Direct Sequencing (direct + sequencing)

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Distribution within Medical Sciences

Terms modified by Direct Sequencing

  • direct sequencing analysis
  • direct sequencing method

  • Selected Abstracts


    A novel mutation in the PSEN1 gene (L286P) associated with familial early-onset dementia of Alzheimer type and lobar haematomas

    EUROPEAN JOURNAL OF NEUROLOGY, Issue 12 2007
    R. Sánchez-Valle
    The aim of this study was to describe a novel mutation in exon 8 of the presenilin gene (L286P) associated with early-onset autosomal dominant Alzheimer's disease (AD) and lobar haematomas. The proband was a woman who developed cognitive decline with predominant memory loss at the age of 35 years. The patient died at the age of 54 years and the neuropathological examination confirmed the diagnosis of AD. Three of her four siblings, one parent and one sibling of her parent had suffered from cognitive decline at ages between 35 and 42 years. Three of them also presented lobar haematomas. The neuropathological examination, available in one of them, disclosed the presence of severe amyloid angiopathy as the cause of the haematoma. The study of PSEN1 gene with single strand conformation polymorphism technique failed to show abnormalities suggestive of mutations. Direct sequencing disclosed the presence of a missense mutation in codon 286 (L286P) in the proband and her already affected descendent, which was absent in the healthy sibling. L286P is a novel mutation in PSEN1 that causes familial early-onset AD and brain haematomas related to amyloid angiopathy. [source]


    Erratum: A novel splice site mutation (3157+1G>T) in the dystrophin gene causing total exon skipping and DMD phenotype ,,

    HUMAN MUTATION, Issue 6 2001
    M. Sironi
    Abstract Erratum: An error was printed in the original version of this article in the Comments section, paragraph 2, relating to the size of exon 22 and the RT-PCR product size described as resulting from the mutation 3157+1G>T. The paragraph should read: "We report a case of a 5 year old DMD patient with a novel splice site mutation affecting the GT dinucleotide splice donor of exon 22. The RT-PCR analysis with primer sets spanning dystrophin exons 17-25 amplified no normal size fragment (1251 bp), but a product shorter by 146 bp (the length of exon 22). Direct sequencing of the faster migrating fragment revealed total skipping of exon 22." [source]


    A study on sequence variations in pre-S/surface, X and enhancer II/core promoter/precore regions of occult hepatitis B virus in non-B, non-C hepatocellular carcinoma patients in Taiwan

    INTERNATIONAL JOURNAL OF CANCER, Issue 3 2009
    Chien-Hung Chen
    Abstract This study was to investigate the clinical significance and virologic factors of occult hepatitis B virus (HBV) infection in hepatocellular carcinoma (HCC) patients without hepatitis B surface antigen (HBsAg) or anti-hepatitis C virus (non-B, non-C) in Taiwan. Serum HBV DNA (occult HBV) was detected in 90 of 222 non-B, non-C HCC patients and 24 of 300 non-B, non-C controls without HCC. Of 90 occult HBV-infected HCC patients, the sequences of HBV pre-S/surface, X and enhancer II/core promoter/precore genes were analyzed from 40 patients. Direct sequencing of such genes was also performed in 24 non-B, non-C controls without HCC and 40 HBsAg-positive HCC controls. Compared with non-B, non-C controls without HCC, non-B, non-C subjects with HCC had significantly higher prevalence of occult HBV (p < 0.0001). Moreover, M1I and Q2K in pre-S2 gene and G1721A were more common in occult HBV-infected patients with HCC than in those without HCC. Compared with the HBsAg-positive HCC controls, occult HBV-infected HCC patients had higher frequencies of M1I and Q2K in pre-S2 gene, G185R and S210N in surface gene, A36T and A44L in X gene, and G1721A in enhancer II gene, and had lower rates of pre-S deletions and A1762T/G1764A, A1846T, G1896A and G1899A in core promoter/precore genes. Multivariate analysis showed Q2K in pre-S2 gene, G1721A and A1846T were independent factors for occult HBV-infected HCC. Our study suggested that the virological factors of HBV related to HCC were different between occult HBV-infected and HBsAg-positive patients. The G1721A, M1I and Q2K in pre-S2 gene may be useful viral markers for HCC in occult HBV carriers. © 2009 UICC [source]


    Expression of inhibitors of apoptosis family protein in 7,12-dimethylbenz[a]anthracene-induced hamster buccal-pouch squamous-cell carcinogenesis is associated with mutant p53 accumulation and epigenetic changes

    INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 5 2008
    Shui-Sang Hsue
    Summary Fifty outbred Syrian golden hamsters were equally divided into three experimental groups and two control groups. The pouches of the experimental groups were painted bilaterally with a 0.5% 7,12-dimethylbenz[a]anthracene (DMBA) solution thrice a week for 3, 7 and 14 weeks. One of the control groups was applied with mineral oil while another control group remained untreated throughout the experiment. Neither survivin nor cIAP2 could be detected in any of the control tissues, whereas survivin and cIAP2 were found to be significantly increased in 3-, 7- and 14-week DMBA-treated pouches compared with the control pouches. Expression of XIAP, cIAP1 and NAIP were noted for both the control and 3-, 7- and 14-week DMBA-treated pouches, but levels were found to be significantly elevated in the experimental groups compared with the control pouches. p53 was not detected in any control tissues, but was significantly increased in 3-, 7- and 14-week DMBA-treated pouches. Direct sequencing revealed a point mutation (C,G) of p53 for pouch tissues treated with DMBA for 3 and 7 weeks, and there was a wide variation in the p53 sequence of the 14-week DMBA-treated pouch tissues, as compared with the control tissues. The control tissues had a survivin - and cIAP2 -methylated allele, whereas the DMBA-treated tissues showed no evidence of survivin - and cIAP2 -methylation. Neither the control nor DMBA-treated pouches showed evidence of XIAP -, cIAP1 - or NAIP -methylation. Our results suggest that the expression of inhibitors of apoptosis family in DMBA-induced hamster buccal-pouch squamous-cell carcinogenesis may be modulated by both genetic (mutant p53) and epigenetic mechanisms. [source]


