Objective: To investigate the relationship between the susceptibility to cirrhosis and the single nucleotide polymorphisms (SNPs) at C-1350T and G-944C loci of class II transactivator (CIITA) gene promoter IV in chronic HBV carriers.
Methods: C-1350T and G-944C loci of CIITA gene promoter IV were analyzed by sequence-specific primer PCR (PCR-SSP) in 544 chronic HBV carriers and 125 non-HBV infected healthy blood donors.
Results: Among the chronic viral hepatitis B patients, there were significantly decreased frequencies of CC and TG haplotypes, and significantly increased frequency of CG haplotype among patients with liver cirrhosis (CG vs. CC: chi2=8.274, df=1, P < 0.01; CG vs. TG: chi2 = 15.027, df =1, P <0.01). There were no significant differences in the frequencies of CC and TG haplotypes between chronic hepatitis B and liver cirrhosis patients (chi2 = 1.231, df =1, P < 0.05). There were significantly increased frequencies of CC/CC (Group 1) genotype and genotypes contained CG haplotype (Group 3), and significantly decreased frequencies chi2= 7.176, df = 1, P < 0.01; Group1 vs Group 4, chi2 = 19.818, df = 1, P < 0.01; Group 3 vs Group 2, chi2 = 11.423, df = 1, P < 0.01; Group 3 vs Group 4, chi2 = 34.226, df = 1, P < 0.01; Group 1 vs Group 3, chi2 = 0.009, df = 1; Group 2 vs Group 4, chi2 = 2.176, df = 1).
Conclusion: Polymorphisms at -1350 and -944 loci of CIITA gene promoter IV are associated with susceptibility to liver cirrhosis in chronic HBV carriers. The chronic HBV carriers bearing CC/CC genotype or genotypes containing CG haplotype progress into liver cirrhosis with more probability.