Association of VDR gene variant rs2228570-FokI with gestational diabetes mellitus susceptibility in Arab women.

Gestational diabetes mellitus (GDM) has been linked with adverse pregnancy outcomes. Vitamin D receptor (VDR) gene variants have been associated with diabetes mellitus susceptibility and related complications. This study assessed the association between VDR gene polymorphism (rs2228570) and GDM risk among pregnant Arab women. A total of 368 pregnant Saudi women who were screened for GDM at 24-28 weeks of gestation and genotyped for the VDR gene variant (rs2228570) were included in this cross-sectional study. Circulatory insulin levels, fasting blood glucose (FBG), glycated hemoglobin (HbA1c), and vitamin D (25(OH)D) were measured. There were 108 women with GDM and 260 women without GDM. The genotype frequency of women with GDM was CC 60.2 %, CT 33.3 %, TT 6.9 %, and CT + TT 39.8 %; for non-GDM women, were CC 61.1 %, CT 31.5 %, TT 6.9 %, and CT + TT 38.4 %. No association was found between the VDR gene variant (rs2228570-FokI) and GDM susceptibility after adjustment for covariates. Serum 25(OH)D had a significant inverse association with FBG (r = -0.49, p = 0.01) and HbA1c (r = -0.45, p = 0.03) among carriers of the TT-genotype. Furthermore, a significant inverse correlation was observed between serum 25(OH)D and HOMA-ß (r = -0.20, p = 0.035) in individuals with the T-allele. Among pregnant Saudi women, glycemic indices appear to be influenced by vitamin D, suggesting a possible role it may play in mitigating the metabolic changes associated with GDM, particularly among individuals with specific genetic backgrounds. In our study population, rs2228570-FokI did not appear to be a significant contributor to GDM risk.

Corrigendum: The association between FokI vitamin D receptor polymorphisms with metabolic syndrome among pregnant Arab women.

[This corrects the article DOI: 10.3389/fendo.2022.844472.].

The Association Between FokI Vitamin D Receptor Polymorphisms With Metabolic Syndrome Among Pregnant Arab Women.

Metabolic syndrome (MetS) is a serious health condition that is becoming extremely threatening in Saudi Arabia. The link between vitamin D receptor (VDR) gene polymorphisms and maternal MetS has been observed in several ethnic groups, but is yet to be clarified in the Arabian population. This study aims to investigate the relationship between the FokI VDR genotype and the risk of MetS and its components in pregnant Saudi women. A cross-sectional study was conducted using 368 pregnant Saudi women on first trimester screened for MetS (44 with MetS and 324 without MetS). Measurements included anthropometrics, glycemic and lipid profile and 25(OH)D. TaqMan genotyping assay was used to determine Fokl VDR genotype of participants. Vitamin D deficiency (25(OH)D <50nmol/l) was seen in 85% of the participants. An estimated 12% of participants had MetS. In the MetS group, the FokI VDR genotyping frequencies for FF, Ff, and ff genotypes were 50%, 36.4% and 13.6%, respectively. In controls, the frequencies were 62.7%, 31.4% and 5.9%, respectively. No significant association between the individual MetS components and FokI VDR genotypes were observed. Nevertheless, carriers of the ff allele had a significant risk for full maternal MetS [Odds Ratio 4.2 (95% Confidence Interval 1.4-12.2; adjusted p=0.009). The study suggests that the ff FokI VDR genotype is a genetic marker of maternal MetS in pregnant Arabian women. Prospective studies that include neonatal outcomes may confirm present findings.

Vitamin D and gestational diabetes mellitus.

The incidence of gestational diabetes mellitus (GDM) is increasing worldwide. GDM can be responsible for an important proportion of adverse fetal and maternal outcomes during pregnancy, and it is associated with long-term health deterioration for both mother and child. Therefore, it is important to identify potentially modifiable risk factors for GDM. Accumulating evidence links vitamin D deficiency with abnormal glucose metabolism, and epidemiological studies have shown that women who develop GDM are more likely to be vitamin D deficient. This review discusses the prevalence, risk factors, and outcomes of GDM and vitamin D deficiency in pregnant women, outlines the possible mechanism of action of vitamin D in glucose homeostasis, and summarizes emerging evidence that associates vitamin D deficiency with the risk of developing GDM. This critical review of the literature indicates there is a need for intervention trials to test the possible beneficial effect of vitamin D supplementation in pregnant women with low vitamin D status to reduce the risk of developing GDM.