Cytotoxic T lymphocyte-associated antigen-4 gene polymorphisms and biliary atresia susceptibility in Chinese children.

Biliary atresia (BA) is a devastating liver disease of complex pathogenesis in neonates, characterized by an inflammatory and fibrosing obstruction of extrahepatic bile ducts. Cytotoxic T lymphocyte-associated antigen-4 (CTLA4) is expressed on the surface of a subset of regulatory T cells (Treg) and down regulates the human immune response. To investigate the possible association between CTLA4 gene polymorphisms and BA susceptibility, we conducted a case-control study in the Chinese children. Three single nucleotide polymorphisms (SNPs) in the CLTA4 gene (rs231725, rs231775 and rs3087243) were genotyped in 113 BA patients and 133 healthy controls. The statistical analysis revealed no significant difference between BA patients and healthy controls in allele or genotype frequencies (rs231725, P = 0.2718, OR = 0.814, 95% CI = 0.564-1.175; rs231775, P = 0.1599, OR = 1.316, 95% CI = 0.897-1.931; rs3087243, P = 0.0572, OR = 1.582, 95% CI = 0.984-2.543), neither in the distribution of haplotypes of these CTLA4 gene SNPs. The result of our study is the first one to provide the evidence that there is no significant association between CLTA4 gene polymorphisms and BA susceptibility in Chinese children.