The insertion/deletion polymorphism of angiotensin-converting enzyme gene predisposes Cameroon female type 2 diabetes mellitus patients to essential hypertension

Abstract

The association between type 2 diabetes mellitus (T2DM) and essential hypertension (EH) is not well  understood. Both conditions result from an interaction of multiple genetic (ethnic) and environmental (geographical) factors. One possible genetic determinant is the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism. Observations on the association between this polymorphism and EH in T2DM patients have been inconsistent in different populations. Given the high prevalence of EH in diabetic patients in the South West Region (SWR) of Cameroon, the aim of this work was to study the relationship between I/D polymorphism of the ACE gene and hypertension in T2DM patients. ACE I/D polymorphism was determined by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and D/D typing was further reconfirmed using insertion-allele-specific amplification. Analysis of ACE genotype and allele frequencies revealed statistically insignificant differences between the normotensive and hypertensive T2DM subjects. On the contrary, the frequency of the I allele was significantly lower in the normotensive than the hypertensive diabetic females. These findings suggest that the I allele of the ACE gene predisposes female T2DM patients to EH.

Key words: Diabetes, Hypertension, Angiotensin converting enzyme, Insertion deletion, Genetic polymorphism