The PCSK9 genetic risk score was associated with a 40% lower risk of CHD (OR: 0.60, 95% CI: 0.49–0.74, P = 1 × 10−6) but a non-significant effect on IS (OR: 1.07, 95% CI: 0.71–1.60, P = 0.76) per 1 mmol/L lower LDL-C, suggesting significant heterogeneity between the effects of PCSK9 on CHD and on IS risk (P for heterogeneity = 0.01). Here, PCSK9 is linked to coronary artery disorder.