CD80 and primary biliary cholangitis: The PBC susceptibility locus chromosome 3q13.33 (including ARHGAP31, TMEM39A, POGLUT1, TIMMDC1, and CD80) has been identified by GWAS as a PBC susceptibility locus in European and Chinese populations; consequently, this genome-wide meta-analysis involved replicating chromosome 3q13.33 in the Japanese population.