Other SNPs in core circadian genes, such as BMAL1, that forms a complex with CLOCK, have been associated with T2D prevalence in some human studies and in murine models [11, 32, 54, 55] reinforcing the contribution of the circadian system to the etiology of T2D; however, no human study has reported an association between SNPs in core circadian genes and incidence of stroke as demonstrated in the current study. Here, CLOCK is linked to type 2 diabetes mellitus.