[Association study of FADS2 gene rs174575 and rs2845574 single nucleotide polymorphisms with blood pressure and lipid levels in pregnant women].

Objective: To assess the association between the single nucleotide polymorphisms (SNP) rs174575 and rs2845574 of the fatty acid desaturase 2 (FADS2) gene and gestational diabetes mellitus (GDM).

Methods: A total of 1 514 pregnant women who visited West China Second University Hospital of Sichuan University between January 1, 2013 and December 31, 2021 were enrolled in this study. Among them, 583 were diagnosed with gestational diabetes mellitus (GDM group), and 931 had normal pregnancies (control group). The SNPs rs174575 and rs2845574 of the FADS2 gene were analyzed using Sanger DNA sequencing. Plasma levels of insulin (INS), apolipoprotein A1 (apoA1) and apolipoprotein B (apoB) were measured using enzymatic methods, chemiluminescence and immunoturbidimetry. This study was approved by the Medical Ethics Committee of the West China Second University Hospital of Sichuan University (Ethics No.: 2020-036).

Results: The main genotype at the rs174575 C/G and rs2845574 C/T loci were CC in both GDM and control groups. No significant difference was found between the GDM and control groups regarding the genotypic or allelic frequencies of rs174575 and rs2845574 sites (P > 0.05). Among the GDM group, individuals with the GG genotype at the rs174575 site had lower plasma HDL-C levels compared to those with the CC genotype (P < 0.05), and had higher atherogenic indices (AI) compared with the CC and CG genotype (P < 0.05; P < 0.05). Individuals with the TT genotype at the rs2845574 site had higher AI compared with the CT genotype (P < 0.05). Among the control group, individuals with the GG genotype had lower diastolic blood pressure (DBP) compared to those with the CC genotype (P < 0.05). Additional subgroup analysis demonstrated that the rs174575 polymorphism was associated with AI levels in obesity subgroup of GDM, TG levels in non-obese subgroup of control and DBP levels in the obese subgroup of control (P < 0.05; P < 0.05; P < 0.05).

Conclusion: The FADS2 rs174575 and rs2845574 polymorphisms in GDM patients are associated wit HDL-C and AI levels, and the FADS2 rs174575 polymorphisms was also associated with DBP levels in normal pregnant women. The AI and DBP levels have a BMI-dependent effect.