The homocysteine associated variant rs548987 of SLC17A3 confers susceptibility to ischemic stroke in Chinese population.

Ischemic stroke is a common cause of death due to obstructed blood supply of the brain. Despite growing numbers of research, etiology underlying ischemic stroke remains complex and elusive. Elevated plasma homocysteine has been known as a risk factor for ischemic stroke. Recently, a genome-wide association study reported association between rs548987 of SLC17A3 and homocysteine. Given existing relation between homocysteine and ischemic stroke, SLC17A3 was believed to be a promising candidate gene of ischemic stroke. Indeed, its association with ischemic stroke was previously reported in a western population. Herein, we used rs548987 as a candidate genetic variant of ischemic stroke and performed association analysis in a Chinese population with 918 ischemic stroke cases and 979 controls. Although rs548987 failed to show significant association with total ischemic stroke and large vessel disease subtype, the C allele of rs548987 showed significant association with small vessel disease subtype of ischemic stroke (OR=0.68, p=0.004). Our preliminary results suggested different genetic etiology underlying the two most common subtypes of ischemic stroke and provided additional evidence to understand contribution of homocysteine to the disease.