KCNJ8 and hypertrichotic osteochondrodysplasia Cantu type: Gain‐of‐function mutations in KCNJ8 and ABCC9 cause the rare heritable disorder Cantu Syndrome, while loss‐of‐function (LoF) mutation of ABCC9 was recently identified as the cause of a novel syndrome, ABCC9‐related intellectual disability and myopathy syndrome (AIMS; Harakalova et al, 2012; Brownstein et al, 2013; Smeland et al, 2019).