, Torben A; Palmero, Edenir Inêz; Park, Sue Kyung; Torres, Diana; van Rensburg, Elizabeth J; McGuffog, Lesley; Parsons, Michael T; Leslie, Goska; Aalfs, Cora M; Abugattas, Julio; Adlard, Julian; Agata, Simona; Aittomäki, Kristiina; Andrews, Lesley; Andrulis, Irene L; Arason, Adalgeir; Arnold, Norbert; Arun, Banu K; Asseryanis, Ella; Auerbach, Leo; Azzollini, Jacopo; Balmaña, Judith; Barile, Monica; Barkardottir, Rosa B; Barrowdale, Daniel; Benitez, Javier; Berger, Andreas; Berger, Raanan; Blanco, Amie M; Blazer, Kathleen R; Blok, Marinus J; Bonadona, Valérie; Bonanni, Bernardo; Bradbury, Angela R; Brewer, Carole; Buecher, Bruno; Buys, Saundra S; Caldes, Trinidad; Caliebe, Almuth; Caligo, Maria A; Campbell, Ian; Caputo, Sandrine M; Chiquette, Jocelyne; Chung, Wendy K; Claes, Kathleen B M; Collée, J Margriet; Cook, Jackie; Davidson, Rosemarie; de la Hoya, Miguel; De Leeneer, Kim; de Pauw, Antoine; Delnatte, Capucine; Diez, Orland; Ding, Yuan Chun; Ditsch, Nina; Domchek, Susan M; Dorfling, Cecilia M; Velazquez, Carolina; Dworniczak, Bernd; Eason, Jacqueline; Easton, Douglas F; Eeles, Ros; Ehrencrona, Hans; Ejlertsen, Bent; Engel, Christoph; Engert, Stefanie; Evans, D Gareth; Faivre, Laurence; Feliubadaló, Lidia; Ferrer, Sandra Fert; Foretova, Lenka; Fowler, Jeffrey; Frost, Debra; Galvão, Henrique C R; Ganz, Patricia A; Garber, Judy; Gauthier-Villars, Marion; Gehrig, Andrea; Gerdes, Anne-Marie; Gesta, Paul; Giannini, Giuseppe; Giraud, Sophie; Glendon, Gord; Godwin, Andrew K; Greene, Mark H; Gronwald, Jacek; Gutierrez-Barrera, Angelica; Hahnen, Eric; Hauke, Jan; Henderson, Alex; Hentschel, Julia; Hogervorst, Frans B L; Honisch, Ellen; Imyanitov, Evgeny N; Isaacs, Claudine; Izatt, Louise; Izquierdo, Angel; Jakubowska, Anna; James, Paul; Janavicius, Ramunas; Jensen, Uffe Birk; John, Esther M; Vijai, Joseph; Kaczmarek, Katarzyna; Karlan, Beth Y; Kast, Karin; Investigators, KConFab; Kim, Sung-Won; Konstantopoulou, Irene; Korach, Jacob; Laitman, Yael; Lasa, Adriana; Lasset, Christine; Lázaro, Conxi; Lee, Annette; Lee, Min Hyuk; Lester, Jenny; Lesueur, Fabienne; Liljegren, Annelie; Lindor, Noralane M; Longy, Michel; Loud, Jennifer T; Lu, Karen H; Lubinski, Jan; Machackova, Eva; Manoukian, Siranoush; Mari, Véronique; Martínez-Bouzas, Cristina; Matrai, Zoltan; Mebirouk, Noura; Meijers-Heijboer, Hanne E J; Meindl, Alfons; Mensenkamp, Arjen R; Mickys, Ugnius; Miller, Austin; Montagna, Marco; Moysich, Kirsten B; Mulligan, Anna Marie; Musinsky, Jacob; Neuhausen, Susan L; Nevanlinna, Heli; Ngeow, Joanne; Nguyen, Huu Phuc; Niederacher, Dieter; Nielsen, Henriette Roed; Nielsen, Finn Cilius; Nussbaum, Robert L; Offit, Kenneth; Öfverholm, Anna; Ong, Kai-Ren; Osorio, Ana; Papi, Laura; Papp, Janos; Pasini, Barbara; Pedersen, Inge Sokilde; Peixoto, Ana; Peruga, Nina; Peterlongo, Paolo; Pohl, Esther; Pradhan, Nisha; Prajzendanc, Karolina; Prieur, Fabienne; Pujol, Pascal; Radice, Paolo; Ramus, Susan J; Rantala, Johanna; Rashid, Muhammad Usman; Rhiem, Kerstin; Robson, Mark; Rodriguez, Gustavo C; Rogers, Mark T; Rudaitis, Vilius; Schmidt, Ane Y; Schmutzler, Rita Katharina; Senter, Leigha; Shah, Payal D; Sharma, Priyanka; Side, Lucy E; Simard, Jacques; Singer, Christian F; Skytte, Anne-Bine; Slavin, Thomas P; Snape, Katie; Sobol, Hagay; Southey, Melissa; Steele, Linda; Steinemann, Doris; Sukiennicki, Grzegorz; Sutter, Christian; Szabo, Csilla I; Tan, Yen Y; Teixeira, Manuel R; Terry, Mary Beth; Teulé, Alex; Thomas, Abigail; Thull, Darcy L; Tischkowitz, Marc; Tognazzo, Silvia; Toland, Amanda Ewart; Topka, Sabine; Trainer, Alison H; Tung, Nadine; van Asperen, Christi J; van der Hout, Annemieke H; van der Kolk, Lizet E; van der Luijt, Rob B; Van Heetvelde, Mattias; Varesco, Liliana; Varon-Mateeva, Raymonda; Vega, Ana; Villarreal-Garza, Cynthia; von Wachenfeldt, Anna; Walker, Lisa; Wang-Gohrke, Shan; Wappenschmidt, Barbara; Weber, Bernhard H F; Yannoukakos, Drakoulis; Yoon, Sook-Yee; Zanzottera, Cristina; Zidan, Jamal; Zorn, Kristin K; Hutten Selkirk, Christina G; Hulick, Peter J; Chenevix-Trench, Georgia; Spurdle, Amanda B; Antoniou, Antonis C; Nathanson, Katherine L

2018-05-01

The prevalence and spectrum of germline mutations in BRCA1 and BRCA2 have been reported in single populations, with the majority of reports focused on White in Europe and North America. The Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) has assembled data on 18,435 families with BRCA1 mutations and 11,351 families with BRCA2 mutations ascertained from 69 centers in 49 countries on six continents. This study comprehensively describes the characteristics of the 1,650 unique BRCA1 and 1,731 unique BRCA2 deleterious (disease-associated) mutations identified in the CIMBA database. We observed substantial variation in mutation type and frequency by geographical region and race/ethnicity. In addition to known founder mutations, mutations of relatively high frequency were identified in specific racial/ethnic or geographic groups that may reflect founder mutations and which could be used in targeted (panel) first pass genotyping for specific populations. Knowledge of the population-specific mutational spectrum in BRCA1 and BRCA2 could inform efficient strategies for genetic testing and may justify a more broad-based oncogenetic testing in some populations. © 2018 Wiley Periodicals, Inc.

Genetic analysis of a four generation Indian family with Usher syndrome: a novel insertion mutation in MYO7A.

Science.gov (United States)

Kumar, Arun; Babu, Mohan; Kimberling, William J; Venkatesh, Conjeevaram P

2004-11-24

Usher syndrome (USH) is a rare autosomal recessive disorder characterized by deafness and retinitis pigmentosa. The purpose of this study was to determine the genetic cause of USH in a four generation Indian family. Peripheral blood samples were collected from individuals for genomic DNA isolation. To determine the linkage of this family to known USH loci, microsatellite markers were selected from the candidate regions of known loci and used to genotype the family. Exon specific intronic primers for the MYO7A gene were used to amplify DNA samples from one affected individual from the family. PCR products were subsequently sequenced to detect mutation. PCR-SSCP analysis was used to determine if the mutation segregated with the disease in the family and was not present in 50 control individuals. All affected individuals had a classic USH type I (USH1) phenotype which included deafness, vestibular dysfunction and retinitis pigmentosa. Pedigree analysis suggested an autosomal recessive mode of inheritance of USH in the family. Haplotype analysis suggested linkage of this family to the USH1B locus on chromosome 11q. DNA sequence analysis of the entire coding region of the MYO7A gene showed a novel insertion mutation c.2663_2664insA in a homozygous state in all affected individuals, resulting in truncation of MYO7A protein. This is the first study from India which reports a novel MYO7A insertion mutation in a four generation USH family. The mutation is predicted to produce a truncated MYO7A protein. With the novel mutation reported here, the total number of USH causing mutations in the MYO7A gene described to date reaches to 75.

Mutational pattern of the nurse shark antigen receptor gene (NAR) is similar to that of mammalian Ig genes and to spontaneous mutations in evolution: the translesion synthesis model of somatic hypermutation.

Science.gov (United States)

Diaz, M; Velez, J; Singh, M; Cerny, J; Flajnik, M F

1999-05-01

The pattern of somatic mutations of shark and frog Ig is distinct from somatic hypermutation of Ig in mammals in that there is a bias to mutate GC base pairs and a low frequency of mutations. Previous analysis of the new antigen receptor gene in nurse sharks (NAR), however, revealed no bias to mutate GC base pairs and the frequency of mutation was comparable to that of mammalian IgG. Here, we analyzed 1023 mutations in NAR and found no targeting of the mechanism to any particular nucleotide but did obtain strong evidence for a transition bias and for strand polarity. As seen for all species studied to date, the serine codon AGC/T in NAR was a mutational hotspot. The NAR mutational pattern is most similar to that of mammalian IgG and furthermore both are strikingly akin to mutations acquired during the neutral evolution of nuclear pseudogenes, suggesting that a similar mechanism is at work for both processes. In yeast, most spontaneous mutations are introduced by the translesion synthesis DNA polymerase zeta (REV3) and in various DNA repair-deficient backgrounds transitions were more often REV3-dependent than were transversions. Therefore, we propose a model of somatic hypermutation where DNA polymerase zeta is recruited to the Ig locus. An excess of DNA glycosylases in germinal center reactions may further enhance the mutation frequency by a REV3-dependent mutagenic process known as imbalanced base excision repair.

Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

DEFF Research Database (Denmark)

Lawrenson, Kate; Kar, Siddhartha; McCue, Karen

2016-01-01

A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10(-20)), ER......'-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk....

RBE-LET relationships of high-LET radiations in drosophila mutations

International Nuclear Information System (INIS)

Yoshikawa, Isao; Takatsuji, Toshihiro; Nagano, Masaaki; Takada, Jun; Endo, Satoru; Hoshi, Masaharu

1999-01-01

The relative biological effectiveness (RBE) of 252 Cf neutrons and synchrotron-generated high-energy charged particles for mutation induction was evaluated as a function of linear energy transfer (LET), using the loss of heterozygosity for wing-hair mutations and the reversion of the mutant white-ivory eye-color in Drosophila melanogaster. Loss of heterozygosity for wing-hair mutations results predominantly from mitotic crossing over induced in wing anlage cells of larvae, while the reverse mutation of eye-color is due to an intragenic structural change (2.96 kb-DNA excision) in the white locus on the X-chromosome. The measurements were performed in a combined mutation assay system so that induced mutant wing-hair clones as well as revertant eye-color clone can be detected simultaneously in the same individual. Larvae were irradiated at the age of 3 days post oviposition with 252 Cf neutrons, carbon beam or neon beam. For the neutron irradiation, the RBE values for wing-hair mutations were larger than that for eye-color mutation by about 7 fold. The RBE of carbon ions for producing the wing-hair mutations increased with increase in LET. The estimated RBE values were found to be in the range 2 to 6.5 for the wing-hair. For neon beam irradiation, the RBE values for wing-hair mutations peak near 150 keV/μm and decrease with further increase in LET. On the other hand, the RBE values for the induction of the eye-color mutation are nearly unity in 252 Cf neutrons and both ions throughout the LET range irradiated. We discuss the relationships between the initial DNA damage and LET in considering the mechanism of somatic mutation induction. (author)

Identification of a novel mutation in WFS1 in a family affected by low-frequency hearing impairment

Energy Technology Data Exchange (ETDEWEB)

Kunz, Juergen; Marquez-Klaka, Ben; Uebe, Steffen; Volz-Peters, Anja; Berger, Roswitha; Rausch, Peter

2003-04-09

Previously we confirmed linkage of autosomal dominantly inherited low-frequency sensorineural hearing impairment (LFSNHI) in a German family to the genetic locus DFNA6/DFNA14 on chromosome 4p16.3 close to the markers D4S432 and D4S431. Analysis of data from the Human Genome Project, showed that WFS1 is located in this region. Mutations in WFS1 are known to be responsible for Wolfram syndrome (DIDMOAD, MIM no. 606201), which follows an autosomal recessive trait. Studies in low-frequency hearing loss families showed that mutations in WFS1 were responsible for the phenotype. In all affected family members analysed, we detected a missense mutation in WFS1 (K705N) and therefore confirm the finding that the majority of mutations responsible for LFSNHI are missense mutations which localise to the C-terminal domain of the protein.