    Coexistence of two mitochondrial DNA haplotypes in Japanese populations of Hypera postica (Col., Curculionidae)

    JOURNAL OF APPLIED ENTOMOLOGY, Issue 4 2005
    R. Kuwata
    Abstract:, In Japan, the alfalfa weevil, Hypera postica, was first recorded in 1982 from Fukuoka and Okinawa Prefectures and has been spreading to many other prefectures. The weevil seriously infests the Chinese milk vetch, Astragalus sinicus, one of the most important honey resources for honeybees in Japan. Direct sequencing of partial mitochondrial DNA and PCR-RFLP data for alfalfa weevil individuals indicated the coexistence of two haplotypes at various localities in Japan. Molecular phylogenetic analysis for H. postica haplotypes and strains indicated that the two Japanese haplotypes had not derived from a single genetic origin. Based on the results, special comments are made on biological control measures using introduced parasitic waSPS. [source]


    Elevated genetic heterogeneity and Pleistocene climatic instability: inferences from nrDNA in New Zealand Coprosma (Rubiaceae)

    JOURNAL OF BIOGEOGRAPHY, Issue 7 2002
    Stephen R. Wichman
    Aim To examine patterns of hybridization and genotype mixing within the genus Coprosma J.R.Forst. & G.Forst. (Rubiaceae). Location New Zealand Methods Nucleotide sequence was determined for the internal transcribed spacer (ITS) and external transcribed spacer (ETS) regions of nuclear ribosomal DNA for fifty individuals from thirty-six taxa within the New Zealand component of the genus Coprosma. Results Mixed sequences were found to be widespread in Coprosma. Direct sequencing of ITS polymerase chain reaction (PCR) products from seven polyploid taxa showed evidence of sequence mixtures. Cloning and sequencing of individual PCR products from two polyploids confirmed the presence of multiple templates, one of which corresponded to that of a diploid. Intra-individual heterogeneity was also seen in a hybrid diploid taxon, with the mixed nucleotides corresponding to those of the parental lineages. Finally the ITS sequences of twenty-two diploid taxa showed that eleven contained intra-individual heterogeneity. Conclusions We conclude that the widespread occurrence of sequence mixtures in Coprosma results from of frequent hybridization. We also conclude that concerted evolution of the ITS and ETS regions is depressed. We propose that these characteristics evolved as a mechanism to maintain high levels of heterogeneity and suggest that this is adaptive for Coprosma in climatically unstable and physically complex New Zealand landscapes. These landscapes have been subjected to repeated oscillations between stadial and interstadial environments during the Pleistocene. [source]


    Novel point mutation in exon 12 of the glucose-6- Phosphate Dehydrogenase Gene: G6PD Flores

    JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2004
    Maria-Odete Rodrigues
    Abstract In Portugal there are a wide variety of G6PD deficiency associated mutations. In an individual from the island of Flores of the Azorean archipelago, we report a new mutation in the G6PD gene that gives rise to a "moderate rate of G6PD deficiency" (12.6% of the normal activity) according to WHO criteria. Direct sequencing revealed a C,A point mutation at position 1387 with the consequent substitution of an Argine by Serine. We designated this new mutation as G6PD FLORES. The mutation is associated with haplotype I ( , , + + , , ), using six intragenic RFLPs. This information may also be seen as contributing to the clarification of the genetic makeup of the Azorean population, founder mutations, and/or gene flow. J. Clin. Lab. Anal. 18:129,131, 2004. © 2004 Wiley-Liss, Inc. [source]


    Can the serological status of "anti-HBc alone" be considered a sentinel marker for detection of "occult" HBV infection?

    JOURNAL OF MEDICAL VIROLOGY, Issue 4 2008
    Francesco Vitale
    Abstract Some individuals have "occult" infection with hepatitis B virus (HBV), defined as presence of HBV genome in the serum or liver tissue without HBV surface antigen (HBsAg) in the serum. The aim of this study was to investigate whether serum antibodies against HBV core antigen in isolation ("anti-HBc alone") are a useful marker of "occult" HBV in patients with or without hepatitis C virus (HCV) infection. "Anti-HBc alone" was detected in the sera of 119/6,544 (1.8%) asymptomatic outpatients referred to the diagnostic laboratory for routine testing for viral hepatitis, 62/607 (10.2%) drug users, and 42/195 (21.5%) patients with hepatocellular carcinoma. Using three in-house nested-PCR amplification assays to detect HBV preS-S (S), precore-core (C), and Pol viral regions, respectively, "occult" HBV sequences were found in 9 of the 223 sera (4.0%) with "anti-HBc alone." The highest prevalence of "occult" HBV sequences (5.9%) was detected in "anti-HBV alone" sera of individuals referred to the diagnostic laboratory without HCV antibodies. Direct sequencing of all PCR products confirmed the specificity of the PCR reactions and revealed the predominance of HBV genotype D. The data presented in this study suggest that detection of "anti-HBc alone" could reflect unrecognized "occult" HBV infection and that physicians should consider investigating such patients with HBV molecular tests. J. Med. Virol. 80:577,582, 2008. © 2008 Wiley-Liss, Inc. [source]


    Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 65

    JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003
    E Bellone
    Mutations in a gene encoding a novel protein of unknown function, the ganglioside-induced differentiation-associated protein 1 gene (GDAP1), are associated with one of the autosomal recessive forms of Charcot-Marie-Tooth disease (CMT4A). Mutations in GDAP1 can cause both axonal and demyelinating inherited peripheral neuropathies. The GDAP1 gene maps on chromosome 8q21.1, encompassing 13.9 kb of genomic DNA. The coding sequence is comprised of six exons. Little is known about the function of GDAP1. The mouse homologue Gdap1 is highly expressed in brain. Northern-blot analysis showed that GDAP1 is also expressed in peripheral nerves, both in neurons and in Schwann cells. A series of Italian patients with demyelinating (n = 42) and axonal (n = 39) peripheral neuropathy with possible recessive inheritance was screened for mutations in the GDAP1 gene. The entire coding region, including exon-intron boundaries, was examined by single strand conformation polymorphism (SSCP) and direct sequencing. All patients were negative for the 17p11.2 duplication and for mutations in the MPZ, GJB1, PMP22 and EGR2 genes. SSCP analysis showed a few electrophoretic variants, in the exon 1, exon 3 and exon 4, respectively. Direct sequencing demonstrated the presence of a common single nucleotide polymorphism in the exon 4 (c.507T > G) and a nucleotide substitution in the exon 3. The latter was found in four patients, belonging to three families, and was not detected in a series of normal subjects. Further studies are in progress to evaluate the possible role of this variant in the pathophysiology of the disease. This work was partially supported by grants MURST 2000 to F.A. and Ministero della Sanità to P.M. [source]


    Novel MPZ Mutation In A Sporadic CMT Patient

    JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2001
    E Bellone
    Mutations in the gene for the major structural protein component of peripheral nerve myelin, myelin protein zero (MPZ), are associated with some forms of hereditary neuropathies such as Charcot-Marie-Tooth disease type 1B (CMT1B), Dejerine-Sottas syndrome (DSS) and congenital hypomyelinating neuropathy (CHN). The common pathological characteristics of these allelic disorders are severe demyelination and remyelination of peripheral nerves. Recently, MPZ mutations were also found in patients with the axonal form of CMT neuropathy (CMT2). We studied a patient with negative familiar history and clinical and electrophysiological features of Charcot-Marie-Tooth disease: distal muscle weakness and atrophy, foot deformities (pes cavus), and severely reduced nerve conduction velocities in the motor and sensory nerves. The sural nerve biopsy showed marked loss of myelinated fibers, few onion bulbs, and a high percentage of fibers showing excessive myelin outfoldings. DNA analysis excluded CMT1A duplication by Southern blot and by pulsed field gel electrophoresis methods. SSCP analysis of all six exons of MPZ revealed a shift band in exon 2 in the patient's DNA. No such difference was detected in normal controls. Direct sequencing disclosed a G , A transition at nucleotide position 181. This base substitution predicts the replacement of aspartic acid with asparagine at codon 61. A mutation at the same codon (but different amino acid replacement) was recently identified in a family with the axonal type of CMT, in which the disease was autosomal dominantly inherited. This finding provides further confirmation of the role of MPZ gene in peripheral neuropathies and suggests that MPZ coding region mutations may account for a considerable number of CMT cases which do not involve DNA duplication on 17p11.2-p12. This research was partially supported by a MURST and an Ateneo grant to FA, by a Ministero della Sanità grant to PM. Our laboratory is a member of the European Charcot-Marie-Tooth Consortium co-ordinated by Prof. Christine Van Broeckhoven. [source]


    Performance of sequence analysis, INNO-LiPA line probe assays and AFFIGENE assays in the detection of hepatitis B virus polymerase and precore/core promoter mutations

    JOURNAL OF VIRAL HEPATITIS, Issue 6 2006
    A. Olivero
    Summary., In this study, we compare results obtained by sequences analysis and commercial kits in the detection of hepatitis B virus (HBV) polymerase and precore (PC) and core promoter mutations. A total of 23 serum samples from lamivudine treated patients were tested for polymerase mutations by direct sequencing, INNO-LiPA HBV DR and AFFIGENE HBV DE/3TC. Full concordance among the three assays was observed in 63% of the total analysed codons. Concordant results were obtained between sequencing and LiPA in 80%, between sequencing and AFFIGENE in 73% and between LiPA and AFFIGENE in 74% of all tested codons. All discrepancies were observed in mixed population samples in which AFFIGENE and LiPA detected additional viral variants not revealed by sequence. In two patients, with serial samples, LiPA detected earlier than sequence and AFFIGENE an emerging mutate strain. PC and core promoter viral variants were detected in 28 serum samples collected from 14 HBV inactive carriers and from 14 hepatitis B patients with chronic liver disease. Direct sequencing, INNO-LiPA HBV PreCore and AFFIGENE HBV MUTANT VL 19 showed fully coincident results in 88% of tested positions. These findings showed that all assays evaluated were sensitive and accurate tools to analyse HBV genomic variability. Sequence analysis is essential to study new emerging mutations as LiPA and AFFIGENE assays are more easily useful in clinical laboratories to detect the appearance of well-characterized HBV variants. [source]


    Distinct association of genetic variations of vascular endothelial growth factor, transforming growth factor-,, and fibroblast growth factor receptors with atopy and airway hyperresponsiveness

