Background: The glucokinase regulator gene (GCKR) rs780094 has been shown to be strongly associated with some metabolic traits and atherosclerotic parameters, while the association between GCKR rs780094 and carotid intima-media thickness (CIMT) has not been fully investigated in the general population. The associations between the GCKR rs780094 genotype and metabolic traits including CIMT were examined in a Japanese community-dwelling population. Methods: A total of 2491 Japanese adults (907 men and 1584 women) who participated in a medical screening program for the general population from 29 to 94 years of age during 2008 to 2010 were enrolled. GCKR rs780094 was genotyped by the TaqMan polymerase chain reaction method, and associations with metabolic markers including CIMT were evaluated. Results: GCKR rs780094 AA genotype was significantly associated with higher TG (p < 0.001 vs. GG), lower HDL-C (p = 0.021 vs. GG), and lower HbA 1c (p = 0.023 vs. GG). The AA genotype showed significantly thinner CIMT (p = 0.001 vs. GX). These associations were seen only in men. Conclusions: GCKR rs780094 was associated with TG, HDL-C, and HbA 1c levels, as well as with CIMT in Japanese community-dwelling men, but not women.

Recent genome-wide association studies have identified Tribbles homolog 1 (TRIB1) as one of the candidate genes associated with lipid profiles. TRIB1 is known to interact with MAP kinases, thereby regulating their activities. The single nucleotide polymorphism rs2954029 of TRIB1 is located within an intron and is associated with lipid profiles. The aim of the present study is to investigate the TRIB1 rs2954029 (A>T polymorphism) with conventional predictors of coronary artery diseases such as carotid intima-media thickness (CIMT) and cardio-ankle vascular index (CAVI), and with lipid profiles in general population. This study enrolled 2,581 Japanese adults, 942 men and 1,639 women with a median age of 68 years (range 29 to 94 years), who participated in a screening program for the general population living in Goto City, Nagasaki Prefecture, Japan from 2008 to 2010. For the determination of TRIB1 rs2954029 genotypes, the polymerase chain reaction method was used. The differences in each parameter among the TRIB1 rs2954029 genotypes were evaluated using analysis of covariance. Genotype frequencies of TRIB1 rs2954029 in all participants were 25.5% for AA, 50.4% for AT, and 24.0% for TT. In women, the AA genotype showed significantly higher log triglyceride (TG) concentrations than the AT genotype (P = 0.004) and the AT + TT genotypes (P = 0.004). On the other hand, there were no associations with CIMT and CAVI among the TRIB1 rs2954029 genotypes. In conclusion, the TRIB1 rs2954029 is associated with serum TG concentrations in Japanese community-dwelling women.