Identification of a novel mutation in WFS1 in a family affected by low-frequency hearing impairment

International Nuclear Information System (INIS)

Kunz, Juergen; Marquez-Klaka, Ben; Uebe, Steffen; Volz-Peters, Anja; Berger, Roswitha; Rausch, Peter

2003-01-01

Previously we confirmed linkage of autosomal dominantly inherited low-frequency sensorineural hearing impairment (LFSNHI) in a German family to the genetic locus DFNA6/DFNA14 on chromosome 4p16.3 close to the markers D4S432 and D4S431. Analysis of data from the Human Genome Project, showed that WFS1 is located in this region. Mutations in WFS1 are known to be responsible for Wolfram syndrome (DIDMOAD, MIM no. 606201), which follows an autosomal recessive trait. Studies in low-frequency hearing loss families showed that mutations in WFS1 were responsible for the phenotype. In all affected family members analysed, we detected a missense mutation in WFS1 (K705N) and therefore confirm the finding that the majority of mutations responsible for LFSNHI are missense mutations which localise to the C-terminal domain of the protein

Impact of variation at the FTO locus on milk fat yield in Holstein dairy cattle.

Science.gov (United States)

Zielke, Lea G; Bortfeldt, Ralf H; Reissmann, Monika; Tetens, Jens; Thaller, Georg; Brockmann, Gudrun A

2013-01-01

This study explores the biological role of the Fat Mass and Obesity associated (FTO) gene locus on milk composition in German Holstein cattle. Since FTO controls energy homeostasis and expenditure and the FTO locus has repeatedly shown association with obesity in human studies, we tested FTO as a candidate gene in particular for milk fat yield, which represents a high amount of energy secreted during lactation. The study was performed on 2,402 bulls and 860 cows where dense milk composition data were available. Genetic information was taken from a 2 Mb region around FTO. Five SNPs and two haplotype blocks in a 725 kb region covering FTO and the neighboring genes RPGRIP1L, U6ATAC, and 5 S rRNA were associated with milk fat yield and also affected protein yield in the same direction. Interestingly, higher frequency SNP alleles and haplotypes within the FTO gene increased milk fat and protein yields by up to 2.8 and 2.2 kg per lactation, respectively, while the most frequent haplotype in the upstream block covering exon 1 of FTO to exon 15 of RPGRIP1L had opposite effects with lower fat and milk yield. Both haplotype blocks were also significant in cows. The loci accounted for about 1% of the corresponding trait variance in the population. The association signals not only provided evidence for at least two causative mutations in the FTO locus with a functional effect on milk but also milk protein yield. The pleiotropic effects suggest a biological function on the usage of energy resources and the control of energy balance rather than directly affecting fat and protein synthesis. The identified effect of the obesity gene locus on milk energy content suggests an impact on infant nutrition by breast feeding in humans.

Impact of variation at the FTO locus on milk fat yield in Holstein dairy cattle.

Directory of Open Access Journals (Sweden)

Lea G Zielke

Full Text Available This study explores the biological role of the Fat Mass and Obesity associated (FTO gene locus on milk composition in German Holstein cattle. Since FTO controls energy homeostasis and expenditure and the FTO locus has repeatedly shown association with obesity in human studies, we tested FTO as a candidate gene in particular for milk fat yield, which represents a high amount of energy secreted during lactation. The study was performed on 2,402 bulls and 860 cows where dense milk composition data were available. Genetic information was taken from a 2 Mb region around FTO. Five SNPs and two haplotype blocks in a 725 kb region covering FTO and the neighboring genes RPGRIP1L, U6ATAC, and 5 S rRNA were associated with milk fat yield and also affected protein yield in the same direction. Interestingly, higher frequency SNP alleles and haplotypes within the FTO gene increased milk fat and protein yields by up to 2.8 and 2.2 kg per lactation, respectively, while the most frequent haplotype in the upstream block covering exon 1 of FTO to exon 15 of RPGRIP1L had opposite effects with lower fat and milk yield. Both haplotype blocks were also significant in cows. The loci accounted for about 1% of the corresponding trait variance in the population. The association signals not only provided evidence for at least two causative mutations in the FTO locus with a functional effect on milk but also milk protein yield. The pleiotropic effects suggest a biological function on the usage of energy resources and the control of energy balance rather than directly affecting fat and protein synthesis. The identified effect of the obesity gene locus on milk energy content suggests an impact on infant nutrition by breast feeding in humans.

Two-step activation of meiosis by the mat1 locus in Schizosaccharomyces pombe

DEFF Research Database (Denmark)

Willer, M; Hoffmann, Ulla-Lisbeth; Styrkársdóttir, U

1995-01-01

of meiosis is based largely on indirect observations, and a more precise investigation of these events was required to define the interaction between the mat1 genes. Here we resolve this issue using synthetic pheromones and P/M strains with mutations in either mat1-Pc or mat1-Mc. Our results suggest a model...... in which the mat1 locus plays two roles in controlling meiosis. In the first instance, the mat1-Pc and mat1-Mc functions are required to produce the mating pheromones and receptors that allow the generation of a pheromone signal. This signal is required to induce the expression of mat1-Pm and mat1-Mm...

Cytogenetic mapping of a novel locus for type II Waardenburg syndrome.

Science.gov (United States)

Selicorni, Angelo; Guerneri, Silvana; Ratti, Antonia; Pizzuti, Antonio

2002-01-01

An Italian family in which Waardenburg syndrome type II (WS2) segregates together with a der(8) chromosome from a (4p;8p) balanced translocation was studied. Cytogenetic analysis by painting and subtelomeric probe hybridization positioned the chromosome 8 breakpoint at p22-pter. Fluorescence in situ hybridization analysis with yeast artificial chromosomes from a contig spanning the 8p21-pter region refined the breakpoint in an interval of less than 170 kb between markers WI-3823 and D8S1819. The only cloned gene for WS2 is that for microphtalmia (MITF) on chromosome 3p. In this family, MITF mutations were excluded by sequencing the whole coding region. The 8p23 region may represent a third locus for WS2 (WS2C).

SSR allelic variation of rice variety Hangxiangnuo bred by space mutation

International Nuclear Information System (INIS)

Yang Tifeng; Liu Chuanguang; Pan Dajian; Fan Zhilan; Li Chen; Chen Jianyou; Liu Bin; Jiang Yijun; Gao Yun; Zhou Hanqin

2011-01-01

Hangxiangnuo, an indica fragrant glutinous rice mutant, was induced by space environment. Comparing with its wild type Nanfengnuo, the yield and blast resistance of Hangxiangnuo are improved significantly and the grain shape became slender and with fragrance. To understand the mechanisms of space mutation and identify the changes at molecular level associated with phenotypic variations, SSR allelic variation analysis were performed on Hangxiangnuo and Nanfengnuo in this study. The results showed that 45 loci were polymorphic among the 156 SSR loci tested throughout the genome, the frequency of variation was 28.85%. Among the polymorphic loci, 42 loci only showed variations in the molecular weight of the amplified bands, only on locus increased the number of amplification bands in Hangxiangnuo and two loci were differed by heterozygous loci (with two amplification bands at one locus) detected in Nanfengnuo and homozygous loci in Hangxiangnuo. It suggests that the change of some loci in mutants was due to the normal segregation and recombination of heterozygous loci of the wild type. The variation frequencies among different chromosomes were quite different, with the highest one at 50.00% detected on chromosomes 7, 8 and 12, and the lowest at 6.25% on chromosome 6. The polymorphic loci were clustered on chromosomes throughout the genome indicating that large DNA segments mutation is one of the major variation patterns induced by space environment. Some of reported QTLs involved in grain shape, yield, fragrance and blast resistance were found to be located exactly in the mutated regions. Therefore, further study is needed to confirm that these QTLs are responsible for the trait variations. (authors)

Self-Esteem, Locus of Control, and Student Achievement.

Science.gov (United States)

Sterbin, Allan; Rakow, Ernest

The direct effects of locus of control and self-esteem on standardized test scores were studied. The relationships among the standardized test scores and measures of locus of control and self-esteem for 12,260 students from the National Education Longitudinal Study 1994 database were examined, using the same definition of locus of control and…

Risk of venous thromboembolism and myocardial infarction associated with factor V Leiden and prothrombin mutations and blood type

DEFF Research Database (Denmark)

Sode, Birgitte F; Allin, Kristine H; Dahl, Morten

2013-01-01

ABO blood type locus has been reported to be an important genetic determinant of venous and arterial thrombosis in genome-wide association studies. We tested the hypothesis that ABO blood type alone and in combination with mutations in factor V Leiden R506Q and prothrombin G20210A is associated...

Detection of EGFR mutations in plasma and biopsies from non-small cell lung cancer patients by allele-specific PCR assays

DEFF Research Database (Denmark)

Weber, Britta; Meldgaard, Peter; Hager, Henrik

2014-01-01

samples with allele-specific PCR assays. METHODS: Pairs of the diagnostic biopsy and plasma obtained just prior to start of erlotinib treatment were collected from 199 patients with adenocarcinoma of non-small-cell lung cancer. DNA from both sample types was isolated and examined for the presence...... of mutations in exons 18-21 of the EGFR gene, employing the cobas(®) EGFR Tissue Test and cobas(®) EGFR Blood Test (in development, Roche Molecular Systems, Inc., CA, USA). RESULTS: Test results were obtained in all 199 (100%) plasma samples and 196/199 (98%) of the biopsies. EGFR-activating mutations were...... identified in 24/199 (12%) plasma samples and 28/196 (14%) biopsy samples, and 17/196 (9%) matched pairs contained the same mutation. Six EGFR mutations were present only in plasma samples but not in the biopsy samples. The overall concordance of the EGFR gene mutations detected in plasma and biopsy tissue...

VNTR internal structure mapping at the {alpha}-globin 3{prime}HVR locus reveals a hierachy of related lineages in oceania

Energy Technology Data Exchange (ETDEWEB)

Martinson, J.J.; Clegg, J.B.; Boyce, A.J. [Univ. of Oxford (United Kingdom)

1994-09-01

Analysis of the {alpha}-globin gene complex in Oceania has revealed many different rearrangements which remove one of the adult globin genes. Frequencies of these deletion chromosomes are elevated by malarial resistance conferred by the resulting {alpha}-thalassaemia. One particular deletion chromosome, designated -{alpha}{sup 3.7}III, is found at high levels in Melanesia and Polynesia: RFLP haplotype analysis shows that this deletion is always found on chromosomes bearing the IIIa haplotype and is likely to be the product of one single rearrangement event. A subset of the -{alpha}{sup 3.7}III chromosomes carries a more recent mutation which generates the haemoglobin variant HbJ{sup Tongariki}. We have characterized the allelic variation at the 3{prime}HVR VNTR locus located 6 kb from the globin genes in each of these groups of chromosomes. We have determined the internal structure of these alleles by RFLP mapping of PCR-amplified DNA: within each group, the allelic diversity results from the insertion and/or deletion of small {open_quotes}motifs{close_quotes} of up to 6 adjacent repeats. Mapping of 3{prime}HVR alleles associated with other haplotypes reveals that these are composed of repeat arrays that are substantially different to those derived from IIIa chromosomes, indicating that interchromosomal recombination between heterologous haplotypes does not account for any of the diversity seen to date. We have recently shown that allelic size variation at the two VNTR loci flanking the {alpha}-globin complex is very closely linked to the haplotypes known to be present at this locus. Here we show that, within a haplotype, VNTR alleles are very closely related to each other on the basis of internal structure and demonstrate that intrachromosomal mutation processes involving small numbers of tandem repeats are the main cause of variation at this locus.

