Common genetic variants of GPC1 gene reduce risk of biliary atresia in a Chinese population

Background: Biliary atresia (BA) is a major neonatal cholestatic disease and main indication for pediatric liver transplantation in the world. Recently, GPC1 has been implicated as a risk gene for BA by genetic studies and follow-up functional experiments on zebrafish.

Methods: Two common genetic variants of GPC1, rs2292832 and rs3828336, were selected systematically through 'SNPinfo', and were examined using TaqMan Genotyping Assays for association studies in a Chinese population containing 134 cases and 618 controls.

Results: Of the two single nucleotide polymorphisms (SNPs), we found a significantly decreased BA risk associated with rs2292832 (additive model: OR=0.638, 95% CI: 0.467-0.873, P=0.005), and a marginal effect for rs3828336 (heterozygous model: OR=0.564, 95% CI: 0.312-1.020, P=0.058). The haplotype analysis indicated that either Crs2292832-Crs3828336&Trs3828336 or Trs2292832-Trs3828336 conferred a protective effect from BA (OR=0.569, 95% CI=0.414-0.783, P<0.001; OR=0.528, 95% CI: 0.301-0.926, P=0.026). Moreover, bioinformatics analysis suggested that rs2292832 altered GPC1 expression via effect on transcription-factor-binding sites (TFBS) of upstream binding transcription factor (UBTF), as a regulatory DNA variation in Deoxyribonuclease I (DNase I) hypersensitive sites (DHSs).

Conclusion: Common variants of GPC1 gene were genetically involved in BA risk.