Genotype and phenotype analysis of two monozygotic twins with neurofibromatosis type 1 but inconsistent congenital pseudarthrosis / 中华骨科杂志

Objective:To compare the genotypes and phenotypes between the monozygotic twins via whole genome sequencing to further clarify the autosomal dominant inherited neurofibromatosis type 1 (NF1) variants related to congenital pseudarthrosis (CP).Methods:According to the diagnostic criteria of congenital tibial pseudarthrosis and the clinical diagnostic criteria of NF1, two pairs of monozygotic twins with NF1 were included. Both were female and only one of each pair had congenital pseudarthrosis. The other did not have congenital pseudarthrosis. Whole genome sequencing was performed using the peripheral blood of the two pairs of monozygotic twins. Customized bioinformatics analysis was then performed to identify single nucleotide variants (SNVs), short insertion deletion variants (InDel), copy number variants (CNVs), and structural variants (SVs). Classified the variants according to the American College of Medical Genetics and Genomics (ACMG) and ClinGen criteria. The germline variants within the monozygotic twins were compared to identify the CP patients' unique variants. The shared pathogenic or likely pathogenic germline variants between the unique variants in the CP patients from the twins were also analyzed. Further, the identified disease-causing variants were validated by Sanger sequencing in the family of the twins and their parents. Finally, the genotypes and phenotypes regarding the pathogenic variants of the NF1 gene among the twins were characterized. Results:Both the two monozygotic twins were identified pathogenic variants in the NF1 gene. One with c.3047_3048del (p.Cys1016SerfsTer4), and the other with c.4267A>G (p.Lys1423Glu). By Sanger sequencing validation in family quads, the two CP patients and their siblings harbored de novo heterozygous variants of the NF1 gene. In addition to the NF1 gene, no other genes were identified pathogenic or likely pathogenic variants uniquely in the CP patients compared with their twin sisters, as well as SVs and CNVs. In addition, by analyzing the rare and damaging variants in the two CP patients from the two twins, they had no overlapping genes against the SNVs, InDels, SVs, or CNVs. Conclusion:Whole genome sequencing revealed that both the two monozygotic twins with NF1 were detected pathogenic variants of gene NF1. No other pathogenic variants specific to the CP patients among the twins were identified. The two CP patients shared no other common genes from the detected likely pathogenic variants.

Association of NLRP3 gene single nucleotide polymorphisms with metabolic syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the association of single nucleotide polymorphisms (SNPs) of NLRP3 gene with metabolic syndrome (MetS).</p><p><b>METHODS</b>A total of 885 subjects including 410 MetS patients and 475 healthy controls were recruited. MetS was defined based on the National Cholesterol Education Program in Adult Treatment Panel III criteria. Two common SNPs of the NLRP3 gene, rs10754558 and rs4612666, were detected using polymerase chain reaction-restriction fragment length polymorphism method.</p><p><b>RESULTS</b>The frequencies of G allele and GG genotype of the NLRP3 rs10754558 in the MetS group were significantly higher than those of the control group. Logistic regression analysis showed that the GG genotype (OR=2.223, 95%CI: 1.296-6.924, P=0.00034) and G allele (OR=1.440, 95%CI: 1.189-4.063, P=0.00028) were associated with increased risk of MetS. NLRP3 rs10754558 GG genotype was associated with higher level of insulin resistance and visceral adiposity index. No association of NLRP3 rs4612666 SNPs with susceptibility to MetS was identified in this population.</p><p><b>CONCLUSION</b>NLRP3 gene rs10754558 polymorphisms are associated with increased risk of MetS. The G allele and genotype GG are risk factors for MetS.</p>

Association study of disrupted in schizophrenia 1 gene polymorphisms with autism in Chinese Han children / 中华实用儿科临床杂志

