PCSK9 and familial hyperaldosteronism: Amongst the 257 adult patients (defined as ≥18 years at date of genetic screening) included in the study, 34% or 87/257 had genetically confirmed heterozygous FH (corresponding to “definite FH” using the Simon Broome criteria); of which 94% had the LDLR mutation (82/87), 5% (4/87) had the ABOB mutation and only 1% (1/87) had the PCSK9 mutation; consistent with the mutation distribution observed in earlier studies.13,14 The genetically unconfirmed group (n=170) corresponded to “possible FH” using the Simon Broome criteria).