Locus of Control and Obesity

Directory of Open Access Journals (Sweden)

Florence eNeymotin

2014-10-01

Full Text Available In the developed world, the hazards associated with obesity have largely outstripped the risk of starvation. Obesity remains a difficult public health issue to address, due in large part to the many disciplines involved. A full understanding requires knowledge in the fields of genetics, endocrinology, psychology, sociology, economics, and public policy – among others. In this short review, which serves as an introduction to the Frontiers in Endocrinology research topic, we address one cross-disciplinary relationship: the interaction between the hunger/satiation neural circuitry, an individual’s perceived locus of control, and the risk for obesity. Mammals have evolved a complex system for modulating energy intake. Overlaid on this, in humans, there exists a wide variation in perceived locus of control – that is, the extent to which an individual believes to be in charge of the events that affect them. Whether one has primarily an internal or external locus of control itself affects, and is affected by, external and physiological factors and has been correlated with the risk for obesity. Thus, the path from hunger and satiation to an individual’s actual behavior may often be moderated by psychological factors, included among which is locus of control.

Ancient roots for polymorphism at the HLA-DQ. alpha. locus in primates

Energy Technology Data Exchange (ETDEWEB)

Gyllensten, U.B.; Erlich, H.A. (Cetus Corp., Emeryville, CA (USA))

1989-12-01

The genes encoding the human histocompatibility antigens (HLA) exhibit a remarkable degree of polymorphism as revealed by immunologic and molecular analyses. This extensive sequence polymorphism either may have been generated during the lifetime of the human species or could have arisen before speciation and been maintained in the contemporary human population by selection or, possibly, by genetic drift. These two hypotheses were examined using the polymerase chain reaction method to amplify polymorphic sequences from the DQ{alpha} locus, as well as the DX{alpha} locus, an homologous but nonexpressed locus, in a series of primates that diverged at known times. In general, the amino acid sequence of a specific human DQ{alpha} allelic type is more closely related to its chimpanzee or gorilla counterpart than to other human DQ{alpha} alleles. Phylogenetic analysis of the silent nucleotide position changes shows that the similarity of allelic types between species is due to common ancestry rather than convergent evolution. Thus, most of the polymorphism at the DQ{alpha} locus in the human species was already present at least 5 million years ago in the ancestral species that gave rise to the chimpanzee, gorilla, and human lineages. However, one of the DQ{alpha} alleles may have arisen after speciation by recombination between two ancestral alleles.

Refinement of the NHS locus on chromosome Xp22.13 and analysis of five candidate genes.

Science.gov (United States)

Toutain, Annick; Dessay, Benoît; Ronce, Nathalie; Ferrante, Maria-Immacolata; Tranchemontagne, Julie; Newbury-Ecob, Ruth; Wallgren-Pettersson, Carina; Burn, John; Kaplan, Josseline; Rossi, Annick; Russo, Silvia; Walpole, Ian; Hartsfield, James K; Oyen, Nina; Nemeth, Andrea; Bitoun, Pierre; Trump, Dorothy; Moraine, Claude; Franco, Brunella

2002-09-01

Nance-Horan syndrome (NHS) is an X-linked condition characterised by congenital cataracts, dental abnormalities, dysmorphic features, and mental retardation in some cases. Previous studies have mapped the disease gene to a 2 cM interval on Xp22.2 between DXS43 and DXS999. We report additional linkage data resulting from the analysis of eleven independent NHS families. A maximum lod score of 9.94 (theta=0.00) was obtained at the RS1 locus and a recombination with locus DXS1195 on the telomeric side was observed in two families, thus refining the location of the gene to an interval of around 1 Mb on Xp22.13. Direct sequencing or SSCP analysis of the coding exons of five genes (SCML1, SCML2, STK9, RS1 and PPEF1), considered as candidate genes on the basis of their location in the critical interval, failed to detect any mutation in 12 unrelated NHS patients, thus making it highly unlikely that these genes are implicated in NHS.

Increased Ac excision (iae): Arabidopsis thaliana mutations affecting Ac transposition

International Nuclear Information System (INIS)

Jarvis, P.; Belzile, F.; Page, T.; Dean, C.

1997-01-01

The maize transposable element Ac is highly active in the heterologous hosts tobacco and tomato, but shows very much reduced levels of activity in Arabidopsis. A mutagenesis experiment was undertaken with the aim of identifying Arabidopsis host factors responsible for the observed low levels of Ac activity. Seed from a line carrying a single copy of the Ac element inserted into the streptomycin phosphotransferase (SPT) reporter fusion, and which displayed typically low levels of Ac activity, were mutagenized using gamma rays. Nineteen mutants displaying high levels of somatic Ac activity, as judged by their highly variegated phenotypes, were isolated after screening the M2 generation on streptomycin-containing medium. The mutations fall into two complementation groups, iae1 and iae2, are unlinked to the SPT::Ac locus and segregate in a Mendelian fashion. The iae1 mutation is recessive and the iae2 mutation is semi-dominant. The iae1 and iae2 mutants show 550- and 70-fold increases, respectively, in the average number of Ac excision sectors per cotyledon. The IAE1 locus maps to chromosome 2, whereas the SPT::Ac reporter maps to chromosome 3. A molecular study of Ac activity in the iae1 mutant confirmed the very high levels of Ac excision predicted using the phenotypic assay, but revealed only low levels of Ac re-insertion. Analyses of germinal transposition in the iae1 mutant demonstrated an average germinal excision frequency of 3% and a frequency of independent Ac re-insertions following germinal excision of 22%. The iae mutants represents a possible means of improving the efficiency of Ac/Ds transposon tagging systems in Arabidopsis, and will enable the dissection of host involvement in Ac transposition and the mechanisms employed for controlling transposable element activity

Relationships between locus of control and paranormal beliefs.

Science.gov (United States)

Newby, Robert W; Davis, Jessica Boyette

2004-06-01

The present study investigated the associations between scores on paranormal beliefs, locus of control, and certain psychological processes such as affect and cognitions as measured by the Linguistic Inquiry and Word Count. Analysis yielded significant correlations between scores on Locus of Control and two subscales of Tobacyk's (1988) Revised Paranormal Beliefs Scale, New Age Philosophy and Traditional Paranormal Beliefs. A step-wise multiple regression analysis indicated that Locus of Control was significantly related to New Age Philosophy. Other correlations were found between Tobacyk's subscales, Locus of Control, and three processes measured by the Linguistic Inquiry and Word Count.

In silico analysis of a disease-causing mutation in PCDH15 gene in a consanguineous Pakistani family with Usher phenotype

Directory of Open Access Journals (Sweden)

Shamim Saleha

2016-05-01

Full Text Available AIM: To map Usher phenotype in a consanguineous Pakistani family and identify disease-associated mutation in a causative gene to establish phenotype-genotype correlation. METHODS: A consanguineous Pakistani family in which Usher phenotype was segregating as an autosomal recessive trait was ascertained. On the basis of results of clinical investigations of affected members of this family disease was diagnosed as Usher syndrome (USH. To identify the locus responsible for the Usher phenotype in this family, genomic DNA from blood sample of each individual was genotyped using microsatellite Short Tandem Repeat (STR markers for the known Usher syndrome loci. Then direct sequencing was performed to find out disease associated mutations in the candidate gene. RESULTS: By genetic linkage analysis, the USH phenotype of this family was mapped to PCDH15 locus on chromosome 10q21.1. Three different point mutations in exon 11 of PCDH15 were identified and one of them, c.1304A>C was found to be segregating with the disease phenotype in Pakistani family with Usher phenotype. This, c.1304A>C transversion mutation predicts an amino-acid substitution of aspartic acid with an alanine at residue number 435 (p.D435A of its protein product. Moreover, in silico analysis revealed conservation of aspartic acid at position 435 and predicated this change as pathogenic. CONCLUSION: The identification of c.1304A>C pathogenic mutation in PCDH15 gene and its association with Usher syndrome in a consanguineous Pakistani family is the first example of a missense mutation of PCDH15 causing USH1 phenotype. In previous reports, it was hypothesized that severe mutations such as truncated protein of PCDH15 led to the Usher I phenotype and that missense variants are mainly responsible for non-syndromic hearing impairment.

In silico analysis of a disease-causing mutation in PCDH15 gene in a consanguineous Pakistani family with Usher phenotype.

Science.gov (United States)

Saleha, Shamim; Ajmal, Muhammad; Jamil, Muhammad; Nasir, Muhammad; Hameed, Abdul

2016-01-01

To map Usher phenotype in a consanguineous Pakistani family and identify disease-associated mutation in a causative gene to establish phenotype-genotype correlation. A consanguineous Pakistani family in which Usher phenotype was segregating as an autosomal recessive trait was ascertained. On the basis of results of clinical investigations of affected members of this family disease was diagnosed as Usher syndrome (USH). To identify the locus responsible for the Usher phenotype in this family, genomic DNA from blood sample of each individual was genotyped using microsatellite Short Tandem Repeat (STR) markers for the known Usher syndrome loci. Then direct sequencing was performed to find out disease associated mutations in the candidate gene. By genetic linkage analysis, the USH phenotype of this family was mapped to PCDH15 locus on chromosome 10q21.1. Three different point mutations in exon 11 of PCDH15 were identified and one of them, c.1304A>C was found to be segregating with the disease phenotype in Pakistani family with Usher phenotype. This, c.1304A>C transversion mutation predicts an amino-acid substitution of aspartic acid with an alanine at residue number 435 (p.D435A) of its protein product. Moreover, in silico analysis revealed conservation of aspartic acid at position 435 and predicated this change as pathogenic. The identification of c.1304A>C pathogenic mutation in PCDH15 gene and its association with Usher syndrome in a consanguineous Pakistani family is the first example of a missense mutation of PCDH15 causing USH1 phenotype. In previous reports, it was hypothesized that severe mutations such as truncated protein of PCDH15 led to the Usher I phenotype and that missense variants are mainly responsible for non-syndromic hearing impairment.