Objective To investigate the relationship between the single nucleotide polymorphisms(SNPs) of disrupted in schizophrenia 1 (DISC1) gene and autism in Chinese Han children.Methods Genome-wide SNP genotyping was performed by using Illumina HumanHap CNV370-Duo Chip in 278 autistic trios,157 autistic individuals and 435 healthy controls.Genotype data of SNPs within DISC1 gene were selected.The association between these SNPs loci and autism was analyzed through case-control association analysis and family-based transmission disequilibrium test.Results Fifty-two SNPs were involved for further analysis.1.Case-control association analysis showed that 6 SNPs (rs4658939,rs2793093,rs10495309,rs2492367,rs1 1122362,rs1073179) and 7 haplotypes (AGAAAG constructed with rs823163-rs823161-rs4658933-rs1417585-rs10864693-rs6541281,GGG and AAA constructed with rs4658939-rs2793093-rs10495309,GG and AG constructed with rs2492367-rs12046794,GAA constructed with rs9432040-rs2356606-rs1 1122362 and GG constructed with rs9431714-rs1073179) had significant differences between autistic patients and controls(x2 =4.704,4.915,5.568,8.087,4.043,5.183,5.369,5.295,4.440,5.304,7.615,4.018,4.811,P =0.030,0.027,0.018,0.005,0.044,0.023,0.021,0.021,0.035,0.021,0.006,0.045,0.028).2.In the transmission disequilibrium test analysis,2 SNPs (rs4658945,rs11122362) and 2 haplotypes (AG constructed with rs10495310-rs4658945,GAA constructed with rs9432040-rs2356606-rs11122362) showed significant transmission disequilibrium(x2=4.445,5.400,3.973,5.126,P =0.035,0.020,0.046,0.024).Conclusions The polymorphism of rs11122362 and GAA haplotype constructed with rs9432040-rs2356606-rs11122362 are associated with autism,and DISC1 gene is a susceptibility gene for autism in Chinese Han children.

Identification of a known GJB6 mutation in an autosomal dominant inherited Chinese family with hidrotic ectodermal dysplasia / 中南大学学报(医学版)

Objective:Mutation in the gap junction beta 6 (GJB6) gene has been reported to be associated with an autosomal dominant disorder hidrotic ectodermal dysplasia (HED), characterized by congenital nail clubbing, alopecia and palmoplantar keratoderma. The aim of this study is to investigate relationship between genetic mutation in GJB6 and HED in an affected Chinese family. Methods:We selected a Chinese HED family consisting of a total of 17 individuals including 8 HED patients (5 males and 3 females). The whole coding region of GJB6 was amplified by polymerase chain reaction and sequenced. Results:Sequence analysis identified a heterozygous missense mutation c.31G>A (p.G11R) in GJB6 gene of affected individuals, but not in healthy individuals. Conclusion:A c.31G>A (p.G11R) missense mutation in GJB6 gene is the genotypic characteristic for HED in Chinese population.

Genetics of autism spectrum disorders / 中南大学学报(医学版)

Autism is a group of etiology and clinical heterogeneous neurodevelopmental disorders with an onset before 3 years old. It has 3 core characteristics: deficits in verbal communication; impairment of social interaction; restricted interests and repetitive behaviors. The incidence is increasing over time worldwide. Twin and family studies have demonstrated that autism has a high heritability (>90%). Although certain progress of autism genetic study has been made in the last decades and several autism susceptibility genes and loci have been identified, there are still about 70%-80% of patients for whom an autism-related genetic change cannot be identified.

Genetics of autism spectrum disorders / 中南大学学报(医学版)

Autism is a group of etiology and clinical heterogeneous neurodevelopmental disorders with an onset before 3 years old.It has 3 core characteristics:deficits in verbal communication;impairment of social interaction; restricted interests and repetitive behaviors.The incidence is increasing over time worldwide.Twin and family studies have demonstrated that autism has a high heritability ( ＞ 90％ ).Although certain progress of autism genetic study has been made in the last decades and several autism susceptibility genes and loci have been identified,there are still about 70％ -80％ of patients for whom an autism-related genetic change cannot be identified.

Genetic mapping and mutation analysis in a family with paroxysmal kinesigenic dystonia / 中华神经科杂志

Objective To study the clinical characteristics and genetic cause of a Chinese family affected with paroxysmal kinesigenic dystonia(PKD).Methods The detailed clinical data and the blood samples of the affected patients with PKD and their relatives were collected.After genomic DNA was extracted from blood leukocytes,target linkage analysis Was performed using multiplex PCR by microsatellite marker's located in the reported critical region on chromosome 16.All exons and flanking regions of SCNN1G and ITGAL genes were amplified by PCR-sequence.Results In this three-generation 12 member family,5 individuals have been diagnosed as PKD.Target linkage analysis suggested the disease gene linked to chromosome 16.between D16S3396 and D16S3057 with two-point LOD score of 1.47 at recombination fraction(θ)=0.0.All affected individuals shared a common haplotype which co-segregated with the phenotype.Except for 8 reported SNPs,no pathologic sequence variants were found in candidate genes SCNN1G and ITGAL.Conclusions The studied family is genetically linked to the reported critical locus of PKD on chromosome 16.SCNN1G and ITGAL were ruled out as the causative genes for the studied pedigree.Further genetic analysis in this family may reveal new genetic cause responsible for PKD.

