Association of Auto-Antigen SLC30A8 Gene Variants with Type 1 Diabetes Mellitus

Abstract

Type 1 Diabetes Mellitus (T1DM), is a genetic disease, the prevalence of which is increasing due to delays in the diagnosis because of the absence of standard antibodies. Therefore, there is a need for a molecular variant that can help in early diagnosis in these patients. The polymorphism in the SLC30A8 gene can identify the people at risk of T1DM. However, there is a controversy in the association of the SLC30A8 gene in the pathogenesis of T1DM and a dearth of data in our part of the world. Therefore, we aimed to determine the most frequent autoantigen SLC30A8 genotype and its association with T1DM in the Pakistani population. This case-control study was carried out at Ziauddin Medical University (ZMU) jointly with Baqai Institute of Diabetology and Endocrinology (Baqai Medical University) from June to October 2019. A total of 50 subjects were enrolled (25 cases and 25 controls) in the study. Cases included 25 diagnosed patients of T1DM meeting American Diabetes Association (ADA) new criteria and controls were their first-degree relatives. Blood was drawn, DNA was extracted and amplified through PCR. The RFLP of PCR product was done using a restriction enzyme, Alu I for genotyping. The most frequently observed genotype was CC among cases as well as controls. The CC genotype of rs13266634 was not found significantly associated with T1DM (p=0.08) but the OR was 2.7; CI=0.86 -9.00. Similarly other genotypes were also not found statistically significant. However, HbA1C and Fasting Blood Sugar (FBS) were found statistically significant (p=0.001, p=0.000) in T1DM patients compared to controls. The autoantigenic variants of SLC30A8 of rs13266634 were not found statistically significant with T1DM. The role of this variant as a susceptibility gene in T1DM development should be further confirmed by carrying out studies with a larger sample size.