A splice donor mutation in NAA10 results in the dysregulation of the retinoic acid signaling pathway and causes Lenz microphthalmia syndrome

Science.gov (United States)

Esmailpour, Taraneh; Riazifar, Hamidreza; Liu, Linan; Donkervoort, Sandra; Huang, Vincent H; Madaan, Shreshtha; Shoucri, Bassem M; Busch, Anke; Wu, Jie; Towbin, Alexander; Chadwick, Robert B; Sequeira, Adolfo; Vawter, Marquis P; Sun, Guoli; Johnston, Jennifer J; Biesecker, Leslie G; Kawaguchi, Riki; Sun, Hui; Kimonis, Virginia; Huang, Taosheng

2014-01-01

Introduction Lenz microphthalmia syndrome (LMS) is a genetically heterogeneous X-linked disorder characterised by microphthalmia/anophthalmia, skeletal abnormalities, genitourinary malformations, and anomalies of the digits, ears, and teeth. Intellectual disability and seizure disorders are seen in about 60% of affected males. To date, no gene has been identified for LMS in the microphthalmia syndrome 1 locus (MCOPS1). In this study, we aim to find the disease-causing gene for this condition. Methods and results Using exome sequencing in a family with three affected brothers, we identified a mutation in the intron 7 splice donor site (c.471+2T→A) of the N-acetyltransferase NAA10 gene. NAA10 has been previously shown to be mutated in patients with Ogden syndrome, which is clinically distinct from LMS. Linkage studies for this family mapped the disease locus to Xq27-Xq28, which was consistent with the locus of NAA10. The mutation co-segregated with the phenotype and cDNA analysis showed aberrant transcripts. Patient fibroblasts lacked expression of full length NAA10 protein and displayed cell proliferation defects. Expression array studies showed significant dysregulation of genes associated with genetic forms of anophthalmia such as BMP4, STRA6, and downstream targets of BCOR and the canonical WNT pathway. In particular, STRA6 is a retinol binding protein receptor that mediates cellular uptake of retinol/vitamin A and plays a major role in regulating the retinoic acid signalling pathway. A retinol uptake assay showed that retinol uptake was decreased in patient cells. Conclusions We conclude that the NAA10 mutation is the cause of LMS in this family, likely through the dysregulation of the retinoic acid signalling pathway. PMID:24431331

Genetic association of multiple sclerosis with the marker rs391745 near the endogenous retroviral locus HERV-Fc1: analysis of disease subtypes

DEFF Research Database (Denmark)

Hansen, Bettina; Oturai, Annette Bang; Harbo, Hanne F

2011-01-01

We have previously described the occurrence of multiple sclerosis (MS) to be associated with human endogenous retroviruses, specifically the X-linked viral locus HERV-Fc1. The aim of this study was to investigate a possible association of the HERV-Fc1 locus with subtypes of MS. MS patients......-Fc1 locus (p = 0.003), while primary progressive disease was not. The ability to see genetic differences between subtypes of MS near this gene speaks for the involvement of the virus HERV-Fc1 locus in modifying the disease course of MS....

The spontaneous chlorophyll mutation frequency in barley

DEFF Research Database (Denmark)

Jørgensen, Jørgen Helms; Jensen, Hans Peter

1986-01-01

A total of 1866 barley plants were progeny tested in the greenhouse. Twenty-five plants segregated for newly arisen, spontaneous chlorophyll mutant genes. Among the total of 470,129 seedlings screened there were 79 mutants (1.7 .+-. 0.6 .times. 10-4). The data are added to data from three similar...... materials and the resulting estimate of the chlorophyll mutant frequency is 1.6 .times. 10-4 in about 1.43 million seedlings. The estimate of the chlorophyll mutation rate per generation is close to 67.3 .times. 10-4 per diploid genome or in the order of 6 .times. 10-7 per locus and haploid genome....

Specific UV-induced mutation spectrum in the p53 gene of skin tumors from DNA-repair-deficient xeroderma pigmentosum patients

International Nuclear Information System (INIS)

Dumaz, N.; Drougard, C.; Sarasin, A.; Daya-Grosjean, L.

1993-01-01

The UV component of sunlight is the major carcinogen involved in the etiology of skin cancers. The authors have studied the rare, hereditary syndrome xeroderma pigmentosum (XP), which is characterized by a very high incidence of cutaneous tumors on exposed skin at an early age, probably due to a deficiency in excision repair of UV-induced lesions. It is interesting to determine the UV mutation spectrum in XP skin tumors in order to correlate the absence of repair of specific DNA lesions and the initiation of skin tumors. The p53 gene is frequently mutated in human cancers and represents a good target for studying mutation spectra since there are >100 potential sites for phenotypic mutations. Using reverse transcription-PCR and single-strand conformation polymorphism to analyze >40 XP skin tumors (mainly basal and squamous cell carcinomas), the authors have found that 40% (17 out of 43) contained at least one point mutation on the p53 gene. All the mutations were located at dipyrimidine sites, essentially at CC sequences, which are hot spots for UV-induced DNA lesions. Sixty-one percent of these mutations were tandem CC → TT mutations considered to be unique to UV-induced lesions; these mutations are not observed in internal human tumors. All the mutations, except two, must be due to translesion synthesis of unrepaired dipyrimidine lesions left on the nontranscribed strand. These results show the existence of preferential repair of UV lesions [either pyrimidine dimers or pyrimidine-pyrimidone (6-4) photoproducts] on the transcribed strand in human tissues

Founder effect of a prevalent phenylketonuria mutation in the Oriental population

Energy Technology Data Exchange (ETDEWEB)

Wang, Tao (Baylor College of Medicine, Houston, TX (United States) Chinese Academy of Medical Sciences, Beijing (China)); Okano, Yoshiyuki; Eisensmith, R.C.; Harvey, M.L.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (United States)); Lo, W.H.Y.; Yuan, Lifang (Chinese Academy of Medical Sciences, Beijing (China)); Huang, Shuzhen; Zeng, Yitao (Shanghai Children' s Hospital (China)); Furuyama, Junichi (Hyogo College of Medicine, Nishinomiya (Japan)); Oura, Toshiaki (Osaka Municipal Rehabilitation Center for the Disabled, Osaka (Japan)); Sommer, S.S. (Mayo Clinic/Foundation, Rochester, MN (United States))

1991-03-15

A missense mutation has been identified in the human phenylalanine hydroxylase Chinese patient with classic phenylketonuria (PKU). A G-to-C transition at the second base of codon 413 in exon 12 of the gene results in the substitution of Pro{sup 413} for Arg{sup 413} in the mutant protein. This mutation (R413P) results in negligible enzymatic activity when expressed in heterologous mammalian cells and is compatible with a classic PKU phenotype in the patient. Population genetic studies reveal that this mutation is tightly linked to restriction fragment length polymorphism haplotype 4, which is the predominant haplotype of the PAH locus in the Oriental population. It accounts for 13.8% of northern Chinese and 27% of Japanese PKU alleles, but it is rare in southern Chinese (2.2%) and is absent in the Caucasian population. The data demonstrate unambiguously that the mutation occurred after racial divergence of Orientals and Caucasians and suggest that the allele has spread throughout the Orient by a founder effect. Previous protein polymorphism studies in eastern Asia have led to the hypothesis that northern Mongoloids represented a founding population in Asia. The results are compatible with this hypothesis in that the PKU mutation might have occurred in northern Mongoloids and subsequently spread to the Chinese and Japanese populations.

Founder effect of a prevalent phenylketonuria mutation in the Oriental population

International Nuclear Information System (INIS)

Wang, Tao; Okano, Yoshiyuki; Eisensmith, R.C.; Harvey, M.L.; Woo, S.L.C.; Lo, W.H.Y.; Yuan, Lifang; Huang, Shuzhen; Zeng, Yitao; Furuyama, Junichi; Oura, Toshiaki; Sommer, S.S.

1991-01-01

A missense mutation has been identified in the human phenylalanine hydroxylase Chinese patient with classic phenylketonuria (PKU). A G-to-C transition at the second base of codon 413 in exon 12 of the gene results in the substitution of Pro 413 for Arg 413 in the mutant protein. This mutation (R413P) results in negligible enzymatic activity when expressed in heterologous mammalian cells and is compatible with a classic PKU phenotype in the patient. Population genetic studies reveal that this mutation is tightly linked to restriction fragment length polymorphism haplotype 4, which is the predominant haplotype of the PAH locus in the Oriental population. It accounts for 13.8% of northern Chinese and 27% of Japanese PKU alleles, but it is rare in southern Chinese (2.2%) and is absent in the Caucasian population. The data demonstrate unambiguously that the mutation occurred after racial divergence of Orientals and Caucasians and suggest that the allele has spread throughout the Orient by a founder effect. Previous protein polymorphism studies in eastern Asia have led to the hypothesis that northern Mongoloids represented a founding population in Asia. The results are compatible with this hypothesis in that the PKU mutation might have occurred in northern Mongoloids and subsequently spread to the Chinese and Japanese populations

A retrospective study to rule out possible association of genetic and non-genetic risk factors with specific brca mutation positive breast cancers is some Pakistani females

International Nuclear Information System (INIS)

Malik, S.; Imran, M.; Hanif, A.; Bilal, M.

2009-01-01

Breast cancer is the most common malignancy among Asian women including Pakistan where recurrent mutations among certain sub-ethnic groups predisposing to breast cancer have recently been established. Study Design: The current retrospective study involves identification of genetic and non-genetic risk factors in 27 specific mutation positive females out of a. total of 100 females diagnosed with breast cancer, representing a sample from the Punjabi ethnic population of the city of Lahore. The study has been carried out by telephonic communication with the mutation positive patients or their relatives. Results: Out of the total 27% patients positive for specific BRCA mutations, 23% were positive for BRCAI mutations and 4% for BRCA2. Among a total of 100 breast cancer patients the BRCAI-IVS14, lG>A mutation was identified in 5 Punjabi ethnic females with Rajput sub ethnicity, BRCAI-3889delAG in 10 (8 with Mughal and 2 with Khan sub ethnicity), BRCAI-2080insA in 8 (Rajput sub ethnics) and BRCA2-3337C>T in 4 (Minhas sub ethnic) subjects. Two BRCAI mutations, namely 3889delAG and 2080insA were found to coexist in only one study case (with Mughal sub ethnicity). All the mutation positive breast cancers had unilateral ductal carcinoma. Of the 23 cases positive for screened BRCAI mutations, 17 were diagnosed for breast cancer at a relatively early age (age<40) and 6 were diagnosed at late age (age<41) whereas all cases positive for single BRCA2 mutation under consideration were diagnosed at late age. Furthermore, 24 of 27 patients with specific BRCA mutations had a positive family history of breast cancer. The high prevalence of the screened BRCA mutations in certain Punjabi sub-ethnicities indicates the importance of counseling. It is suggested that consanguinity may be a risk factor for recurrent population specific mutations. Hormonal factors including use of oral contraceptives, polycystic ovaries, central obesity, nulliparity, late age at first pregnancy, lack of

A mouse model of the human Fragile X syndrome I304N mutation.

Directory of Open Access Journals (Sweden)

Julie B Zang

2009-12-01

Full Text Available The mental retardation, autistic features, and behavioral abnormalities characteristic of the Fragile X mental retardation syndrome result from the loss of function of the RNA-binding protein FMRP. The disease is usually caused by a triplet repeat expansion in the 5'UTR of the FMR1 gene. This leads to loss of function through transcriptional gene silencing, pointing to a key function for FMRP, but precluding genetic identification of critical activities within the protein. Moreover, antisense transcripts (FMR4, ASFMR1 in the same locus have been reported to be silenced by the repeat expansion. Missense mutations offer one means of confirming a central role for FMRP in the disease, but to date, only a single such patient has been described. This patient harbors an isoleucine to asparagine mutation (I304N in the second FMRP KH-type RNA-binding domain, however, this single case report was complicated because the patient harbored a superimposed familial liver disease. To address these issues, we have generated a new Fragile X Syndrome mouse model in which the endogenous Fmr1 gene harbors the I304N mutation. These mice phenocopy the symptoms of Fragile X Syndrome in the existing Fmr1-null mouse, as assessed by testicular size, behavioral phenotyping, and electrophysiological assays of synaptic plasticity. I304N FMRP retains some functions, but has specifically lost RNA binding and polyribosome association; moreover, levels of the mutant protein are markedly reduced in the brain specifically at a time when synapses are forming postnatally. These data suggest that loss of FMRP function, particularly in KH2-mediated RNA binding and in synaptic plasticity, play critical roles in pathogenesis of the Fragile X Syndrome and establish a new model for studying the disorder.

