Genetic loci for retinal arteriolar microcirculation.
PLoS ONE 2013 ; 8: e65804.
Sim X, Jensen RA, Ikram MK, Cotch MF, Li X, MacGregor S, Xie J, Smith AV, Boerwinkle E, Mitchell P, Klein R, Klein BE, Glazer NL, Lumley T, McKnight B, Psaty BM, de Jong PT, Hofman A, Rivadeneira F, Uitterlinden AG, van Duijn CM, Aspelund T, Eiriksdottir G, Harris TB, Jonasson F, Launer LJ, Wellcome Trust Case Control Consortium 2, Attia J, Baird PN, Harrap S, Holliday EG, Inouye M, Rochtchina E, Scott RJ, Viswanathan A, Global BPGen Consortium, Li G, Smith NL, Wiggins KL, Kuo JZ, Taylor KD, Hewitt AW, Martin NG, Montgomery GW, Sun C, Young TL, Mackey DA, van Zuydam NR, Doney AS, Palmer CN, Morris AD, Rotter JI, Tai ES, Gudnason V, Vingerling JR, Siscovick DS, Wang JJ, and Wong TY
PubMed ID : 23776548
PMCID : PMC3680438
Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene) was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8). This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12) in combined meta-analysis of discovery and replication cohorts). In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.