Abstract
Background: The interaction between obesity and genetic traits on high density lipoprotein (HDL) levels has been extensively studied. The variance of serum HDL has a strong genetic heritability, although the studied variant only explains a small part of this variation. The goal of this study was to investigate the associations between the apolipoprotein type 2 (APOA2) rs3813627 single nucleotide polymorphism (SNP) and anthropometric and biochemical variables, though body mass index (BMI). Methods: This study included 153 subjects (91 overweight/obese (BMI³25 kg/m(2)) and 62 non-obese individuals (BMI < 25 kg/m(2))). The APOA2 rs3813627 SNP was selected and genotyped. Genotype analysis was performed to analyze the associations between APOA2 SNPs and anthropometric and biochemical variables through BMI. Results: The APOA2 rs3813627 TT genotype was associated with low HDL levels in comparison with the APOA2 rs3813627 GG and GT genotype in overweight/obese individuals, but not in the non-obese subjects (p < 0.05). The same trend was observed in the apolipoprotein type 1 (APOA1) protein levels (p < 0.05). Correlation analysis revealed a negative correlation between HDL and APOA1 levels and APOA2 rs3813627 SNP under recessive model (p < 0.05). The odds ratio for low HDL levels was 3.76 and 3.94 for low APOA1 levels. The mediation analysis of APOA2 rs3813627 SNP through BMI showed a full mediation on HDL and partial mediation on APOA1 levels (p < 0.05). Bioinformatic analysis showed that rs3813627 lies in the APOA2 promoter and overlaps motifs for several bound transcription factors. Conclusion: On the basis of these data, the APOA2 rs3813627 SNP is associated with low HDL and APOA1 levels susceptibility, and this effect was mediated by an increased BMI.