PCSK9 and Stroke: The Atherosclerosis Risk in Communities (ARIC) Study of atherosclerosis followed 3,363 black subjects (2.6% had mutations in PCSK9) and 9,524 white subjects (3.2% had mutations in PCSK9) over a 15-year interval and showed no difference in stroke rates between participants with PCSK9 LOF Y142X or C679X variants and controls (Cohen et al., 2006).