PCSK9 and coronary artery disorder: Autosomal dominant familial hypercholesterolaemia (FH) is caused by a heterozygous DNA variant in either LDLR, APOB, PCSK9 or APOE genes, leading to defective clearance of low-density lipoprotein cholesterol (LDL-C).1, 5 Affected individuals have an increased risk of coronary heart disease (CHD) at all ages: standardised incidence ratios for CHD in men and women are 11.1 and 17.3 at ages 25–39, 6.7 and 8.7 at 40–49, 3.3 and 4.5 at 50–59, and 3.3 and 3.1 at 60–69.6