Sex-specific association of FABP2 polymorphisms with the risk of obesity in the Tehran Cardio-Metabolic Genetic Study (TCGS).

FABP2 is one of the key genes involved in obesity development across different populations. However, there is no comprehensive report about the FABP2 contribution to obesity incidence among Iranians. Hence, the present study was designed to assess the probable role of FABP2 polymorphisms in obesity incidence in the Tehran Cardio- metabolic Genetic Study (TCGS) representative Iran population. Unrelated adults who had BMI information for at least 3 consecutive phases of the TCGS cohort were included. The control and case groups were defined as individuals who always had long-term persistent normal weight (20 < BMI < 25; n = 1526) and individuals who were long-term persistent obese (30 < BMI < 35; n = 1313), respectively. The logistic regression test was used to assess the possible association between SNPs located in and around the FABP2 gene with obesity. Also, we used Haploview and SHEsis to perform haplotype analysis to detect whether or not this chromosomal region is correlated with obesity. We found a gender-dependent association between the rs10857064 FABP2 and the risk of obesity. The presence of the rs10857064-G allele could significantly increase the risk of obesity only in women, not men (OR = 1.26; 95 % CI: 1.02-1.57; p = 0.03). Through haplotype analysis, we also detected that the TG haplotype containing rs7670862 and rs10857064 could significantly enhance the risk of obesity in women, further supporting the central role of rs10857064 in women's long-term obesity risk. In the current study, we revealed that rs10857064-G FABP2 can significantly predispose women to develop obesity. It highlights the importance of different genetic variants in both genders, which could help us to distinguish more efficient obesity screening tests and treatments based on gender in the future.

Kernel machine SNP set analysis finds the association of BUD13, ZPR1, and APOA5 variants with metabolic syndrome in Tehran Cardio-metabolic Genetics Study.

Metabolic syndrome (MetS) is one of the most important risk factors for cardiovascular disease. The 11p23.3 chromosomal region plays a potential role in the pathogenesis of MetS. The present study aimed to assess the association between 18 single nucleotide polymorphisms (SNPs) located at the BUD13, ZPR1, and APOA5 genes with MetS in the Tehran Cardio-metabolic Genetics Study (TCGS). In 5421 MetS affected and non-affected participants, we analyzed the data using two models. The first model (MetS model) examined SNPs' association with MetS. The second model (HTg-MetS Model) examined the association of SNPs with MetS affection participants who had a high plasma triglyceride (TG). The four-gamete rules were used to make SNP sets from correlated nearby SNPs. The kernel machine regression models and single SNP regression evaluated the association between SNP sets and MetS. The kernel machine results showed two sets over three sets of correlated SNPs have a significant joint effect on both models (p < 0.0001). Also, single SNP regression results showed that the odds ratios (ORs) for both models are almost similar; however, the p-values had slightly higher significance levels in the HTg-MetS model. The strongest ORs in the HTg-MetS model belonged to the G allele in rs2266788 (MetS: OR = 1.3, p = 3.6 × 10-7; HTg-MetS: OR = 1.4, p = 2.3 × 10-11) and the T allele in rs651821 (MetS: OR = 1.3, p = 2.8 × 10-7; HTg-MetS: OR = 1.4, p = 3.6 × 10-11). In the present study, the kernel machine regression models could help assess the association between the BUD13, ZPR1, and APOA5 gene variants (11p23.3 region) with lipid-related traits in MetS and MetS affected with high TG.