Among subjects with a positive diagnosis of FH, 1,015 individuals presented one causative variant in LDLR (N = 1,000) or APOB (N = 15) genes, while in 38 subjects two causative variants were detected (17 LDLR homozygotes, 18 LDLR compound heterozygotes, and three double heterozygotes [LDLR/APOB: N = 2; LDLR/PCSK9: N = 1]) (Supplementary Tables S1–3). This evidence concerns the gene LDLR and familial hyperaldosteronism.