PCSK9 and familial hyperaldosteronism: The most common cause of FH is a mutation in one of the following three genes: low-density lipoprotein receptor (LDLR, MIM #606945), which accounts for nearly 90% of causal mutations; apolipoprotein B (APOB; MIM# 107730), and proprotein convertase subtilisin/kexin type 9 (PCSK9; MIM# 607786)2.