Since UGT1A1 is considered to be the only enzyme with substantial glucuronidation activity on bilirubin18, we further explored the possibility that the association is driven by a regulatory effect on UGT1A1. We performed colocalization analysis between neonatal jaundice and cis-eQTLs in 127 tissues/cell types from the eQTL Catalog19, and observed colocalization with UGT1A1 expression in the colon, but not in the liver (Fig. 1, Supplementary Fig. 6 and Supplementary Data 5). The gene discussed is UGT1A1; the disease is neonatal jaundice.