RNF213 and polycystic kidney disease: Extra‐cerebral manifestations associated with RNF213 variants have also been described clinically, including an infant who presented with elevated aminotransferases found on biopsy to have lysosomal neutral fat accumulation and cytoplasmic cholesterol crystals in addition to MMD (Harel et al., 2015), a child who presented with a dysplastic right kidney in addition to MMD (Dibi, Maana, Jabourik, & Bentahila, 2017), and a young adult with polycystic kidneys as well as MMD (Pracyk & Massey, 1989).