Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases
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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. · 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.