Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases
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Infect. Genet. Evol. · Apr 2015
Toll-like receptor 1 and 10 polymorphisms, Helicobacter pylori susceptibility and risk of gastric lesions in a high-risk Chinese population.
Genetic polymorphisms of Toll-like receptor (TLR) 1 and 10 may influence Helicobacter pylori (H. pylori) susceptibility. To evaluate associations between TLR1 and 10 polymorphisms, H. pylori infection, and precancerous gastric lesions, a population-based study was conducted in a high-risk Chinese population. Three single-nucleotide polymorphisms, TLR1 rs4833095, TLR10 rs10004195, and TLR10 rs4129009 were genotyped by TaqMan SNP genotyping assay in 2553 participants with diverse gastric lesions. ⋯ The risk of CAG was also decreased in subjects carrying TLR10 rs10004195 T allele (OR=0.75; 95%CI: 0.57-0.99). Furthermore, haplotype analysis indicated that haplotype TT of rs4833095 and rs10004195 had a protective effect on H. pylori infection (OR=0.83; 95%CI: 0.72-0.96) or precancerous gastric lesions (OR=0.78; 95%CI: 0.64-0.96 for CAG, and OR=0.74; 95%CI: 0.57-0.96 for IM). These findings suggest that TLR1 rs4833095 and TLR10 rs10004195 may play crucial roles in H. pylori susceptibility and gastric pathogenesis.
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Infect. Genet. Evol. · Mar 2015
Identification of the source of A (H10N8) virus causing human infection.
A novel H10N8 influenza A virus has been detected in three humans in China since December 2013. Although this virus was hypothesized to be a novel reassortant among influenza viruses from wild birds and domestic poultry, its evolutionary path leading to human infection is unknown. Sporadic surveillance at the live poultry market (LPM) suspected to be the source of infection for the first H10N8 patient has shown a gradual increase in influenza virus prevalence culminating with a predominance of H10N8 viruses. ⋯ These H10N8 viruses have continued to evolve within this LPM subsequent to the human infection, and continuous assessments of these H10N8 viruses will be necessary. Serological surveillance showed that the virus appears to have been present throughout the LPM system in Nanchang, China. Reduction of the influenza virus burden in LPMs is essential in preventing future emergence of novel influenza viruses with zoonotic and pandemic potential.
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Infect. Genet. Evol. · Dec 2014
Impacts of human leukocyte antigen DQ genetic polymorphisms and their interactions with hepatitis B virus mutations on the risks of viral persistence, liver cirrhosis, and hepatocellular carcinoma.
Human leukocyte antigen (HLA)-DQ genetic polymorphisms have been associated with chronic hepatitis B virus (HBV) outcomes. We aimed to determine impacts of HLA-DQ polymorphisms and their interactions with HBV mutations on the risks of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). rs2856718 (A>G) and rs9275319 (A>G) were genotyped in 1342 healthy controls, 327 HBV surface antigen (HBsAg) seroclearance subjects, 611 asymptomatic HBsAg carriers (ASCs), 1144 chronic hepatitis B (CHB) patients, 734 LC patients, and 1531 HCC patients using quantitative PCR. HBV mutations were detected by direct sequencing. ⋯ A rs9275319 variant genotype (GG) was significantly associated with an increased frequency of preS1 start codon mutation, an HCC-risk mutation, in genotype C. The interaction of rs2856718 AG+GG genotype with T1753V, a HCC-risk mutation, significantly reduced LC risk, with an OR of 0.26 (95% CI, 0.09-0.78); whereas the interaction of rs2856718 AG genotype with C1673T, a LC-risk mutation, significantly increased HCC risk, with an OR of 2.80 (95% CI, 1.02-7.66) in genotype C HBV-infected subjects. Conclusively, the HLA-DQ polymorphisms affect the risks of LC and HCC differently in chronic HBV-infected subjects, possibly via interacting with the HBV mutations.
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Infect. Genet. Evol. · Dec 2014
Molecular epidemiology of human G2P[4] rotaviruses in Taiwan, 2004-2011.
In 2006, two rotavirus vaccines (Rotarix and RotaTeq) became available on the private market in Taiwan. Although vaccine coverage is currently low, molecular surveillance of rotavirus strains can provide pertinent information for evaluation of the potential impact of vaccine introduction and infection control. During January 2008-December 2011, children aged <5 years hospitalized with acute gastroenteritis were enrolled from sentinel surveillance hospitals in three geographic areas of Taiwan. ⋯ Lineage V within both G2 and P[4] represented newly recognized genetic variants of the respective genotypes. The distribution of individual combinations of the G2 and P[4] (sub)lineages showed some temporal variations. This study provides further evidence for the great genetic diversity among G2P[4] strains and helps understand the epidemiological trends of these strains among children in Taiwan.
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Infect. Genet. Evol. · Oct 2014
Association of IL-2 polymorphisms and IL-2 serum levels with susceptibility to HBV-related hepatocellular carcinoma in a Chinese Zhuang population.
Interleukin-2 (IL-2) is an immunoregulatory cytokine produced by T cells and plays an important role in antitumor immunity. Variations in the DNA sequence of the IL-2 gene may lead to altered cytokine production and/or activity, and thus modulate an individual's susceptibility to hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC). To test this hypothesis, we investigated whether IL-2 gene polymorphisms and its serum levels are associated with HBV-related HCC in a Chinese population. ⋯ The results suggested that the IL-2 +114T/G polymorphism may contribute to increased HBV-related HCC risk through regulating the serum IL-2 levels. Further large and well-designed studies in diverse ethnic populations are needed to confirm our results.