Characteristics of Vitamin D3 Receptor Genotypes in T2DM of Iraqi Obese Women

Objective: This study aims to examine the association between the (rs1544410) polymorphism of the VDR gene with the pathogenesis of T2DM in Iraqi obese women. Methods: A case-control study was performed on 50 patients with T2DM and 50 apparently healthy subjects who were admitted to Al-Hussein Teaching Hospital and Al-Hassan Center of Diabetes and Endocrinology unit / Kerbala health directorate – Iraq during (April 2022 – March 2023). The T2DM groups were divided into two groups, 25 obese and 25 non-obese; the control group was divided into 25 obese and 25 non-obese as apparently healthy groups. The ELISA Kit was used to measure serum 25(OH)D3, heat shock protein-70, VDBP, insulin and C-peptide. Also HbA1c% and insulin resistance (HOMA-IR) were evaluated. The vitamin D3 receptor gene (VDR) variant and the SNP (rs1544410) polymorphism was determined using allele specific polymerase chain reaction, 1.5% agarose gel electrophoresis and then visualized by gel photo-documentation system. Results: The result of vitamin D3 variants genotype (rs 1544410) was a clear band with a molecular size of 200 bps. The size of the amplicon was determined by compare with DNA ladder 100 - 1500 bp. The result of the comparison between observed and anticipated values for SNIP with (rs 1544410) in the tested population was statistically significant, P= < 0.001 and the difference between demographic characteristics and (rs 1544410) SNP, age and BMI shows non-significant difference among all groups. The difference between biomarkers and (rs1544410) SNP was performed using one-way ANOVA test to compare the mean levels of HSP-70, VDBP, C-peptide,  RBC and HbA1c% which shown a non-significant difference among the variants of VDBP Genotype (rs1544410) in  obese women (patients and control) studied groups, p value > 0.05.   Conclusion: The logistic analysis of the (rs1544410) SNP of the patients concluded that HSP-70, VDBP, and C-peptide  level was no significantly related to the also C-peptide, was shown to be a related risk factor to both CT and CT alleles (1.003, p > 0.05) in comparison with CC alleles. Furthermore, HbA1c% level was demonstrated to be related as a risk factor for the CG allele in comparison with CC and GG alleles (1.009, p < 0.05).