To the Editor: In their study of loss-of-function mutations in the ABCA1 gene, Dr Frikke-Schmidt and colleagues1 reported that heterozygosity for certain ABCA1 variants was not associated with increased risk of ischemic heart disease (IHD) in 3 Danish cohorts and concluded that reduced high-density lipoprotein (HDL) cholesterol levels caused by mutations in ABCA1 do not contribute to atherosclerosis. However, a number of limitations preclude this conclusion.
Brunham LR, Kastelein JJP, Hayden MR. ABCA1 Gene Mutations, HDL Cholesterol Levels, and Risk of Ischemic Heart Disease. JAMA. 2008;300(17):1997-1998. doi:10.1001/jama.2008.539