    ALLERGY, Issue 4 2008
    H.-K. Park
    Background:, Recent studies showed that high levels of transforming growth factor (TGF)-,1 in the airways reduced airway responsiveness, which was reversed in conditions of basic fibroblast growth factor (FGF2) deficiency, whereas high levels of vascular endothelial growth factor (VEGF) enhanced airway sensitization to allergens and airway hyperresponsiveness (AHR). Objective:, We investigated the effect of single-nucleotide polymorphisms (SNPs) in the VEGF, TGF-,1, and FGF2 receptors on the expression of atopy and AHR in the general population. Methods:, Atopy and AHR were evaluated in a cohort of 2055 children and adolescents. Direct sequencing was used to identify informative SNPs (minor allele frequency >5%) in the receptors of candidate genes. Tagging SNPs were scored using the high-throughput single-base pair extension method, and the statistical significance of these scores was assessed via haplotype analysis. Results:, Informative SNPs were identified for VEGF receptors 1 (Flt-1); TGF-, receptor 3 (TGFBR3); and FGR receptors 1, 2, and 4 (FGFR1, FGFR2, and FGFR4), and 13 tagging SNPs were scored in the cohort. Atopy was significantly associated with haplotypes of TGFBR3, FGFR1, and FGFR2. Meanwhile, AHR was significantly associated with haplotypes of Flt-1, FGFR1, and FGFR4. However, atopy was not associated with genetic variations of Flt-1 and FGFR4, whereas AHR not associated with TGFBR3 and FGFR2. Conclusion:, The expression of atopy and AHR is distinctly associated with genetic variations in VEGF, TGF-,1, and FGFR in the Korean population. [source]


    Mitochondrial DNA reveals multiple Northern Hemisphere introductions of Caprella mutica (Crustacea, Amphipoda)

    MOLECULAR ECOLOGY, Issue 5 2008
    GAIL V. ASHTON
    Abstract Caprella mutica (Crustacea, Amphipoda) has been widely introduced to non-native regions in the last 40 years. Its native habitat is sub-boreal northeast Asia, but in the Northern Hemisphere, it is now found on both coasts of North America, and North Atlantic coastlines of Europe. Direct sequencing of mitochondrial DNA (cytochrome c oxidase subunit I gene) was used to compare genetic variation in native and non-native populations of C. mutica. These data were used to investigate the invasion history of C. mutica and to test potential source populations in Japan. High diversity (31 haplotypes from 49 individuals), but no phylogeographical structure, was identified in four populations in the putative native range. In contrast, non-native populations showed reduced genetic diversity (7 haplotypes from 249 individuals) and informative phylogeographical structure. Grouping of C. mutica populations into native, east Pacific, and Atlantic groups explained the most among-region variation (59%). This indicates independent introduction pathways for C. mutica to the Pacific and Atlantic coasts of North America. Two dominant haplotypes were identified in eastern and western Atlantic coastal populations, indicating several dispersal routes within the Atlantic. The analysis indicated that several introductions from multiple sources were likely to be responsible for the observed global distribution of C. mutica, but the pathways were least well defined among the Atlantic populations. The four sampled populations of C. mutica in Japan could not be identified as the direct source of the non-native populations examined in this study. The high diversity within the Japan populations indicates that the native range needs to be assessed at a far greater scale, both within and among populations, to accurately assess the source of the global spread of C. mutica. [source]


    Chromosome 1p and 19q status and p53 and p16 expression patterns as prognostic indicators of oligodendroglial tumors: A clinicopathological study using fluorescence in situ hybridization

    NEUROPATHOLOGY, Issue 1 2007
    Yoon Kyung Jeon
    To verify the prognostic implications of the statuses of chromosome 1p and 19q and the expressions of p53, p16 and GFAP in oligodendrogliomas, we investigated these parameters and correlated the results with patient outcome. Twenty-seven cases of low-grade oligodendroglioma (LO) and 29 cases of anaplastic oligodendroglioma (AO) were analyzed by FISH for 1p and 19q status and by immunohistochemistry for p53, p16, and GFAP expression using a tissue microarray. Direct sequencing of the p53 gene was also performed. 1p deletion was observed in 39 of 56 patients (69.9%), and 19q deletion in 41 of 56 (73.2%). Combined loss of 1p and 19q was found in 38 of 56 (67.9%) and exhibited distinct concomitant deletion (P = 0.000). p53 overexpression was observed in 17 cases (30.3%), GFAP expression in 18 cases (32.1%), and p16 loss in 40 cases (74%) of oligodendrogliomas. The expressions of p53 and GFAP were more frequent in AO than in LO (P = 0.015 and 0.001). In contrast, p53 expression was more common in oligodendrogliomas with an intact 19q (P = 0.029), or an intact 1p (P = 0.071). Only five of 14 patients with p53 expression showed TP53 mutation, which was inversely correlated with 1p deletion (P = 0.036). Patients with combined loss of 1p and 19q exhibited better overall survival (P = 0.045). Patients with p53 expression without combined 1p and 19q loss showed poor overall survival (P < 0.000). However, TP53 mutation along with 1p and 19q status could not predict patient outcome. Patients with p16 loss without combined 1p and 9q loss showed poor overall survival (P = 0.011). Therefore, in oligodendrogliomas, the absence of the combined deletion of 1p and 19q and the aberrant expression of p53 or loss of p16 could be used as poor prognostic markers. [source]


