A novel method for hepatitis C virus genotyping using RT-PCR reverse dot blot hybridization technique / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop a rapid and specific method for hepatitis C virus ( HCV) genotyping using reverse dot blot hybridization technique and investigate the distribution of HCV genotypes and subtypes in Guangdong.</p><p><b>METHODS</b>The primers and the probes targeting the 5'untranslated region (5'UTR) and core region of HCV genotypes 1b, 2a, 3a, 3b and 6a were designed, and the RT-PCR reverse dot blot hybridization (PCR-RDH) method for HCV genotyping was established. A total of 115 patients with hepatitis C were genotyped using this method, and 38 of them were also genotyped by sequencing and phylogenetic analysis to evaluate the accuracy and specificity of the method.</p><p><b>RESULTS</b>Of the 115 patients, 111 were successfully genotyped to be 1b, 2a, 3a, 3b, 6a and mix-infection of 1b/2a at frequencies of 56.8%, 8.1 %, 3.6%, 5.4%, 25.2% and 0.9% respectively, and all the 15 healthy control samples showed negative results. The accuracy and reliability of the genotyping method of PCR-RDH was confirmed in 38 cases by amplification of HCV core and NS5B regions followed by DNA sequencing and phylogenetic analysis.</p><p><b>CONCLUSION</b>This method for HCV genotyping, with high reliability and specificity, is suitable for clinical and epidemiological investigations. The prevalence of HCV genotypes 1b and 2a decreases while 1b remains the dominant genotype in Guangdong, where the prevalence of 6a significantly increases as compared with that 10 years ago.</p>

Relationship between apolipoprotein E, D10S1225 polymorphisms and late-onset Alzheimer's disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>There were some papers published in the Jonrnal of Science, December 2000 suggesting that one or more important susceptibility genes for late onset Alzheimer's disease (LOAD) were located on the long arm of chromosome 10. Linkage analysis showed maximum lod score close to D10S1225 loci, which indicated the loci might contribute to the etiology of Alzheimer's disease (AD).</p><p><b>METHODS</b>Fifty-nine LOAD patients and 107 controls were recruited. Apolipoprotein E (ApoE) genotypes were determined by reverse dot blotting hybridization assay. The D10S1225 was genotyped by 12% nondenaturing polyacrylamide gels electrophoresis and analyzed by silver staining. Statistical analysis was used to compare genotype and allele distributions between LOAD group and control group for ApoE and D10S1225 polymorphisms.</p><p><b>RESULTS</b>ApoE epsilon 4 was significantly higher in LOAD group in comparison with the control group (chi(2) = 6.530, P = 0.011). Seven different alleles of D10S1225 have been identified. The length of these gene fragments were 178 bp, 181 bp, 184 bp, 187 bp, 190 bp, 193 bp, and 196 bp, respectively. A total of 21 different genotypes were observed. There was no relationship between D10S1225 polymorphism and LOAD (chi(2) = 4.488, P > 0.05). Conclusion This study suggests that ApoE epsilon 4 is a risk factor for LOAD, however, the results indicated that there is not any possible linkage for disequilibria with a nearby AD risk gene near D10S1225.</p>