IDH-mutant glioma specific association of rs55705857 located at 8q24.21 involves MYC deregulation

Science.gov (United States)

Oktay, Yavuz; Ülgen, Ege; Can, Özge; Akyerli, Cemaliye B.; Yüksel, Şirin; Erdemgil, Yiğit; Durası, İ. Melis; Henegariu, Octavian Ioan; Nanni, E. Paolo; Selevsek, Nathalie; Grossmann, Jonas; Erson-Omay, E. Zeynep; Bai, Hanwen; Gupta, Manu; Lee, William; Turcan, Şevin; Özpınar, Aysel; Huse, Jason T.; Sav, M. Aydın; Flanagan, Adrienne; Günel, Murat; Sezerman, O. Uğur; Yakıcıer, M. Cengiz; Pamir, M. Necmettin; Özduman, Koray

2016-01-01

The single nucleotide polymorphism rs55705857, located in a non-coding but evolutionarily conserved region at 8q24.21, is strongly associated with IDH-mutant glioma development and was suggested to be a causal variant. However, the molecular mechanism underlying this association has remained unknown. With a case control study in 285 gliomas, 316 healthy controls, 380 systemic cancers, 31 other CNS-tumors, and 120 IDH-mutant cartilaginous tumors, we identified that the association was specific to IDH-mutant gliomas. Odds-ratios were 9.25 (5.17–16.52; 95% CI) for IDH-mutated gliomas and 12.85 (5.94–27.83; 95% CI) for IDH-mutated, 1p/19q co-deleted gliomas. Decreasing strength with increasing anaplasia implied a modulatory effect. No somatic mutations were noted at this locus in 114 blood-tumor pairs, nor was there a copy number difference between risk-allele and only-ancestral allele carriers. CCDC26 RNA-expression was rare and not different between the two groups. There were only minor subtype-specific differences in common glioma driver genes. RNA sequencing and LC-MS/MS comparisons pointed to significantly altered MYC-signaling. Baseline enhancer activity of the conserved region specifically on the MYC promoter and its further positive modulation by the SNP risk-allele was shown in vitro. Our findings implicate MYC deregulation as the underlying cause of the observed association. PMID:27282637

A multiple genome analysis of Mycobacterium tuberculosis reveals specific novel genes and mutations associated with pyrazinamide resistance

KAUST Repository

Sheen, Patricia

2017-10-11

Tuberculosis (TB) is a major global health problem and drug resistance compromises the efforts to control this disease. Pyrazinamide (PZA) is an important drug used in both first and second line treatment regimes. However, its complete mechanism of action and resistance remains unclear.We genotyped and sequenced the complete genomes of 68 M. tuberculosis strains isolated from unrelated TB patients in Peru. No clustering pattern of the strains was verified based on spoligotyping. We analyzed the association between PZA resistance with non-synonymous mutations and specific genes. We found mutations in pncA and novel genes significantly associated with PZA resistance in strains without pncA mutations. These included genes related to transportation of metal ions, pH regulation and immune system evasion.These results suggest potential alternate mechanisms of PZA resistance that have not been found in other populations, supporting that the antibacterial activity of PZA may hit multiple targets.

A multiple genome analysis of Mycobacterium tuberculosis reveals specific novel genes and mutations associated with pyrazinamide resistance

KAUST Repository

Sheen, Patricia; Requena, David; Gushiken, Eduardo; Gilman, Robert H.; Antiparra, Ricardo; Lucero, Bryan; Lizá rraga, Pilar; Cieza, Basilio; Roncal, Elisa; Grandjean, Louis; Pain, Arnab; McNerney, Ruth; Clark, Taane G.; Moore, David; Zimic, Mirko

2017-01-01

Tuberculosis (TB) is a major global health problem and drug resistance compromises the efforts to control this disease. Pyrazinamide (PZA) is an important drug used in both first and second line treatment regimes. However, its complete mechanism of action and resistance remains unclear.We genotyped and sequenced the complete genomes of 68 M. tuberculosis strains isolated from unrelated TB patients in Peru. No clustering pattern of the strains was verified based on spoligotyping. We analyzed the association between PZA resistance with non-synonymous mutations and specific genes. We found mutations in pncA and novel genes significantly associated with PZA resistance in strains without pncA mutations. These included genes related to transportation of metal ions, pH regulation and immune system evasion.These results suggest potential alternate mechanisms of PZA resistance that have not been found in other populations, supporting that the antibacterial activity of PZA may hit multiple targets.

The industrial melanism mutation in British peppered moths is a transposable element.

Science.gov (United States)

Van't Hof, Arjen E; Campagne, Pascal; Rigden, Daniel J; Yung, Carl J; Lingley, Jessica; Quail, Michael A; Hall, Neil; Darby, Alistair C; Saccheri, Ilik J

2016-06-02

Discovering the mutational events that fuel adaptation to environmental change remains an important challenge for evolutionary biology. The classroom example of a visible evolutionary response is industrial melanism in the peppered moth (Biston betularia): the replacement, during the Industrial Revolution, of the common pale typica form by a previously unknown black (carbonaria) form, driven by the interaction between bird predation and coal pollution. The carbonaria locus has been coarsely localized to a 200-kilobase region, but the specific identity and nature of the sequence difference controlling the carbonaria-typica polymorphism, and the gene it influences, are unknown. Here we show that the mutation event giving rise to industrial melanism in Britain was the insertion of a large, tandemly repeated, transposable element into the first intron of the gene cortex. Statistical inference based on the distribution of recombined carbonaria haplotypes indicates that this transposition event occurred around 1819, consistent with the historical record. We have begun to dissect the mode of action of the carbonaria transposable element by showing that it increases the abundance of a cortex transcript, the protein product of which plays an important role in cell-cycle regulation, during early wing disc development. Our findings fill a substantial knowledge gap in the iconic example of microevolutionary change, adding a further layer of insight into the mechanism of adaptation in response to natural selection. The discovery that the mutation itself is a transposable element will stimulate further debate about the importance of 'jumping genes' as a source of major phenotypic novelty.

Predictive and prognostic value of preoperative serum tumor markers is EGFR mutation-specific in resectable non-small-cell lung cancer

Science.gov (United States)

Jiang, Richeng; Wang, Xinyue; Li, Kai

2016-01-01

Background The predictive and prognostic value of carcinoembryonic antigen (CEA), cytokeratin-19 fragments (Cyfra21-1), squamous cell carcinoma antigen (SCCA) and neuron-specific enolase (NSE) has been investigated in non-small-cell lung cancer (NSCLC) patients. However, few studies have directly focused on the association between these markers and epidermal growth factor receptor (EGFR) mutation status or mutation subtypes. Patients and methods We retrospectively analyzed 1016 patients with stage I-IIIA NSCLC who underwent complete resection between 2008 and 2012. Correlations between serum tumor marker levels and EGFR mutations and survival parameters were analyzed and prognostic factors were identified. Results Cyfra21-1 levels (P = 0.032 for disease-free survival [DFS]; P CEA levels (P CEA (P = 0.005) and clinical stage were predictive factors of DFS, while elevated CEA (P = 0.005) and Cyfra21-1 (P = 0.027) were independent prognostic factors. Conclusion Cyfra21-1 and CEA exhibit different predictive and prognostic values between EGFR-mutated and wild-type adenocarcinomas, as well as between EGFR mutation subtypes. The prognostic impact of preoperative serum tumor markers should be evaluated together with EGFR mutation status. PMID:27072585

Statistical guidance for experimental design and data analysis of mutation detection in rare monogenic mendelian diseases by exome sequencing.

Directory of Open Access Journals (Sweden)

Degui Zhi

Full Text Available Recently, whole-genome sequencing, especially exome sequencing, has successfully led to the identification of causal mutations for rare monogenic Mendelian diseases. However, it is unclear whether this approach can be generalized and effectively applied to other Mendelian diseases with high locus heterogeneity. Moreover, the current exome sequencing approach has limitations such as false positive and false negative rates of mutation detection due to sequencing errors and other artifacts, but the impact of these limitations on experimental design has not been systematically analyzed. To address these questions, we present a statistical modeling framework to calculate the power, the probability of identifying truly disease-causing genes, under various inheritance models and experimental conditions, providing guidance for both proper experimental design and data analysis. Based on our model, we found that the exome sequencing approach is well-powered for mutation detection in recessive, but not dominant, Mendelian diseases with high locus heterogeneity. A disease gene responsible for as low as 5% of the disease population can be readily identified by sequencing just 200 unrelated patients. Based on these results, for identifying rare Mendelian disease genes, we propose that a viable approach is to combine, sequence, and analyze patients with the same disease together, leveraging the statistical framework presented in this work.

Generation of induced pluripotent stem cells (iPSCs from a Bernard–Soulier syndrome patient carrying a W71R mutation in the GPIX gene

Directory of Open Access Journals (Sweden)

Lourdes Lopez-Onieva

2016-05-01

Full Text Available We generated an induced pluripotent stem cell (iPSC line from a Bernard–Soulier Syndrome (BSS patient carrying the mutation p.Trp71Arg in the GPIX locus (BSS1-PBMC-iPS4F4. Peripheral blood mononuclear cells (PBMCs were reprogrammed using heat sensitive non-integrative Sendai viruses containing the reprogramming factors Oct3/4, SOX2, KLF4 and c-MYC. Successful silencing of the exogenous reprogramming factors was checked by RT-PCR. Characterization of BSS1-PBMC-iPS4F4 included mutation analysis of GPIX locus, Short Tandem Repeats (STR profiling, alkaline phosphatase enzymatic activity, analysis of conventional pluripotency-associated factors at mRNA and protein level and in vivo differentiation studies. BSS1-PBMC-iPS4F4 will provide a powerful tool to study BSS.

Integrative proteomics, genomics, and translational immunology approaches reveal mutated forms of Proteolipid Protein 1 (PLP1) and mutant-specific immune response in multiple sclerosis.

Science.gov (United States)

Qendro, Veneta; Bugos, Grace A; Lundgren, Debbie H; Glynn, John; Han, May H; Han, David K

2017-03-01

In order to gain mechanistic insights into multiple sclerosis (MS) pathogenesis, we utilized a multi-dimensional approach to test the hypothesis that mutations in myelin proteins lead to immune activation and central nervous system autoimmunity in MS. Mass spectrometry-based proteomic analysis of human MS brain lesions revealed seven unique mutations of PLP1; a key myelin protein that is known to be destroyed in MS. Surprisingly, in-depth genomic analysis of two MS patients at the genomic DNA and mRNA confirmed mutated PLP1 in RNA, but not in the genomic DNA. Quantification of wild type and mutant PLP RNA levels by qPCR further validated the presence of mutant PLP RNA in the MS patients. To seek evidence linking mutations in abundant myelin proteins and immune-mediated destruction of myelin, specific immune response against mutant PLP1 in MS patients was examined. Thus, we have designed paired, wild type and mutant peptide microarrays, and examined antibody response to multiple mutated PLP1 in sera from MS patients. Consistent with the idea of different patients exhibiting unique mutation profiles, we found that 13 out of 20 MS patients showed antibody responses against specific but not against all the mutant-PLP1 peptides. Interestingly, we found mutant PLP-directed antibody response against specific mutant peptides in the sera of pre-MS controls. The results from integrative proteomic, genomic, and immune analyses reveal a possible mechanism of mutation-driven pathogenesis in human MS. The study also highlights the need for integrative genomic and proteomic analyses for uncovering pathogenic mechanisms of human diseases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A novel mutation of PAX3 in a Chinese family with Waardenburg syndrome.

Science.gov (United States)

Qin, Wei; Shu, Anli; Qian, Xueqing; Gao, Jianjun; Xing, Qinghe; Zhang, Juan; Zheng, Yonglan; Li, Xingwang; Li, Sheng; Feng, Guoyin; He, Lin

2006-08-28

The molecular characterization of 34 members of a Chinese family, with 22 members in four generations, affected with Waardenburg syndrome (WS1). A detailed family history and clinical data were collected. A genome-wide scan by two-point linkage analysis using more than 400 microsatellite markers in combination with haplotype analysis was performed. Mutation screening was carried out in the candidate gene by sequencing of amplified products. A maximum two-point lod score of 6.53 at theta = 0.00 was obtained with marker D2S2248. Haplotype analysis placed the WS1 locus to a 45.74 cM region between D2S117 and D2S206, in close proximity to the PAX3 gene on chromosome 2q35. Mutation screening in PAX3 identified a 701T > C mutation which converted a highly conserved Leu to Pro. This nucleotide alteration was neither seen in unaffected members of the family nor found in 50 unrelated control subjects. The present study identified a novel 701T > C mutation in PAX3. The mutation observed in this family highlights the phenotypic heterogeneity of the disorder.

Meiotic drive influences the outcome of sexually antagonistic selection at a linked locus.