    Mutations in the PAX9 gene in sporadic oligodontia

    ORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 3 2010
    E Pawlowska
    To cite this article: Pawlowska E, Janik-Papis K, Poplawski T, Blasiak J, Szczepanska J: Mutations in the PAX9 gene in sporadic oligodontia Orthod Craniofac Res 2010;13:142,152 Structured Abstract Authors,,, Pawlowska E, Janik-Papis K, Poplawski T, Blasiak J, Szczepanska J Objectives,,, Oligodontia, a congenital lack of six or more teeth, is often associated with mutations in the PAX9 gene; therefore, we searched for mutations in this gene. Design,,, In the present work, we sequenced fragments of the PAX9 gene in individuals with sporadic oligodontia. Next, we genotyped some mutations we found in patients with oligodontia and individuals without tooth agenesis. Setting and Sample Population,,, DNA sequencing was performed in the material isolated from peripheral blood lymphocytes of six unrelated patients with sporadic, non-syndromic oligodontia. These patients were selected based upon explorative cluster analysis. Genotyping was performed in 38 patients with oligodontia and 100 control individuals. Material and Methods,,, Direct sequencing and restriction fragment length polymorphism PCR were employed. Results,,, We detected two homozygotic substitutions, IVS2-109G>C and IVS2-54A>G, in intron 2 in three patients. Another homozygotic substitution in intron 2, IVS2-41A>G, was revealed in two patients. Two patients had an IVS3+40G>A homozygotic change in intron 3 and 4 patients displayed a 717C>T transition in exon 4 (silent mutation). One patient had a heterozygotic 718G>C transversion, resulting in a missense Ala240Pro substitution. We detected also several other intronic substitutions. Further genotyping of the IVS2-54A>G, IVS2-109G>C, and IVS2-41A>G mutations suggested that they can display polymorphic changes. Conclusion,,, The IVS2-54A>G, IVS2-109G>C, and IVS2-41A>G mutations of the PAX9 gene may represent polymorphism associated with sporadic oligodontia. [source]


    Challenges of Diagnosis of Long-QT Syndrome in Children

    PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2007
    EWA MORIC-JANISZEWSKA Ph.D.
    We describe the clinical and genetic characteristics of the family, in which the diagnosis of LQT1 had been made. The electrocardiogram (ECG) characteristics of this patient indicated the likelihood of LQTS1. Polymorphic ventricular extrasystolies and episodes of polymorphic non-sustained ventricular tachycardia were confirmed by Holter ECG monitoring. On the exertional electrocardiogram polymorphic ventricular tachycardia (torsade de pointes) was recorded. Direct sequencing of both DNA strands revealed the absence of mutations or polymorphisms in the KCNQ1, HERG, and SCN5A genes. [source]


    Variation analysis of ,3 -adrenergic receptor and melanocortin-4 receptor genes in childhood obesity

    PEDIATRICS INTERNATIONAL, Issue 2 2007
    TOMOE KINOSHITA
    Abstract Background: Decreased energy expenditure and increased food intake are principal causes for obesity. In the present study, genotypes of ,3 -adrenergic receptor (,3AR) and of melanocortin-4 receptor (MC4R), both of which are believed to have a close link to the cause of obesity, were analyzed and compared with phenotypes of childhood obesity. Methods: Thirty-five obese children with moderate to severe obesity were enrolled. Direct sequencing of the MC4R coding region and pinpoint-polymerase chain reaction were used to detect genomic variation in the ,3AR gene using peripheral blood-derived DNA. Results: Allele frequency of Trp64Arg variation in the ,3AR gene in the obese subjects was 0.16, which is comparable with that in the healthy general population in eastern Asia. Comparison of phenotypical characteristics did not show a significant difference between Trp/Trp and Trp/Arg subjects. It was notable that body height SD was significantly higher in the Trp/Trp than the Trp/Arg subjects (0.93 ± 1.0 SD vs 0.07 ± 1.3 SD, P= 0.03). Annual weight gains were far beyond a hypothetical fat gain in an Arg64 heterozygote with decreased energy consumption, suggesting increased food intake in childhood obesity. There was, however, no variation in the MC4R gene despite thorough sequencing of the entire coding region. Conclusions: The Trp64Arg variation in the ,3AR gene has no relationship to the degree or the incidence of childhood obesity. The majority of childhood obesity can be characterized as tall stature, more rapid weight gain than that expected by decreased energy expenditure. Further investigation is necessary in regard to the increased food intake as a major cause of childhood obesity. [source]


    "Mowat-Wilson" syndrome with and without Hirschsprung disease is a distinct, recognizable multiple congenital anomalies-mental retardation syndrome caused by mutations in the zinc finger homeo box 1B gene

    AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 3 2002
    Christiane Zweier
    Abstract Recently mutations in the gene ZFHX1B (SIP1) were shown in patients with "syndromic Hirschsprung disease" with mental retardation (MR) and multiple congenital anomalies (MCA), but it was unclear if Hirschsprung disease is an obligate symptom of these mutations and if the distinct facial phenotype delineated by Mowat et al. [1998: J Med Genet 35: 617,623] is specific for ZFHX1B mutations. In order to address these open questions we analyzed the ZFHX1B gene in five patients, three of whom had "syndromic Hirschsprung disease" two with and one without the facial phenotype described by Mowat et al. [1998], and two of whom had the distinct facial gestalt without Hirschsprung disease. Analyses of microsatellite markers and newly identified SNPs, and/or FISH with BACs from the ZFHX1B region excluded large deletions in all five patients. Direct sequencing demonstrated truncating ZFHX1B mutations in all four patients with the characteristic facial phenotype, but not in the patient with syndromic Hirschsprung disease without the distinct facial appearance. We demonstrate that there is a specific clinical entity with a recognizable facial gestalt, mental retardation and variable MCAs which we propose be called the "Mowat-Wilson syndrome." © 2002 Wiley-Liss, Inc. [source]


    Mutations in the first MyTH4 domain of MYO15A are a common cause of DFNB3 hearing loss

