Power divergence test statistics for testing Hardy–Weinberg equilibrium

The Hardy–Weinberg equilibrium (HWE) model states that allele and genotype frequencies in a population will remain constant for generations in the absence of evolutionary effects. A goodness-of-fit test can be used to test if a population is significantly different from the expectations of HWE. Pearson statistics are commonly used in goodness-of-fit tests for testing the HWE. In this paper, a simulation study is carried out to evaluate the performance of power divergence statistics under different sample sizes, effect sizes and minor allele frequencies. A real genotype dataset is also analysed to compare the results of several power divergence test statistics.

Hepatitis C virus genotype distribution in Southern China during 2015-2016 / 中华传染病杂志

Objective To investigate the current distribution of hepatitis C virus (HCV) genotype in Southern China and to understand the HCV transmission and to infer its transmitting trend.Methods The HCV gene subtypes of 3 524 specimens from Southern China were detected and analyzed by polyonerase chain reaction (PCR)-fluorescence probe method or sequencing.The regular nested PCR and sequencing were used for the phylogenetic tree analysis when the fluorescence PCR inefficiently identifying virus isolates.Results Among 3 524 specimens,there were 2 922 cases from Guangdong,78 cases from Fujian,152 cases from Hainan and 372 cases from Guangxi.Genotype 1b comprised the majority (1 808/ 3 524,51.3％),followed by genotype 6a (925/3 524,26.2％),2a (298/3 524,8.46％),3a (246/ 3 524,6.98％),3b (200/3 524,5.68％) and 1a (27/3 524,0.77％).In addition,1 case wasgenotype 6e,1 case was genotype 6q,1 case was genotype 6r,3 case were genotype 6w,2 case were genotype 6xa,2 case were genotype 6n,and 1 case was genotype 6 with unclassified subtype.The genotype 1b accounted for the majority in most areas of 21 cities and counties in Guangdong Province,followed by genotype 6a.But in some areas,the major genotype was genotype 6a,followed by 1b.Genotype 4,genotype 5 and genotype 7 were not found in this study.Conclusions In the past two years,genotype 1b and 6a are still the epidemic genotypes in Guangdong,Guangxi and Hainan provinces.However,genotype 6a has replaced 1b as the dominant one in some areas in Guangdong Province.The distributions of HCV genotypes do not change significantly in Guangxi and Fujian provinces.

Chronic hepatitis C virus in the state of Piauí, northeastern Brazil

Knowledge of genotype distribution of hepatitis C virus (HCV) has clinical importance due to genotype 1 lower response to treatment compared with genotypes 2 and 3. The goal of this survey was to describe clinical and laboratorial profiles of patients with chronic hepatitis C (CHC) in the State of Piauí, as well as to expand the overall awareness of the distribution of HCV genotyping in Northeast of Brazil. A retrospective cross-sectional study was carried out between April 1999 and August 2005. A total of 153 patients were included, 119 (77.8 percent) males and 34 (22.2 percent) females; mean age = 48.01 ± 9.11 years. We observed a homogeneous distribution between genotypes 1 (50.0 percent) and 3 (49.0 percent), while the most frequent subtype noticed was 3a (49.0 percent). The mean viral load among patients with subtype 1b (1,232,476 UI/mL) was significantly superior to the subtype 1a (391,204 UI/mL; p = 0.010) and to the subtype 3a (594,228 UI/mL; p = 0.047). The average levels of gamma-glutamiltransferase of genotype 1 (144 mg/dL) had statistical differences when compared to genotype 3 (74 mg/dL; p = 0.014). Most patients showed mild to moderate degrees of histopathological necroinflammatory activity and hepatic fibrosis (79.0 percent and 56.2 percent, respectively). We concluded that most candidates to treatment of CHC in the State of Piauí presented with clinically stable hepatic illness; the distribution of genotypes 1 and 3 was virtually homogeneous; and there was no significant demographic or clinical differences among genotypes or subtypes of HCV.

Genotype distributions of the 5 sites SNPs in the 3 subtypes of beta adrenoreceptor / 重庆医科大学学报

Objective:To study the genotype-by site distributions of SNP(single nucleotide polymorphisms)at the 5 sites in the 3 subtypes of beta adrenoreceptor(Beta-AR or B-AR).Methods:DNA was extracted from the peripheral venous blood of 338 subjects using Blood DNA Mini Kit.The 5 sites SNP in the 3 subtypes of Beta-AR were genotyped by PCR-RFLP(polymerase chain reaction-restriction fragment length polymorphism) and allele specified PCR techniques.Results:The natural distribution characteristics for SNP at the 5 sites in the 3 subtypes of Beta-AR of 338 subjects were gotten.The predominant phenotypes are as follows:Beta1-AR wild homozygote Ser/Ser49(70%),Beta1-AR wild homozygote Arg/Arg389(63%),Beta2-AR heterozygote Arg/Gly16(80%),Beta2-AR heterozygote Gln/Glu27(50%),Beta3-AR wild homozygote Trp/Trp64(65%).Conclusion:It is heterogeneous in distribution in different styles for the genotype-by site distribution of SNP at the 5 sites in the 3 subtypes of Beta-AR,which is the basis for further investigating the relationship among the distribution,gene function and diseases.