Association of Vitamin D Deficiency and Vitamin D Receptor <i>FokI</i> Gene Polymorphism With Diabetic Retinopathy Complications in Ethiopian Patients With Type 2 Diabetes Mellitus

Abstract

Several studies suggest that a deficiency in vitamin D might be a potential risk factor for developing diabetic retinopathy. Research has extensively studied vitamin D receptor genes, such as the FokI gene polymorphisms, and found links between these genetic variations and susceptibility to diabetic retinopathy across different populations. This study aimed to investigate how vitamin D deficiency and vitamin D receptor FokI gene polymorphisms influence the risk of diabetic retinopathy complications in individuals with Type 2 diabetes mellitus. This was a hospital-based case-control research with 153 diabetic retinopathy patients, 153 Type 2 diabetes mellitus patients, and 153 age- and sex-matched healthy controls. Through the collection and analysis of clinical and demographic data, the study assessed the diabetic retinopathy risk factors. The FokI genotypes were determined by analysing DNA isolated from blood samples using polymerase chain reaction and agarose gel electrophoresis. Diabetic retinopathy patients had a much higher prevalence of VDD (OR = 6.24, 95% CI = 3.14-12.39; p < 0.001) than Type 2 diabetes patients and healthy controls. Furthermore, diabetic retinopathy patients had significantly higher frequencies of the FokI ff genotype (OR = 2.04; 95% CI = 1.24-3.75; p = 0.005) and the f allele (OR = 1.56; 95% CI = 1.18-2.06; p = 0.001) than Type 2 diabetes patients and healthy controls. These results indicate that vitamin D deficiency and vitamin D receptor FokI gene polymorphisms are risk factors for the onset and progression of diabetic retinopathy. There is a significant correlation between vitamin D deficiency and the development of diabetic retinopathy. Moreover, the FokI gene of the ff genotype and the f allele have been linked to an increased risk of developing diabetic retinopathy complications in patients with a history of Type 2 diabetes mellitus in the Ethiopian population under study.