Genetic Markers and Proliferative Diabetic Retinopathy

Overview

Type 2 Diabetes (TD2) is the leading cause of new cases of preventable blindness in these countries (and the gold-standard treatment, laser photocoagulation has proven to be effective in preventing vision loss at the end stage of eye disease due to proliferative diabetic retinopathy (PDR) that occurs in 3 to 6 % of the cases.Therefore, the ongoing search for predictive factors of sight threatening stages of diabetic retinopathy has become more important. Previous studies that have examined candidate predictive factors for diabetic eye disease have mostly focused on systemic risk factors leading to PDR. Among various clinical parameters, increased HbA1c % levels, uncontrolled blood pressure, diabetes duration, neuropathy and elevated triglycerides have been associated with PDR. Some genetic factors may also account for the development of PDR and are prospectively considered in this study .

In a previous study (2011), investigators demonstrated a statistically significant relation between the Endothelial Lipase(EL) c.584C\>T polymorphism and the occurrence of diabetic retinopathy in 396 french patients with diabetes type 2 (DT2) with a longitudinal follow-up. Secondly (2014) in a subgroup of 287 DT2 patients, investigators showed the impact of the EL rare T allele was consistent with a recessive mode of inheritance, with homozygotes for the rare allele differing from the carriers of the major allele. Importantly, the homozygotes for the rare T allele were more likely to present with advanced stages of diabetic retinopathy (severe non proliferative and proliferative disease) and particularly with proliferative diabetic retinopathy (PDR). Based on this model investigators decided to conduct a case-control prospective study comparing 155 french patients with DT2 with PDR (cases) and 155 french patients with DT2 without PDR (controls) on the basis of two genetic parameters: EL c.584C\>T polymorphism that investigators previously studied and the C(-106)T aldose reductase polymorphism widely studied in diabetic retinopathy.