Science.gov (United States)

Patten, M M

2014-11-01

Most meiotic drivers, such as the t-haplotype in Mus and the segregation distorter (SD) in Drosophila, act in a sex-specific manner, gaining a transmission advantage through one sex although suffering only the fitness costs associated with the driver in the other. Their inheritance is thus more likely through one of the two sexes, a property they share with sexually antagonistic alleles. Previous theory has shown that pairs of linked loci segregating for sexually antagonistic alleles are more likely to remain polymorphic and that linkage disequilibrium accrues between them. I probe this similarity between drive and sexual antagonism and examine the evolution of chromosomes experiencing these selection pressures simultaneously. Reminiscent of previous theory, I find that: the opportunity for polymorphism increases for a sexually antagonistic locus that is physically linked to a driving locus; the opportunity for polymorphism at a driving locus also increases when linked to a sexually antagonistic locus; and stable linkage disequilibrium accompanies any polymorphic equilibrium. Additionally, I find that drive at a linked locus favours the fixation of sexually antagonistic alleles that benefit the sex in which drive occurs. Further, I show that under certain conditions reduced recombination between these two loci is selectively favoured. These theoretical results provide clear, testable predictions about the nature of sexually antagonistic variation on driving chromosomes and have implications for the evolution of genomic architecture. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Tumor-specific mutations in low-frequency genes affect their functional properties

NARCIS (Netherlands)

L. Erdem-Eraslan (Lale); D. Heijsman (Daphne); M. De Wit (Maurice); A.E. Kremer (Andreas); A. Sacchetti (Andrea); P.J. van der Spek (Peter); P.A.E. Sillevis Smitt (Peter); P.J. French (Pim)

2015-01-01

textabstractCausal genetic changes in oligodendrogliomas (OD) with 1p/19q co-deletion include mutations in IDH1, IDH2, CIC, FUBP1, TERT promoter and NOTCH1. However, it is generally assumed that more somatic mutations are required for tumorigenesis. This study aimed to establish whether genes

Spectrum of mutations in CRM-positive and CRM-reduced hemophilia A

Energy Technology Data Exchange (ETDEWEB)

McGinniss, M.J.; Kazazian, H.H. Jr.; Bi, L.; Antonarakis, S.E. (John Hopkins Univ., Baltimore, MD (United States)); Hoyer, L.W. (American Red Cross Blood Services, Rockville, MD (United States)); Inaba, H. (Tokyo Medical College (Japan))

1993-02-01

Hemophilia A is due to the functional deficiency of factor VIII (FVIII, gene locus F8C). Although half the patients have no detectable FVIII protein in their plasma, the more rare patients ([approximately]5%) have normal levels of a dysfunctional FVIII and are termed cross-reacting material (CRM)-positive. More commonly ([approximately]45%), patients have plasma FVIII protein reduced to an extent roughly comparable to the level of FVIII activity and are designated CRM-reduced. We used denaturing gradient gel electrophoresis to screen for mutations within the F8C gene of 11 patients (6CRM-positive, 5 CRM-reduced) and identified 9 different mutations in 9 patients after analyses of all 26 exons, the promoter region, and the polyadenylation site. Six mutations have not been described previously. Five weree missense (Ser289Leu, Ser558Phe, Val634Ala, Val634Met, Asn1441Lys), and the sixth was a 3-bp deletion ([Delta]Phe652). A review of the literature and the assay of FVIII antigen in 5 hemophilia A patients with previously identified missense mutations from this laboratory yielded a total of 20 other unique CRM-reduced and CRM-positive mutations. Almost all CRM-positive/reduced mutations (24/26) were missense, and many (12/26) occurred at CpG dinucleotides. We examined 19 missense mutation for evolutionary conservation using the portions of the porcine and murine F8C sequences that are known, and 18/19 amino acid residue altered by mutation in these patients wer conserved. Almost 50% of mutations (11/26) clustered in the A2 domain, suggesting that this region is critical for the function of FVIII. The results indicate a nonrandom distribution of mutations and suggest that mutations in a limited number of FVIII regions may cause CRM-positive and CRM-reduced heomphilia A. 48 refs., 1 fig., 1 tab.

Mutation-Specific Mechanisms of Hyperactivation of Noonan Syndrome SOS Molecules Detected with Single-molecule Imaging in Living Cells.

Science.gov (United States)

Nakamura, Yuki; Umeki, Nobuhisa; Abe, Mitsuhiro; Sako, Yasushi

2017-10-26

Noonan syndrome (NS) is a congenital hereditary disorder associated with developmental and cardiac defects. Some patients with NS carry mutations in SOS, a guanine nucleotide exchange factor (GEF) for the small GTPase RAS. NS mutations have been identified not only in the GEF domain, but also in various domains of SOS, suggesting that multiple mechanisms disrupt SOS function. In this study, we examined three NS mutations in different domains of SOS to clarify the abnormality in its translocation to the plasma membrane, where SOS activates RAS. The association and dissociation kinetics between SOS tagged with a fluorescent protein and the living cell surface were observed in single molecules. All three mutants showed increased affinity for the plasma membrane, inducing excessive RAS signalling. However, the mechanisms by which their affinity was increased were specific to each mutant. Conformational disorder in the resting state, increased probability of a conformational change on the plasma membrane, and an increased association rate constant with the membrane receptor are the suggested mechanisms. These different properties cause the specific phenotypes of the mutants, which should be rescuable with different therapeutic strategies. Therefore, single-molecule kinetic analyses of living cells are useful for the pathological analysis of genetic diseases.

Distributions of Mutational Effects and the Estimation of Directional Selection in Divergent Lineages of Arabidopsis thaliana.

Science.gov (United States)

Park, Briton; Rutter, Matthew T; Fenster, Charles B; Symonds, V Vaughan; Ungerer, Mark C; Townsend, Jeffrey P

2017-08-01

Mutations are crucial to evolution, providing the ultimate source of variation on which natural selection acts. Due to their key role, the distribution of mutational effects on quantitative traits is a key component to any inference regarding historical selection on phenotypic traits. In this paper, we expand on a previously developed test for selection that could be conducted assuming a Gaussian mutation effect distribution by developing approaches to also incorporate any of a family of heavy-tailed Laplace distributions of mutational effects. We apply the test to detect directional natural selection on five traits along the divergence of Columbia and Landsberg lineages of Arabidopsis thaliana , constituting the first test for natural selection in any organism using quantitative trait locus and mutation accumulation data to quantify the intensity of directional selection on a phenotypic trait. We demonstrate that the results of the test for selection can depend on the mutation effect distribution specified. Using the distributions exhibiting the best fit to mutation accumulation data, we infer that natural directional selection caused divergence in the rosette diameter and trichome density traits of the Columbia and Landsberg lineages. Copyright © 2017 by the Genetics Society of America.

Mitochondrial mutations in subjects with psychiatric disorders.

Directory of Open Access Journals (Sweden)

Adolfo Sequeira

Full Text Available A considerable body of evidence supports the role of mitochondrial dysfunction in psychiatric disorders and mitochondrial DNA (mtDNA mutations are known to alter brain energy metabolism, neurotransmission, and cause neurodegenerative disorders. Genetic studies focusing on common nuclear genome variants associated with these disorders have produced genome wide significant results but those studies have not directly studied mtDNA variants. The purpose of this study is to investigate, using next generation sequencing, the involvement of mtDNA variation in bipolar disorder, schizophrenia, major depressive disorder, and methamphetamine use. MtDNA extracted from multiple brain regions and blood were sequenced (121 mtDNA samples with an average of 8,800x coverage and compared to an electronic database containing 26,850 mtDNA genomes. We confirmed novel and rare variants, and confirmed next generation sequencing error hotspots by traditional sequencing and genotyping methods. We observed a significant increase of non-synonymous mutations found in individuals with schizophrenia. Novel and rare non-synonymous mutations were found in psychiatric cases in mtDNA genes: ND6, ATP6, CYTB, and ND2. We also observed mtDNA heteroplasmy in brain at a locus previously associated with schizophrenia (T16519C. Large differences in heteroplasmy levels across brain regions within subjects suggest that somatic mutations accumulate differentially in brain regions. Finally, multiplasmy, a heteroplasmic measure of repeat length, was observed in brain from selective cases at a higher frequency than controls. These results offer support for increased rates of mtDNA substitutions in schizophrenia shown in our prior results. The variable levels of heteroplasmic/multiplasmic somatic mutations that occur in brain may be indicators of genetic instability in mtDNA.

Locus-specific ribosomal RNA gene silencing in nucleolar dominance.

Directory of Open Access Journals (Sweden)

Michelle S Lewis

2007-08-01

Full Text Available The silencing of one parental set of rRNA genes in a genetic hybrid is an epigenetic phenomenon known as nucleolar dominance. We showed previously that silencing is restricted to the nucleolus organizer regions (NORs, the loci where rRNA genes are tandemly arrayed, and does not spread to or from neighboring protein-coding genes. One hypothesis is that nucleolar dominance is the net result of hundreds of silencing events acting one rRNA gene at a time. A prediction of this hypothesis is that rRNA gene silencing should occur independent of chromosomal location. An alternative hypothesis is that the regulatory unit in nucleolar dominance is the NOR, rather than each individual rRNA gene, in which case NOR localization may be essential for rRNA gene silencing. To test these alternative hypotheses, we examined the fates of rRNA transgenes integrated at ectopic locations. The transgenes were accurately transcribed in all independent transgenic Arabidopsis thaliana lines tested, indicating that NOR localization is not required for rRNA gene expression. Upon crossing the transgenic A. thaliana lines as ovule parents with A. lyrata to form F1 hybrids, a new system for the study of nucleolar dominance, the endogenous rRNA genes located within the A. thaliana NORs are silenced. However, rRNA transgenes escaped silencing in multiple independent hybrids. Collectively, our data suggest that rRNA gene activation can occur in a gene-autonomous fashion, independent of chromosomal location, whereas rRNA gene silencing in nucleolar dominance is locus-dependent.

Diphtheria toxin resistance in human lymphocytes and lymphoblasts in the in vivo somatic cell mutation test

International Nuclear Information System (INIS)

Tomkins, D.J.; Wei, L.; Laurie, K.E.

1985-01-01

It has been shown that circulating peripheral blood lymphocytes can be used for the enumeration of 6-thioguanine-resistant cells that presumably arise by mutation in vivo. This somatic cell mutation test has been studied in lymphocytes from human populations exposed to known mutagens and/or carcinogens. The sensitivity of the test could be further enhanced by including other gene markers, since there is evidence for locus-specific differences in response to mutagens. Resistance to diphtheria toxin (Dip/sup r/) seemed like a potential marker to incorporate into the test because the mutation acts codominantly, can readily be selected in human diploid fibroblasts and Chinese hamster cells with no evidence for cell density or cross-feeding effects, and can be assayed for in nondividing cells by measuring protein synthesis inhibition. Blood samples were collected from seven individuals, and fresh, cryopreserved, or Epstein-Barr virus (EBV)-transformed lymphocytes were tested for continued DNA synthesis ( 3 H-thymidine, autoradiography) or protein synthesis ( 35 S-methionine, scintillation counting). Both fresh and cryopreserved lymphocytes, stimulated to divide with phytohemagglutinin (PHA), continued to synthesize DNA in the presence of high doses of diphtheria toxin (DT). Similarly, both dividing (PHA-stimulated) and nondividing fresh lymphocytes carried on significant levels of protein synthesis even 68 hr after exposure to 100 flocculating units (LF)/ml DT. The results suggest that human T and B lymphocytes may not be as sensitive to DT protein synthesis inhibition as human fibroblast and Chinese hamster cells. For this reason, Dip/sup r/ may not be a suitable marker for the somatic cell mutation test

Novel mutations of MYO7A and USH1G in Israeli Arab families with Usher syndrome type 1.

