1.Novel mitochondrial 16S rRNA mutation, 3200T-->C, associated with adult-onset type 2 diabetes.
Tao YANG ; Ching-Wan LAM ; Man-Wo TSANG ; Sui-Fan TONG ; Grace Y W KAM ; Lisa Y S CHAN ; Priscilla M K POON ; Xiangqian WU ; Chi-Pu PANG
Chinese Medical Journal 2002;115(5):753-758
OBJECTIVETo investigate the role of a potential diabetes-related mitochondrial region, which includes two previously reported mutations, 3243A-->G and 3316G-->A, in Chinese patients with adult-onset type 2 diabetes.
METHODSA total of 277 patients and 241 normal subjects were recruited for the study. Mitochondrial nt 3116 - 3353, which spans the 16S rRNA, tRNA(leu(UUR)) and the NADH dehydrogenase 1 gene, were detected using polymerase chain reaction (PCR), direct DNA sequencing, PCR-restriction fragment length polymorphism and allele-specific PCR. Variants were analyzed by two-tailed Fisher exact test. The function of the variants in 16S rRNA were predicted for minimal free energy secondary structures by RNA folding software mfold version 3.
RESULTSFour homoplasmic nucleotide substitutions were observed, 3200T-->C, 3206C-->T, 3290T-->C and 3316G-->A. Only the 3200T-->C mutation is present in the diabetic population and absent in the control population. No statistically significant associations were found between the other three variants and type 2 diabetes. The 3200T-->C and 3206C-->T nucleotide substitutions located in 16S rRNA are novel variants. The 3200T-->C caused a great alteration in the minimal free energy secondary structure model while the 3206C-->T altered normal 16S rRNA structure little.
CONCLUSIONSThe results suggest that the 3200T-->C mutation is linked to the development of type 2 diabetes, but that the other observed mutations are neutral. In contrast to the Japanese studies, the 3316G-->A does not appear to be related to type 2 diabetes.
Age of Onset ; Aged ; Alleles ; Base Sequence ; DNA Mutational Analysis ; DNA, Mitochondrial ; chemistry ; genetics ; Diabetes Mellitus, Type 2 ; genetics ; Humans ; Middle Aged ; Models, Molecular ; Nucleic Acid Conformation ; Point Mutation ; Polymerase Chain Reaction ; methods ; Polymorphism, Restriction Fragment Length ; RNA, Ribosomal, 16S ; chemistry ; genetics
4.Molecular basis of von Hippel-Lindau syndrome in Chinese patients.
Wai-Kwan SIU ; Ronald Ching-Wan MA ; Ching-Wan LAM ; Chloe Miu MAK ; Yuet-Ping YUEN ; Fai-Man Ivan LO ; Kin-Wah CHAN ; Siu-Fung LAM ; Siu-Cheung LING ; Sui-Fan TONG ; Wing-Yee SO ; Chun-Chung CHOW ; Mary Hoi-Yin TANG ; Wing-Hung TAM ; Albert Yan-Wo CHAN
Chinese Medical Journal 2011;124(2):237-241
BACKGROUNDVon Hippel-Lindau (VHL) syndrome is an autosomal dominant familial cancer syndrome predisposing the affected individuals to multiple tumours in various organs. The genetic basis of VHL in Southern Chinese is largely unknown. In this study, we characterized the mutation spectrum of VHL in nine unrelated Southern Chinese families.
METHODSNine probands with clinical features of VHL, two symptomatic and eight asymptomatic family members were included in this study. Prenatal diagnosis was performed twice for one proband. Two probands had only isolated bilateral phaeochromocytoma. The VHL gene was screened for mutations by polymerase chain reaction, direct sequencing and multiplex ligation-dependent probe amplification (MLPA).
RESULTSThe nine probands and the two symptomatic family members carried heterozygous germline mutations. Eight different VHL mutations were identified in the nine probands. One splicing mutation, NM_000551.2: c.463+1G > T, was novel. The other seven VHL mutations, c.233A > G [p.Asn78Ser], c.239G > T [p.Ser80Ile], c.319C > G [p.Arg107Gly], c.481C > T [p.Arg161X], c.482G > A [p.Arg161Gln], c.499C > T [p.Arg167Trp] and an exon 2 deletion, had been previously reported. Three asymptomatic family members were positive for the mutation and the other five tested negative. In prenatal diagnosis, the fetuses were positive for the mutation.
CONCLUSIONSGenetic analysis could accurately confirm VHL syndrome in patients with isolated tumours such as sporadic phaeochromocytoma or epididymal papillary cystadenoma. Mutation detection in asymptomatic family members allows regular tumour surveillance and early intervention to improve their prognosis. DNA-based diagnosis can have an important impact on clinical management for VHL families.
Asian Continental Ancestry Group ; DNA Mutational Analysis ; Humans ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Von Hippel-Lindau Tumor Suppressor Protein ; genetics ; von Hippel-Lindau Disease ; genetics
5.Genetic characterization analysis on epidemic rubella virus strains isolated in Liaoning from 2007 to 2012.
Yan WANG ; Yan MA ; Xiao-Ting XU ; Xue-Song FAN ; Qian LIN ; Dan SUI ; Ye YIN ; Feng-Tong WU ; Bai-Ling PAN ; Guang-Yuan LIU ; Ji-Jian WANG ; Yue HAN ; Jun-Qiao GUO ; Zhuo ZHAO
Chinese Journal of Virology 2013;29(6):589-595
To analyze the genetic characterization of epidemic rubella virus strains isolated in Liaoning from 2007-2012, a total of 145 rubella virus strains were isolated using Vero/Slam cell line from the patients' throat swabs during rubella outbreaks and sporadics cases in Liaoning Province from 2007 to 2012. Fragments of 945 nucleotides containing 1E gene from 145 rubella virus isolates were amplified by RT-PCR, the PCR products were sequenced and analyzed. Based on the 739 nucleotides of 1E gene, the phylogenetic trees were constructed with 32 WHO rubella reference strains of 13 genotypes downloaded from GenBank and 145 rubella virus strains. The results showed that the 145 rubella virus strains in 2007 -2012 belonged to genotype 1E, nucleotide acids and amino acids similarities were 97.2%-100.0% and 97.6%-100.0%, respectively. Compared to the 1E reference strains(Rvi/ Dezhou.CHN/02, RVi/MYS/01), the nucleotide acids and amino acids similarities were 96.6%-99.2% and 98.2%-100.0%, respectively except for one amino acid change (Val246-Ala246) of RVi/Shenyang. Liaoning. CHN/13.11/13, and Asp262-Asn262 of RVi/Shenyang. Liaoning. CHN/13.11/4 and RVi/Liaoyang. Liaoning. CHN/26. 11/2. there had no change found in the important antigenic epitope sites, the hemagglutination inhibition and neutralization epitopes of the other rubella viruses. All the 145 strains isolated had the same amino acid change (Leu338--Phe338) in E1 protein. These findings suggested that genotype 1E of rubella virus was the predominant genotype in Liaoning province. the rubella prevailed in recent six years was mainly caused by rubella viruses genotype 1E with multi-transmission routes.
Amino Acid Sequence
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China
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epidemiology
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Epidemics
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Genotype
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Humans
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Molecular Sequence Data
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Phylogeny
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Rubella
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epidemiology
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virology
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Rubella virus
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classification
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genetics
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isolation & purification
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Sequence Alignment
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Viral Envelope Proteins
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chemistry
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genetics