    THE LARYNGOSCOPE, Issue 4 2009
    A. Eliot Shearer BSc
    Abstract Objectives. To use clinical and genetic analyses to determine the mutation causing autosomal recessive nonsyndromic hearing loss (ARNSHL) segregating in two consanguineous Iranian families. Study Design. Family study. Methods. Members of each family received otologic and audiometric examination for the type and extent of hearing loss. Linkage mapping using Affymetrix 50K GeneChips and short tandem repeat (STRP) analysis localized the hearing loss in both families to the DFNB3 locus. Direct sequencing of the MYO15A gene was completed on affected members of both families. Results. Family L-3165 segregated a novel homozygous missense mutation (c.6371G>A) that results in a p.R2124Q amino acid substitution in the myosin XVa protein, while family L-896 segregated a novel homozygous missense (c.6555C>T) mutation resulting in a p.P2073S amino acid change. Conclusions. These are the first MYO15A mutations reported to cause DFNB3 sensorineural hearing loss in the Iranian population. Like other mutations located in the myosin tail homology 4 (MyTH4) domain, the p.R2124Q and p.P2073S mutations are predicted to disrupt the function of the myosin XVa protein, which is integral to the mechanosensory activity of hair cells in the inner ear. Laryngoscope, 2009 [source]


    A New De Novo Missense Mutation in Connexin 26 in a Sporadic Case of Nonsyndromic Deafness

    THE LARYNGOSCOPE, Issue 5 2007
    Paola Primignani PhD
    Abstract Objectives: Mutations in the GJB2 gene, encoding Connexin 26, can cause nonsyndromic recessive deafness or dominant hearing loss (HL) with or without keratoderma. The objective was to perform a molecular evaluation to establish the inherited pattern of deafness in the sporadic cases afferent to our center. Methods: The subject was a 2-year-old Italian girl with nonsyndromic early onset HL. We performed DNA sequencing of the GJB2 gene and deletion analysis of the GJB6 gene in all family members. Results: Direct sequencing of the gene showed a heterozygous C,G transition at nucleotide 172 resulting in a proline to alanine amino acid substitution at codon 58 (P58A). The analyses indicate that the P58A mutation appeared de novo in the proband with a possible dominant effect. Conclusions: This mutation occurs in the first extracellular domain (EC1), which seems to be very important for connexon-connexon interaction and for the control of voltage gating of the channel. The de novo occurrence of an EC1 mutation in a sporadic case of deafness is consistent with the assumption that P58A can cause dominant HL. [source]


    The bovine fatty acid binding protein 4 gene is significantly associated with marbling and subcutaneous fat depth in Wagyu x Limousin F2 crosses

    ANIMAL GENETICS, Issue 4 2006
    J. J. Michal
    Summary Fatty acid binding protein 4 (FABP4), which is expressed in adipose tissue, interacts with peroxisome proliferator-activated receptors and binds to hormone-sensitive lipase and therefore, plays an important role in lipid metabolism and homeostasis in adipocytes. The objective of this study was to investigate associations of the bovine FABP4 gene with fat deposition. Both cDNA and genomic DNA sequences of the bovine gene were retrieved from the public databases and aligned to determine its genomic organization. Primers targeting two regions of the FABP4 gene were designed: from nucleotides 5433,6106 and from nucleotides 7417,7868 (AAFC01136716). Direct sequencing of polymerase chain reaction (PCR) products on two DNA pools from high- and low-marbling animals revealed two single nucleotide polymorphisms (SNPs): AAFC01136716.1:g.7516G>C and g.7713G>C. The former SNP, detected by PCR-restriction fragment length polymorphism using restriction enzyme MspA1I, was genotyped on 246 F2 animals in a Waygu × Limousin F2 reference population. Statistical analysis showed that the FABP4 genotype significantly affected marbling score (P = 0.0398) and subcutaneous fat depth (P = 0.0246). The FABP4 gene falls into a suggestive/significant quantitative trait loci interval for beef marbling that was previously reported on bovine chromosome 14 in three other populations. [source]


    Genetic variability of Tomato spotted wilt virus in Australia and validation of real time RT-PCR for its detection in single and bulked leaf samples

    ANNALS OF APPLIED BIOLOGY, Issue 4 2005
    R G DIETZGEN
    Summary The potential for large-scale use of a sensitive real time reverse transcription polymerase chain reaction (RT-PCR) assay was evaluated for the detection of Tomato spotted wilt virus (TSWV) in single and bulked leaf samples by comparing its sensitivity with that of DAS-ELISA. Using total RNA extracted with RNeasy® or leaf soak methods, real time RT-PCR detected TSWV in all infected samples collected from 16 horticultural crop species (including flowers, herbs and vegetables), two arable crop species, and four weed species by both assays. In samples in which DAS-ELISA had previously detected TSWV, real time RT-PCR was effective at detecting it in leaf tissues of all 22 plant species tested at a wide range of concentrations. Bulk samples required more robust and extensive extraction methods with real time RT-PCR, but it generally detected one infected sample in 1000 uninfected ones. By contrast, ELISA was less sensitive when used to test bulked samples, once detecting up to 1 infected in 800 samples with pepper but never detecting more than 1 infected in 200 samples in tomato and lettuce. It was also less reliable than real time RT-PCR when used to test samples from parts of the leaf where the virus concentration was low. The genetic variability among Australian isolates of TSWV was small. Direct sequencing of a 587 bp region of the nucleoprotein gene (S RNA) of 29 isolates from diverse crops and geographical locations yielded a maximum of only 4.3% nucleotide sequence difference. Phylogenetic analysis revealed no obvious groupings of isolates according to geographic origin or host species. TSWV isolates, that break TSWV resistance genes in tomato or pepper did not differ significantly in the N gene region studied, indicating that a different region of the virus genome is responsible for this trait. [source]


    Disentangling the bindweeds: hybridization and taxonomic diversity in British Calystegia (Convolvulaceae)

    BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009
    JACQUELINE M. BROWN
    Calystegia is taxonomically complex. More than 65 taxa are currently recognized, but species circumscription is problematic, geographical intergradation between taxa is common and hybridization between species is known to occur. In this study, the nuclear ribosomal internal transcribed spacer 1 region (ITS1) was used to investigate the extent to which interspecific hybridization has contributed to the generation of taxonomic diversity in the C. sepium complex of the genus. Focusing principally on taxa that occur in Britain and their putative relatives, patterns of infra-individual ITS1 variation were examined by direct sequencing and cloning. Direct sequencing of the ITS region of 58 accessions representing 11 taxa and one hybrid revealed 22 variable positions that collectively defined 14 ribotypes. Diagnostic and invariant ribotypes lacking polymorphisms were found in C. sepium ssp. sepium, C. sepium ssp. limnophila, C. silvatica ssp. silvatica, C. pellita, C. pubescens and C. soldanella. Three ribotypes were recovered in C. sepium ssp. americana, two of which lacked polymorphisms, whereas the third exhibited two polymorphic sites. Calystegia sepium ssp. roseata, C. sepium ssp. spectabilis, C. silvatica ssp. disjuncta, C. pulchra and C. × howittiorum were each characterized by taxon-specific polymorphisms in the ITS1 region. In each case, the polymorphisms observed were consistent with the co-occurrence in the genome of nonpolymorphic ribotypes that were observed in other taxa. This observation is supported by cloning of the ITS region and is consistent with a hybrid origin for the taxa in which they occur. The hypotheses of hybridity proposed are further shown to be congruent with other data, notably morphology. This study suggests that taxonomic diversity within the C. sepium complex may have been promoted by hybridization. For at least some of the taxa investigated, it is at least possible that sympatry may have been achieved anthropogenically, through the introduction of taxa into cultivation. The processes revealed in this study may help to explain some of the taxonomic complexity observed in the genus more widely, although this remains to be tested. © 2009 The Natural History Museum, London, Botanical Journal of the Linnean Society, 2009, 160, 388,401. [source]


    A Japanese case of segmental Darier's disease caused by mosaicism for the ATP2A2 mutation

    BRITISH JOURNAL OF DERMATOLOGY, Issue 1 2003
    T. Wada
    Summary Darier's disease is an autosomal dominant skin disorder that is characterized by multiple keratotic papules, focal loss of adhesion and abnormal keratinization. Mutations in the ATP2A2 gene encoding sarco/endoplasmic reticulum calcium pumping ATPase type 2 have been identified as the molecular basis of Darier's disease. Segmental Darier's disease is a rare type of Darier's disease in which there is characteristic localization of the keratotic papules in a linear pattern following Blaschko's lines. In this study we examined ATP2A2 mutations in a Japanese patient with segmental Darier's disease. The samples from affected skin, unaffected skin and peripheral leucocytes were subjected to polymerase chain reaction (PCR). Direct sequencing of the PCR products was performed. Sequence analysis revealed that the patient had 160A,G substitution mutation which predicts I54V. This novel mutation was present in the affected skin, but not in the unaffected skin or peripheral leucocytes. This is the first report of segmental Darier's disease caused by mosaicism for an ATP2A2 mutation in Japan. [source]


    A novel beta-delta globin gene fusion, anti-Lepore Hong Kong, leads to overexpression of delta globin chain and a mild thalassaemia intermedia phenotype when co-inherited with ,0 -thalassaemia

    BRITISH JOURNAL OF HAEMATOLOGY, Issue 1 2007
    Chi-Chiu So
    Summary Anti-Lepore haemoglobins (Hb) are rare ,, fusion variants that arise from non-homologous crossover during meiosis, resulting in a ,,,,,, configuration. A novel anti-Lepore mutation (anti-Lepore Hong Kong) was found in two Chinese families with raised Hb A2. Direct sequencing revealed a crossover within a 54-bp region spanning the junction of cap site (CAP) and exon 1, which predicted the production of normal , -globin. Determination of ,/, -mRNA ratios by quantitative real-time polymerase chain reaction demonstrated downregulation of the , gene in cis due to the interposed ,, fusion gene. Although heterozygotes have normal red cell indices and are clinically silent, compound heterozygotes with ,0 mutation in trans produce a mild thalassaemia intermedia phenotype with a markedly raised Hb A2 level that may mimic clinically mild Hb E- ,+ -thalassaemia. Awareness of the presence of anti-Lepore Hong Kong will help to resolve diagnostic problems in regions with significant prevalence of globin disorders. [source]


    Cutaneous abscess by Trichosporon asahii developing on a steroid injection site in a healthy adult

    CLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 4 2006
    S. J. Yun
    Summary We report a rare case of cutaneous abscess by Trichosporon asahii in an immunocompetent adult. A 31-year-old Korean woman presented to our hospital with a cutaneous abscess. She had received an intralesional steroid injection 4 months earlier on the site of a hypertrophic scar. Direct sequencing of the intergenic spacer regions of the rRNA genes identified T. asahii. The decreased local immunity after the steroid injection might have triggered the infection by T. asahii. A cutaneous abscess formation by T. asahii in an immunocompetent patient is an unusual cutaneous finding that to our knowledge has not been reported previously. The local immune reaction of the skin is important for the prevention of Trichosporon infection. [source]


    A new mutation in the linker 12 domain of keratin 5 in a Chinese family with Weber,Cockayne epidermolysis bullosa simplex

    CLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 5 2004
    J.-G. Li
    Summary A previously undescribed missense mutation was detected in the L12 domain of keratin 5 (K5) in a Chinese family with Weber,Cockayne epidermolysis bullosa simplex. Direct sequencing of the PCR products identified a single base substitution (983A,G) that changes the aspartic acid residue at codon 328 to glycine in all affected family members, while no mutation was observed either in the healthy individual or 50 unrelated control samples. Asp328 of K5 is remarkably conserved among all type II keratins. D328G is the fourth mutation found to affect this residue in K5-related epidermolysis bullosa simplex, indicating the importance of Asp328 for K5 structure and the dramatic effect that fine changes can have on keratin intermediate filament integrity. [source]


    CYR61 polymorphisms are associated with plasma HDL-cholesterol levels in obese individuals

    CLINICAL GENETICS, Issue 3 2007
    L Bouchard
    We have recently characterized the transcriptome of the omental adipose tissue of non-diabetic, obese men with and without the metabolic syndrome (MS). The cysteine-rich protein 61 (CYR61) is one of the most differentially expressed genes between the groups and has been selected for a detailed molecular investigation. Direct sequencing of complete CYR61 gene revealed five polymorphisms with minor allele frequency >5% in the promoter region (rs3753794, rs3753793 and rs2297140), intron 1 (rs2297141) and intron 2 (IVS2+50). Chi-square test and logistic regression were applied to test for association between CYR61 polymorphisms and the individual MS components in a cohort of 697 obese individuals. In men and women, rs3753794 and rs3753793 (r2 = 0.77) were associated plasma HDL-cholesterol levels (p = 0.016 and p = 0.008). Carriers of the A allele for rs3753794 were more likely to have high plasma HDL-cholesterol levels (1.50-fold; p = 0.016), as compared with G/G homozygotes and the A/A homozygotes for rs3753793 were more likely to exhibit low plasma HDL-cholesterol levels (1.56-fold; p = 0.008), as compared with C/C homozygotes. Furthermore, an association between IVS2+50 polymorphism and HDL-cholesterol was found in women and in men analyzed separately (p = 0.002 and p = 0.038, respectively). These results suggest that CYR61 is a promising candidate gene for lipoprotein/lipid perturbations. [source]


    DNA sequence analysis of interlocus recombination between the human T-cell receptor gamma variable (GV) and beta diversity-joining (BD/BJ) sequences on chromosome 7 (inversion 7)

    ENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 2 2002
    Scott W. Ballinger
    Abstract V(D)J recombinase-mediated recombination between the T-cell receptor (TCR) gamma variable (GV) genes at chromosome 7p15 and the TCR beta joining (BJ) genes at 7q35 leads to the formation of a hybrid TCR gene. These TCR gamma/beta interlocus rearrangements occur at classic V(D)J recombination signal sequences (RSS) and, because the loci are in an inverted orientation, result in inversion events that are detectable in the chromosome structure as inv(7)(p15;q35). Similar rearrangements involving oncogenes and either TCR or immunoglobulin genes mediated by the V(D)J recombinase are found in lymphoid malignancies. Oligonucleotide primers that allow polymerase chain reaction (PCR) amplification across the inv(7) genomic recombination junction sequence have been described. Southern blot analysis has been primarily used to confirm the GV/BJ hybrid nature of the product, with limited information on the DNA sequence of these recombinations. We have modified this PCR method using total genomic DNA from the mononuclear cells in peripheral blood samples to increase specificity and to allow direct sequencing of the translocation junction that results from the recombination between the GV1 and BJ1 families of TCR genes in 25 examples from 11 individuals (three adults, one child, six newborns, and one ataxia telangiectasia (AT) patient). We focused on samples from newborns based on previous studies indicating that the predominant hypoxanthine-guanine phosphoribosyl transferase (HPRT) mutations in newborns are V(D)J recombinase-mediated deletion events and that the frequency of these mutations decreases with increasing age. Although the dilution series-based PCR assay utilized does not yield sharply defined quantitative endpoints, results of this study strongly suggest that inv(7) recombinations in newborns occur at equal or lower frequencies than those seen in adults. Consistent with the PCR primer pairs, all sequenced products contain a GV1 and a BJ1 segment and most also contain a BD1 segment. GV1s2 and 1s4 were the most frequently found GV1 genes (8 and 9 examples, respectively) and BJ1s5 and 1s6 were the most frequently found BJ1 genes (9 and 10 examples, respectively). These results demonstrate the effectiveness of this methodology for assessing GV/BJ interlocus rearrangements mediated by V(D)J recombinase. Environ. Mol. Mutagen. 40:85,92, 2002. © 2002 Wiley-Liss, Inc. [source]


    A New Chrna4 Mutation with Low Penetrance in Nocturnal Frontal Lobe Epilepsy

    EPILEPSIA, Issue 7 2003
    Tobias Leniger
    Summary: Purpose: To identify and characterize the mutation(s) causing nocturnal frontal lobe epilepsy in a German extended family. Methods: Neuronal nicotinic acetylcholine receptor (nAChR) subunit genes were screened by direct sequencing. Once a CHRNA4 mutation was identified, its biophysical and pharmacologic properties were characterized by expression experiments in Xenopus oocytes. Results: We report a new CHRNA4 mutation, causing a ,4-T265I amino acid exchange at the extracellular end of the second transmembrane domain (TM). Functional studies of ,4-T265I revealed an increased ACh sensitivity of the mutated receptors. ,4-T265I is associated with an unusual low penetrance of the epilepsy phenotype. Sequencing of the TM1-TM3 parts of the 1 known nAChR subunits did not support a two-locus model involving a second nAChR sequence variation. Conclusions: nAChR mutations found in familial epilepsy are not always associated with an autosomal dominant mode of inheritance. ,4-T265I is the first nAChR allele showing a markedly reduced penetrance consistent with a major gene effect. The low penetrance of the mutation is probably caused by unknown genetic or environmental factors or both. [source]