Science.gov (United States)

Rizel, Leah; Safieh, Christine; Shalev, Stavit A; Mezer, Eedy; Jabaly-Habib, Haneen; Ben-Neriah, Ziva; Chervinsky, Elena; Briscoe, Daniel; Ben-Yosef, Tamar

2011-01-01

This study investigated the genetic basis for Usher syndrome type 1 (USH1) in four consanguineous Israeli Arab families. Haplotype analysis for all known USH1 loci was performed in each family. In families for which haplotype analysis was inconclusive, we performed genome-wide homozygosity mapping using a single nucleotide polymorphism (SNP) array. For mutation analysis, specific primers were used to PCR amplify the coding exons of the MYO7A, USH1C, and USH1G genes including intron-exon boundaries. Mutation screening was performed with direct sequencing. A combination of haplotype analysis and genome-wide homozygosity mapping indicated linkage to the USH1B locus in two families, USH1C in one family and USH1G in another family. Sequence analysis of the relevant genes (MYO7A, USH1C, and USH1G) led to the identification of pathogenic mutations in all families. Two of the identified mutations are novel (c.1135-1147dup in MYO7A and c.206-207insC in USH1G). USH1 is a genetically heterogenous condition. Of the five USH1 genes identified to date, USH1C and USH1G are the rarest contributors to USH1 etiology worldwide. It is therefore interesting that two of the four Israeli Arab families reported here have mutations in these two genes. This finding further demonstrates the unique genetic structure of the Israeli population in general, and the Israeli Arab population in particular, which due to high rates of consanguinity segregates many rare autosomal recessive genetic conditions.

Comparing health locus of control in patients with Spasmodic Dysphonia, Functional Dysphonia and Nonlaryngeal Dystonia.

Science.gov (United States)

Haselden, Karen; Powell, Theresa; Drinnan, Mike; Carding, Paul

2009-11-01

Locus of Control (LoC) refers to an individuals' perception of whether they are in control of life events. Health Locus of Control refers to whether someone feels they have influence over their health. Health Locus of Control has not been studied in any depth in voice-disordered patients. The objective of this study was to examine Health Locus of Control in three patient groups: (1) Spasmodic Dysphonia, (2) Functional Dysphonia and (3) a nondysphonic group with Nonlaryngeal Dystonia. LoC was measured and compared in a total of 57 patients using the Multidimensional Health Locus of Control Scales (diagnostic specific) Form C. Internal, Chance, and Powerful others LoC were measured and comparisons were made using one-way analysis of variance. Contrary to expectations Internal LoC was found to be significantly higher in the Functional Dysphonia group when compared to the other two groups. There was no significant difference between the groups in Chance or Powerful others LoC. The two organic groups, Spasmodic Dysphonia and Nonlaryngeal Dystonia, were more alike in Internal Health Locus of Control than the Functional Dysphonia group. The diagnostic nature of the groups was reflected in their LoC scores rather than their voice loss. These results contribute to the debate about the etiology of Spasmodic Dysphonia and will be of interest to those involved in the psychology of voice and those managing voice-disordered patients.

Haemophilia B caused by mutation of a potential thrombin cleavage site in factor IX

Energy Technology Data Exchange (ETDEWEB)

Winship, P.R. (Univ. of Oxford (England))

1990-03-11

Haemophilia B is a blood coagulation disorder caused by mutations in the factor IX gene giving functionally defective or reduced levels of factor IX protein circulating in the plasma. The mutation in the Caucasian patient under investigation, Haemophilia B Oxford h5 (Oxh5), was characterized at the DNA level by constructing a genomic library using leucocyte-derived DNA from the patient. Overlapping recombinant clones spanning the entire factor IX locus were isolated which then allowed the generation of a series of sub-clones across all eight exons (a-h) plus the 5{prime} and 3{prime} flanking sequences known to be important in regulation of the gene and polyadenylation of the mRNA species.

Fine-Scale Mapping at 9p22.2 Identifies Candidate Causal Variants That Modify Ovarian Cancer Risk in BRCA1 and BRCA2 Mutation Carriers.

Directory of Open Access Journals (Sweden)

Elena Vigorito

Full Text Available Population-based genome wide association studies have identified a locus at 9p22.2 associated with ovarian cancer risk, which also modifies ovarian cancer risk in BRCA1 and BRCA2 mutation carriers. We conducted fine-scale mapping at 9p22.2 to identify potential causal variants in BRCA1 and BRCA2 mutation carriers. Genotype data were available for 15,252 (2,462 ovarian cancer cases BRCA1 and 8,211 (631 ovarian cancer cases BRCA2 mutation carriers. Following genotype imputation, ovarian cancer associations were assessed for 4,873 and 5,020 SNPs in BRCA1 and BRCA 2 mutation carriers respectively, within a retrospective cohort analytical framework. In BRCA1 mutation carriers one set of eight correlated candidate causal variants for ovarian cancer risk modification was identified (top SNP rs10124837, HR: 0.73, 95%CI: 0.68 to 0.79, p-value 2× 10-16. These variants were located up to 20 kb upstream of BNC2. In BRCA2 mutation carriers one region, up to 45 kb upstream of BNC2, and containing 100 correlated SNPs was identified as candidate causal (top SNP rs62543585, HR: 0.69, 95%CI: 0.59 to 0.80, p-value 1.0 × 10-6. The candidate causal in BRCA1 mutation carriers did not include the strongest associated variant at this locus in the general population. In sum, we identified a set of candidate causal variants in a region that encompasses the BNC2 transcription start site. The ovarian cancer association at 9p22.2 may be mediated by different variants in BRCA1 mutation carriers and in the general population. Thus, potentially different mechanisms may underlie ovarian cancer risk for mutation carriers and the general population.

A novel gene for Usher syndrome type 2: mutations in the long isoform of whirlin are associated with retinitis pigmentosa and sensorineural hearing loss.

Science.gov (United States)

Ebermann, Inga; Scholl, Hendrik P N; Charbel Issa, Peter; Becirovic, Elvir; Lamprecht, Jürgen; Jurklies, Bernhard; Millán, José M; Aller, Elena; Mitter, Diana; Bolz, Hanno

2007-04-01

Usher syndrome is an autosomal recessive condition characterized by sensorineural hearing loss, variable vestibular dysfunction, and visual impairment due to retinitis pigmentosa (RP). The seven proteins that have been identified for Usher syndrome type 1 (USH1) and type 2 (USH2) may interact in a large protein complex. In order to identify novel USH genes, we followed a candidate strategy, assuming that mutations in proteins interacting with this "USH network" may cause Usher syndrome as well. The DFNB31 gene encodes whirlin, a PDZ scaffold protein with expression in both hair cell stereocilia and retinal photoreceptor cells. Whirlin represents an excellent candidate for USH2 because it binds to Usherin (USH2A) and VLGR1b (USH2C). Genotyping of microsatellite markers specific for the DFNB31 gene locus on chromosome 9q32 was performed in a German USH2 family that had been excluded for all known USH loci. Patients showed common haplotypes. Sequence analysis of DFNB31 revealed compound heterozygosity for a nonsense mutation, p.Q103X, in exon 1, and a mutation in the splice donor site of exon 2, c.837+1G>A. DFNB31 mutations appear to be a rare cause of Usher syndrome, since no mutations were identified in an additional 96 USH2 patients. While mutations in the C-terminal half of whirlin have previously been reported in non-syndromic deafness (DFNB31), both alterations identified in our USH2 family affect the long protein isoform. We propose that mutations causing Usher syndrome are probably restricted to exons 1-6 that are specific for the long isoform and probably crucial for retinal function. We describe a novel genetic subtype for Usher syndrome, which we named USH2D and which is caused by mutations in whirlin. Moreover, this is the first case of USH2 that is allelic to non-syndromic deafness.

Functional Analysis of the Coronary Heart Disease Risk Locus on Chromosome 21q22

Directory of Open Access Journals (Sweden)

Katherine E. Beaney

2017-01-01

Full Text Available Background. The coronary heart disease (CHD risk locus on 21q22 (lead SNP rs9982601 lies within a “gene desert.” The aim of this study was to assess if this locus is associated with CHD risk factors and to identify the functional variant(s and gene(s involved. Methods. A phenome scan was performed with UCLEB Consortium data. Allele-specific protein binding was studied using electrophoretic mobility shift assays. Dual-reporter luciferase assays were used to assess the impact of genetic variation on expression. Expression quantitative trait analysis was performed with Advanced Study of Aortic Pathology (ASAP and Genotype-Tissue Expression (GTEx consortium data. Results. A suggestive association between QT interval and the locus was observed (rs9982601  p=0.04. One variant at the locus, rs28451064, showed allele-specific protein binding and its minor allele showed 12% higher luciferase expression (p = 4.82 × 10−3 compared to the common allele. The minor allele of rs9982601 was associated with higher expression of the closest upstream genes (SLC5A3 1.30-fold increase p = 3.98 × 10−5; MRPS6 1.15-fold increase p = 9.60 × 10−4 in aortic intima media in ASAP. Both rs9982601 and rs28451064 showed a suggestive association with MRPS6 expression in relevant tissues in the GTEx data. Conclusions. A candidate functional variant, rs28451064, was identified. Future work should focus on identifying the pathway(s involved.

[Cochlear implantation in a child with congenital sensorineural deafness due to 35 DELG mutation in GJB2 (connexin 26) gene].

Science.gov (United States)

Teriutin, F M; Barashkov, N A; Dzhemileva, L U; Posukh, O L; Fedotova, E E; Gurinova, E E; Fedorova, S A; Tavartkiladze, G A; Khusnutdinova, E K

2009-01-01

This paper reports the first case of cochlear implantation performed in this country in a child with congenital non-syndromic sensorineural loss of hearing having hereditary etiology and attributable to autosomal-recessive 35 delG mutation in locus DFNB1 (13q.11-q12) of GJB2 (connexin 26) gene.

An in vivo cis-regulatory screen at the type 2 diabetes associated TCF7L2 locus identifies multiple tissue-specific enhancers.

Directory of Open Access Journals (Sweden)

Daniel Savic

Full Text Available Genome-wide association studies (GWAS have repeatedly shown an association between non-coding variants in the TCF7L2 locus and risk for type 2 diabetes (T2D, implicating a role for cis-regulatory variation within this locus in disease etiology. Supporting this hypothesis, we previously localized complex regulatory activity to the TCF7L2 T2D-associated interval using an in vivo bacterial artificial chromosome (BAC enhancer-trapping reporter strategy. To follow-up on this broad initial survey of the TCF7L2 regulatory landscape, we performed a fine-mapping enhancer scan using in vivo mouse transgenic reporter assays. We functionally interrogated approximately 50% of the sequences within the T2D-associated interval, utilizing sequence conservation within this 92-kb interval to determine the regulatory potential of all evolutionary conserved sequences that exhibited conservation to the non-eutherian mammal opossum. Included in this study was a detailed functional interrogation of sequences spanning both protective and risk alleles of single nucleotide polymorphism (SNP rs7903146, which has exhibited allele-specific enhancer function in pancreatic beta cells. Using these assays, we identified nine segments regulating various aspects of the TCF7L2 expression profile and that constitute nearly 70% of the sequences tested. These results highlight the regulatory complexity of this interval and support the notion that a TCF7L2 cis-regulatory disruption leads to T2D predisposition.

Evaluation and re-evaluation of genetic radiation hazards in man

International Nuclear Information System (INIS)

Schalet, A.P.; Sankaranarayanan, K.

1976-01-01

A detailed presentation is made of the experimental data from the various systems used by Abrahamson to conclude that the per locus per rad (low LET) radiation-induced forward mutation rates in organisms whose DNA content varies by a factor of about 1000, is proportional to genome size. Additional information pertinent in this context is also reviewed. It is emphasized that the mutation rates cited by Abrahamson, although considered as pertaining to mutations at specific loci, actually derive from a broad variety of genetic end-points. It is argued that an initial (if not sufficient) condition for sound interspecific mutation rate comparisons, covering a wide range of organisms and detecting systems of various sensitivities, requires a reasonably consistent biological definition of a specific locus mutation, namely, a transmissible intralocus change. Granting the differences between systems in their resolving power to detect intergenic change, the data cited in this paper do not support the existence of a simple proportionality between radiation-induced intralocus mutation rate and genome size for the different species reviewed here

HS5 of the human β-globin Locus Control Region: a developmental stage-specific border in erythroid cells.

