PCSK9 and homozygous familial hypercholesterolemia: Of the 3494 subjects, 2714 had genetically confirmed HeFH: 90.7% in LDLR gene, 9.0% in APOB gene and 0.3% in PCSK9 gene; 41 patients had genetically confirmed HoFH; 583 were non-affected siblings (genetically confirmed non-FH); and 156 had a clinical diagnosis of HeFH but without a known pathogenic variant yet found.