UNC45A and cholestasis: The osteo-oto-hepato-enteric (O2HE) syndrome (OMIM #619377), which combines congenital secretory diarrhea, cholestasis, hearing impairment, and bone fragility, has recently been linked to loss-of-function mutations in the Unc-45 myosin chaperone A (UNC45A) gene, encoding a myosin cochaperone (1).