GJB2 (connexin 26) gene mutation screen in patients with nonsydromic hearing loss in Hunan / 中南大学学报(医学版)

OBJECTIVE@#To identify the genetic characteristics in patients with nonsydromic hearing loss (NSHL) in Hunan province, to determine the prevalence and spectrum of mutations in GJB2 gene, and to explore the pathogenic mechanism.@*METHODS@#A total of 140 sporadic patients with NSHL were enrolled after clinical examination. Molecular studies were performed by amplifing the coding region of GJB2 gene, purifying the PCR products, and sequencing directly. Sequences were analysed by DNAStar software to determine GJB2 mutations in the patients. Special method was designed to confirm the unreported mutation.@*RESULTS@#We detected GJB2 mutation in 56 out of the 140 patients (40%, 56/140). Both of the 2 alleles were mutated in 29 patients and 1 allele in the other 27 patients, and the rate of allele mutation was 30.4%(85/280). Ten variations were detected, including 7 mutations and 3 polymorphisms. The deaf-causing mutations were nonsense mutation c.139G>T; frameshift mutation c.235delC and c.176-191del16; and missense mutation c.109G>A, c.344T>G, c.550C>T and c.571T>C. The unreported missense mutation was c.344T>G. The c.235delC mutation was the most prevalent mutation found in the 27 patients (19.3%, 27/140). The frequency of c.109G>A mutation was next to c.235delC found in 25 patients (17.9%, 25/140).@*CONCLUSION@#GJB2 mutation is a major cause for NSHL. The most common-spot in Chinese patients with NSHL is c.235delC. The unreported missense mutation is c.344T>G.

Localization of the disease-causing gene coding for hereditary palmoplantar keratoderma / 基础医学与临床

Objective To identify a locus at chromosome coding for hereditary palmoplantar keratoderma of three Chinese pedigrees.Methods The genome scan was conducted with microsatellite markers on chromosome 12(D12S85、D12S368、D12S83、D12S345)and 17(D17S1868、D17S787、D17S1857、D17S798、D17S944、D17S949)respectively on the ABI 3100 Genetic Analyzer(Applied Biosystems).Two-point LOD score was calculated.Results The maximum two-point LOD score 6.59 and 5.96 at ?=0.1 were obtained at D17S1868 and D17S787 on chromosome 17q12～q21.It is an evidence of linkage between this disease and KRT9 which has been mapped within the region.Conclusion There is a locus responsible for this disease on chromosome 17q12～q21.

ATM gene mutations in Chinese patients with ataxia telangiectasia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the mutation characteristics of ATM gene in Chinese patients with ataxia-telangiectasia (AT).</p><p><b>METHODS</b>Mutation of ATM gene was screened by polymerase chain reaction, reverse transcription-polymerase chain reaction, polyacrylamide gel electrophoresis combined with DNA direct sequencing in two Chinese AT patients.</p><p><b>RESULTS</b>A missense mutation of 1346(G>C) in exon 11, which was a homozygotic mutation, was identified in one patient; a nonsense mutation of 610 (G>T) in exon 6 combined with a missense mutation of 6679 (C>T) in exon 47, which was a compound heterozygotic mutation, were identified in the other patient. They were co-segregated with the disease and were localized within the functional domain of ATM gene.</p><p><b>CONCLUSION</b>Totally three novel ATM gene mutations were identified in two Chinese AT patients.</p>

Studies on PANK2 gene mutations in Chinese patients with Hallervorden-Spatz syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study pantothenate kinase 2 (PANK2) gene mutations in Chinese patients with Hallervorden-Spatz syndrome (HSS).</p><p><b>METHODS</b>PANK2 gene mutations were detected by PCR, DNA sequence analyses, restriction enzyme digestion and PCR-single strand conformation polymorphism in 5 patients, 3 unaffected family members and 51 unrelated healthy persons.</p><p><b>RESULTS</b>Novel compound heterozygous PANK2 gene mutations, A803G and T1172A, in exons 3 and 5, respectively, were found in one patient. At the same time, 3 types of single nucleotide polymorphisms, -38 t>a in 5'-UTR, IVS1+42 c>a and G77C in exon 1, were confirmed; among them, -38 t>a, IVS1+42 c>a, were first reported.</p><p><b>CONCLUSION</b>PANK2 gene mutations can cause HSS in Chinese patients.</p>