KLB and cartilage-hair hypoplasia: While the association of KLB variants with colonic transit and liver damage fits well with the known function of KLB as a critical regulator of bile acid homeostasis, other KLB variants were linked with phenotypes less clearly connected to bile acid metabolism, including alcohol intake, congenital hypogonadotrophic hypogonadism (CHH), and insulin-mediated pseudoacromegaly (IMPA) (22, 23, 26).