CDKN2A and atherosclerosis: The linkage disequilibrium block that contains SNP rs4977574 harbors a gene that encodes a large antisense noncoding RNA (ANRIL), which is expressed in endothelial cells.37,38 Expression of ANRIL is associated with atherosclerosis and may be involved in the regulation of the cyclin-dependent kinase inhibitor 2A and 2B genes.39,40 The MTAP gene, which encodes methylthioadenosine phosphorylase, an essential enzyme in polyamine metabolism, has also been found to be associated with atherosclerosis.