Population genetic study of diabetes and diabetic retinopathy among Egyptians

To clarify the population genetic background of diabetes mellitus among Egyptians and its effect on developing diabetic retinopathy (DR).

Genes play an important role in the development of diabetes mellitus.

A statistical study was carried on 214 patients with diabetes mellitus after clinical genetic evaluation including medical and family history, family pedigree analysis, and determination of blood sugar, cholesterol and triglycerides levels. Ophthalmic examination was done to detect diabetic retinopathy.

Family history of diabetes was higher in type I while parental consanguinity was higher in type II. Type I diabetics had positive familial aggregation with sharp falling in frequency of affection from the first to the second to the third degree relatives. Type II diabetes is generally a disease of multifactorial inheritance and AD inheritance in part of pedigrees; however AR inheritance could not be excluded. Family history of DR was higher among diabetic patients with DR than in patients without retinopathy (p < 0.05). Female gender, type I diabetes, duration of diabetes, triglycerides and positive family history of diabetic retinopathy were predictive risk factors for DR.

Genetic factors play an important role in various forms of DM, however the inheritance is complex. Although most cases of DM are multifactorial disorders, monogenic forms have been also identified. Family history is an important risk factor for the development of DR. Molecular studies are recommended to detect which of the implicated genes are responsible for the development of DR among diabetic Egyptians (Tab. 4, Fig. 1, Ref. 18).