NARCIS (Netherlands)

A. Wai (Albert); N. Gillemans (Nynke); S. Raguz-Bolognesi (Selina); S. Pruzina (Sara); G. Zafarana (Gaetano); D.N. Meijer (Dies); F.G. Grosveld (Frank); J.N.J. Philipsen (Sjaak)

2003-01-01

textabstractElements with insulator/border activity have been characterized most extensively in Drosophila melanogaster. In vertebrates, the first example of such an element was provided by a hypersensitive site of the chicken beta-globin locus, cHS4. It has been proposed that the homologous site in

Methylation and Transcripts Expression at the Imprinted GNAS Locus in Human Embryonic and Induced Pluripotent Stem Cells and Their Derivatives

Directory of Open Access Journals (Sweden)

Virginie Grybek

2014-09-01

Full Text Available Data from the literature indicate that genomic imprint marks are disturbed in human pluripotent stem cells (PSCs. GNAS is an imprinted locus that produces one biallelic (Gsα and four monoallelic (NESP55, GNAS-AS1, XLsα, and A/B transcripts due to differential methylation of their promoters (DMR. To document imprinting at the GNAS locus in PSCs, we studied GNAS locus DMR methylation and transcript (NESP55, XLsα, and A/B expression in human embryonic stem cells (hESCs and human induced pluripotent stem cells (hiPSCs derived from two human fibroblasts and their progenies. Results showed that (1 methylation at the GNAS locus DMRs is DMR and cell line specific, (2 changes in allelic transcript expression can be independent of a change in allele-specific DNA methylation, and (3 interestingly, methylation at A/B DMR is correlated with A/B transcript expression. These results indicate that these models are valuable to study the mechanisms controlling GNAS methylation, factors involved in transcript expression, and possibly mechanisms involved in the pathophysiology of pseudohypoparathyroidism type 1B.

aprABC: A Mycobacterium tuberculosis complex-specific locus that modulates pH-driven adaptation to the macrophage phagosome

Science.gov (United States)

Abramovitch, Robert B.; Rohde, Kyle H.; Hsu, Fong-Fu; Russell, David G.

2011-01-01

Summary Following phagocytosis by macrophages, Mycobacterium tuberculosis (Mtb) senses the intracellular environment and remodels its gene expression for growth in the phagosome. We have identified an Acid and Phagosome Regulated (aprABC) locus that is unique to the Mtb complex and whose gene expression is induced during growth in acidic environments in vitro and in macrophages. Using the aprA promoter, we generated a strain that exhibits high levels of inducible fluorescence in response to growth in acidic medium in vitro and in macrophages. aprABC expression is dependent on the two-component regulator phoPR, linking phoPR signaling to pH sensing. Deletion of the aprABC locus causes defects in gene expression that impact aggregation, intracellular growth, and the relative levels of storage and cell wall lipids. We propose a model where phoPR senses the acidic pH of the phagosome and induces aprABC expression to fine-tune processes unique for intracellular adaptation of Mtb complex bacteria. PMID:21401735

An erythrocyte-specific DNA-binding factor recognizes a regulatory sequence common to all chicken globin genes

International Nuclear Information System (INIS)

Evans, T.; Reitman, M.; Felsenfeld, G.

1988-01-01

The authors have identified a protein present only in erythroid cells that binds to two adjacent sites within an enhancer region of the chicken β-globin locus. Mutation of the sites, so that binding by the factor can no longer be detected in vitro, leads to a loss of enhancing ability, assayed by transient expression in primary erythrocytes. Binding sites for the erythroid-specific factor (Eryf1) are found within regulatory regions for all chicken globin genes. A strong Eryf1 binding site is also present within the enhancer of at least one human globin gene, and proteins from human erythroid cells (but not HeLa cells) bind to both the chicken and the human sites

Mutational analysis of Peroxiredoxin IV: exclusion of a positional candidate for multinodular goitre

Directory of Open Access Journals (Sweden)

Bonifazi Emanuela

2002-07-01

Full Text Available Abstract Background Multinodular goitre (MNG is a common disorder characterised by an enlargement of the thyroid, occurring as a compensatory response to hormonogenesis impairment. The incidence of MNG is dependent on sex (female:male ratio 5:1 and several reports have documented a genetic basis for the disease. Last year we mapped a MNG locus to chromosome Xp22 in a region containing the peroxiredoxin IV (Prx-IV gene. Since Prx-IV is involved in the removal of H2O2 in thyroid cells, we hypothesize that mutations in Prx-IV gene are involved in pathogenesis of MNG. Methods Four individuals (2 affected, 2 unrelated unaffected were sequenced using automated methods. All individuals were originated from the original three-generation Italian family described in previous studies. A Southern blot analysis using a Prx-IV full-length cDNA as a probe was performed in order to exclude genomic rearrangements and/or intronic mutations. In addition a RT-PCR of PRX-IV was performed in order to investigate expression alterations. Results No causative mutations were found. Two adjacent nucleotide substitutions were detected within introns 1 and 4. These changes were also detected in unaffected individuals, suggesting that they were innocuous polymorphisms. No gross genomic rearrangements and/or restriction fragment alterations were observed on Southern analysis. Finally, using RT-PCR from tissue-specific RNA, no differences of PRX-IV expression-levels were detected between affected and unaffected samples. Conclusions Based on sequence and genomic analysis, Prx-IV is very unlikely to be the MNG2 gene.

Genetic heterogeneity in familial exudative vitreoretinopathy; exclusion of the EVR1 locus on chromosome 11q in a large autosomal dominant pedigree

OpenAIRE

Bamashmus, M; Downey, L; Inglehearn, C; Gupta, S; Mansfield, D

2000-01-01

BACKGROUND/AIMS—Familial exudative vitreoretinopathy (FEVR) is associated with mutations in the Norrie disease gene in X linked pedigrees and with linkage to the EVR1 locus at 11q13 in autosomal dominant cases. A large autosomal dominant FEVR family was studied, both clinically and by linkage analysis, to determine whether it differed from the known forms of FEVR.
METHODS—Affected members and obligate gene carriers from this family were examined by slit lamp biomicroscopy, indirect ophthalmos...

Somatic mutation analysis of MYH11 in breast and prostate cancer

International Nuclear Information System (INIS)

Alhopuro, Pia; Karhu, Auli; Winqvist, Robert; Waltering, Kati; Visakorpi, Tapio; Aaltonen, Lauri A

2008-01-01

MYH11 (also known as SMMHC) encodes the smooth-muscle myosin heavy chain, which has a key role in smooth muscle contraction. Inversion at the MYH11 locus is one of the most frequent chromosomal aberrations found in acute myeloid leukemia. We have previously shown that MYH11 mutations occur in human colorectal cancer, and may also be associated with Peutz-Jeghers syndrome. The mutations found in human intestinal neoplasia result in unregulated proteins with constitutive motor activity, similar to the mutant myh11 underlying the zebrafish meltdown phenotype characterized by disrupted intestinal architecture. Recently, MYH1 and MYH9 have been identified as candidate breast cancer genes in a systematic analysis of the breast cancer genome. The aim of this study was to investigate the role of somatic MYH11 mutations in two common tumor types; breast and prostate cancers. A total of 155 breast cancer and 71 prostate cancer samples were analyzed for those regions in MYH11 (altogether 8 exons out of 42 coding exons) that harboured mutations in colorectal cancer in our previous study. In breast cancer samples only germline alterations were observed. One prostate cancer sample harbored a frameshift mutation c.5798delC, which we have previously shown to result in a protein with unregulated motor activity. Little evidence for a role of somatic MYH11 mutations in the formation of breast or prostate cancers was obtained in this study

The Impact of Locus of Control on Language Achievement

Science.gov (United States)

Nodoushan, Mohammad Ali Salmani

2012-01-01

This study hypothesized that students' loci of control affected their language achievement. 198 (N = 198) EFL students took the Rotter's (1966) locus of control test and were classified as locus-internal (ni = 78), and locus-external (ne = 120). They then took their ordinary courses and at the end of the semester, they were given their exams.…

Impact of locus of control on health message effectiveness.

Science.gov (United States)

Kong, Ying; Shen, Fuyuan

2011-10-01

This article examined how individuals' locus of control might moderate the effect of health message frames. An experiment was conducted whereby participants read either individual- or social-responsibility message frames after their locus of control was primed. Results indicated that messages presented in individual-responsibility frames were more persuasive when people were primed with internal locus of control, whereas social-responsibility framed appeals were more persuasive when people were primed with external locus of control. These results were found for individuals in both high and low cognitive load conditions. Theoretical and practical implications of the findings are discussed.

Note on guilt appeals in advertising: covariate effects of self-esteem and locus of control.

Science.gov (United States)

Pinto, M B; Worobetz, N D

1992-02-01

A 1991 study by Pinto and Priest demonstrated the effectiveness of advertisements employing moderate levels of guilt in inducing guilt responses in subjects. Because individuals' responses to guilt are often influenced by their specific personality characteristics, researchers have pointed to the potential moderating effects of individual difference variables such as level of self-esteem and locus of control on individuals' susceptibility to guilt appeals. A study was conducted to evaluate the possibility that self-esteem and locus of control can act as covariates across three treatment levels of guilt advertising. From a sample of 57 working mothers, advertisements stimulating medium and high levels of guilt elicited significantly greater feelings of guilt in subjects than the control advertisement stimulating low guilt. However, the relationship between susceptibility to guilt appeals and self-esteem and locus of control was not observed to covary.

Male Hypogonadism and Germ Cell Loss Caused by a Mutation in Polo-Like Kinase 4

Science.gov (United States)

Harris, Rebecca M.; Weiss, Jeffrey

2011-01-01

The genetic etiologies of male infertility remain largely unknown. To identify genes potentially involved in spermatogenesis and male infertility, we performed genome-wide mutagenesis in mice with N-ethyl-N-nitrosourea and identified a line with dominant hypogonadism and patchy germ cell loss. Genomic mapping and DNA sequence analysis identified a novel heterozygous missense mutation in the kinase domain of Polo-like kinase 4 (Plk4), altering an isoleucine to asparagine at residue 242 (I242N). Genetic complementation studies using a gene trap line with disruption in the Plk4 locus confirmed that the putative Plk4 missense mutation was causative. Plk4 is known to be involved in centriole formation and cell cycle progression. However, a specific role in mammalian spermatogenesis has not been examined. PLK4 was highly expressed in the testes both pre- and postnatally. In the adult, PLK4 expression was first detected in stage VIII pachytene spermatocytes and was present through step 16 elongated spermatids. Because the homozygous Plk4I242N/I242N mutation was embryonic lethal, all analyses were performed using the heterozygous Plk4+/I242N mice. Testis size was reduced by 17%, and histology revealed discrete regions of germ cell loss, leaving only Sertoli cells in these defective tubules. Testis cord formation (embryonic day 13.5) was normal. Testis histology was also normal at postnatal day (P)1, but germ cell loss was detected at P10 and subsequent ages. We conclude that the I242N heterozygous mutation in PLK4 is causative for patchy germ cell loss beginning at P10, suggesting a role for PLK4 during the initiation of spermatogenesis. PMID:21791561

Sex-specific effects of naturally occurring variants in the dopamine receptor D2 locus on insulin secretion and Type 2 diabetes susceptibility

DEFF Research Database (Denmark)

Guigas, B; de Leeuw van Weenen, J E; van Leeuwen, N

2014-01-01

AIMS: Modulation of dopamine receptor D2 (DRD2) activity affects insulin secretion in both rodents and isolated pancreatic β-cells. We hypothesized that single nucleotide polymorphisms in the DRD2/ANKK1 locus may affect susceptibility to Type 2 diabetes in humans. METHODS: Four potentially....... In addition, 340 Dutch subjects underwent a 2-h hyperglycaemic clamp to investigate insulin secretion. Since sexual dimorphic associations related to DRD2 polymorphisms have been previously reported, we also performed a gender-stratified analysis. RESULTS: rs1800497 at the DRD2/ANKK1 locus was associated...

Analysis of mutations in the human HPRT gene induced by accelerated heavy-ion irradiation