title: Genetic variation at -1878 (rs2596542) in MICA gene region is associated with chronic hepatitis B virus infection in Saudi Arabian patients.
abstract: MHC class I polypeptide-related chain A (MICA), mapping to 6p21.33, belongs to the non-classical class I family and its expression is induced by several stress factors including viral infection. A recent genome-wide association study has identified a single nucleotide polymorphism (SNP) of MICA, rs2596542 to be significantly associated with hepatitis C-induced hepatocellular carcinoma (HCC) in a Japanese population. Therefore, this study aims to investigate whether the SNP rs2596542 plays any role in hepatitis B virus (HBV) sero-clearance or in the development of complications associated with chronic HBV such as cirrhosis and/or HCC. TaqMan genotyping assay was used to identify the association of the SNP among 584 normal healthy controls and 777 HBV-infected patients. The patient group was further categorized into inactive carriers (Group I), active carriers (Group II), cirrhosis (Group III) and cirrhosis-HCC (Group IV). Variation at this SNP was found to be significantly more frequent in control subjects than in patients (OR = 0.852; 95% C.I. = 0.730-0.994; p = 0.0415). Also, the SNP was found to have a highly significant association when the inactive carriers were compared to the rest of the patients (OR = 1.308; 95% C.I. = 1.058-1.617; p = 0.0130). The TT genotype was found to occur more frequently among active HBV carriers (groups II, III and IV) when compared to inactive HBV carriers, thus suggesting that the rs2596542-T may be recessively associated with an active HBV infection. However, no significant association was observed in the case of HBV-related cirrhosis or HCC. These findings indicate that the MICA rs2596542 has a significant role in HBV infection.
authors.affiliation: Department of Infection and Immunity, Research Center, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia; Liver Disease Research Center, King Saud University, Riyadh, Saudi Arabia. Electronic address: aqahtani@kfshrc.edu.sa.
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Al-Qahtani
authors.forename: Mashael
authors.initials: M
authors.lastname: Al-Anazi
authors.forename: Ayman A
authors.initials: AA
authors.lastname: Abdo
authors.forename: Faisal M
authors.initials: FM
authors.lastname: Sanai
authors.forename: Waleed
authors.initials: W
authors.lastname: Al-Hamoudi
authors.forename: Khalid A
authors.initials: KA
authors.lastname: Alswat
authors.forename: Hamad I
authors.initials: HI
authors.lastname: Al-Ashgar
authors.forename: Nisreen
authors.initials: N
authors.lastname: Khalaf
authors.forename: Nisha
authors.initials: N
authors.lastname: Viswan
authors.forename: Mohammed N
authors.initials: MN
authors.lastname: Al-Ahdal
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000209:etiology* / Q000473:pathology; D016022:Case-Control Studies; D004279:DNA, Viral / Q000235:genetics; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000150:complications / Q000235:genetics* / Q000821:virology; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D006801:Humans; D008103:Liver Cirrhosis / Q000150:complications / Q000235:genetics* / Q000821:virology; D008113:Liver Neoplasms / Q000209:etiology* / Q000473:pathology; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011379:Prognosis; D012529:Saudi Arabia
chemical_list: D004279:DNA, Viral; D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A
keywords: HBV; HCC; MICA; Saudi Arabia; Single nucleotide polymorphism