Distribution of the ACE Gene Polymorphisms in Type 2 Diabetes Mellitus Patients, Their Associations with Nephropathy Biomarkers and Metabolic Indicators at a Tertiary Hospital in Uganda

Purpose: We aimed at determining the distribution of the ACE insertion/deletion gene polymorphisms among type 2 diabetic patients and their association with the nephropathy biomarkers and the metabolic indicators. Patients and Methods: Data were collected from 237 adult type 2 diabetes mellitus patients receiving healthcare at the diabetic clinic of Mbarara Regional Referral Hospital. Peripheral blood genomic DNA was amplified using a conventional PCR technique and analyzed for the ACE homozygous forms of the insertion (II), deletion (DD) and heterozygous insertion deletion (ID) genotypes as well as their respective allele counts. Biomarkers of nephropathy were analyzed on a Beckman coulter AU480 chemistry analyzer using system compatible reagents. Results: Majority of the participants were older persons (Median = 57, IQR = 49– 64) and female 171 (72.2%). Most of them had the Deletion allele 198 (83.5%) and DD genotype 116 (48.9%). At multivariate logistic regression, the nephropathy biomarkers that is microalbuminuria, serum creatinine, urea, eGFR and electrolytes had no association with the ACE I/D alleles or genotypes (p > 0.05). On the other hand, selected metabolic indicators had a positive relationship. The insertion allele was associated with increasing glycated hemoglobin (OR = 1.082, p = 0.019) and decreasing serum glucose levels (OR = 0.891, p = 0.001). Deletion allele was associated with decreasing glycated hemoglobin (OR = 0.924, p = 0.047) and increasing serum glucose levels (OR = 1.208, p = 0.001). ACE II genotype was associated with decreasing serum glucose levels (OR = 0.873, p = 0.029). ACE DD genotype was associated with decreasing glycated hemoglobin (OR = 0.917, p = 0.010) and increasing serum glucose levels (OR = 1.132, p = 0.001). ACE ID genotype was associated with increasing glycated hemoglobin (OR = 1.077, p = 0.022), triglyceride levels (OR = 1.316, p = 0.031) and decreasing serum glucose levels (OR = 0.933, p = 0.038). Conclusion: The presence or absence of the ACE I/D alleles and genotypes affects the ultimate increase or decrease in the serum glucose, glycated hemoglobin and triglyceride levels. Although there was no significant association between the biomarkers of nephropathy and the ACE I/D alleles or genotypes, the above implicated metabolic indicators should be included in healthcare guidelines used when attending to type 2 diabetic patients. Keywords: angiotensin converting enzyme gene, insertion, deletion, polymorphism, biomarkers, type 2 diabetes mellitus, diabetic nephropathy, Uganda