Biliary atresia causes jaundice and liver failure in newborn children. In this study, single nucleotide polymorphisms were characterized in children with biliary atresia and identified ARF6 as a susceptibility gene for this disease. Knockdown of this gene in zebrafish embryos impaired formation of bile ducts and excretion of bile from the zebrafish liver. Subject enrollment: Children with biliary atresia were enrolled at Children's Hospital of Pittsburgh (CHP) after obtaining written consent from parents for the University of Pittsburgh IRB approved protocol number 0405628. At the Center for Applied Genomics (CAG), all subjects were enrolled after obtaining written consent from parents per Children's Hospital of Philadelphia IRB approval number 06-004886 Genotyping array: Genotyping of DNA obtained from blood was performed with the Infinium HumanHap550K BeadChip (Illumina, San Diego, CA). Statistical methods and software: SNP genotype frequencies were compared between cases and controls with a chi-square test statistic applied in Plink [Purcell et al, 2007] for SNPs with at least 90% call rate and 1% minor allele frequency (MAF). Cases and controls: All DNA samples had excellent data quality with call rates > 98%. A total of 63 Caucasian BA cases and 1907 controls were compared at > 550000 SNPs, and demonstrated a very low genomic inflation factor of 1.00627. Description of Cases: Biliary atresia patients had received a Kasai procedure and demonstrated histopathological features of biliary obstruction, and were recruited at evaluation for transplantation or after liver transplantation.

Genome-Wide Association Study of Biliary Atresia

PLINK: a tool set for whole-genome association and population-based linkage analyses.

The Role of ARF6 in Biliary Atresia