The role of K121Q ENPP1 polymorphism in diabetes mellitus and its complications

• Published in: Brazilian journal of medical and biological research Vol. 41; no. 3; pp. 229 - 234
• Main Authors: Leitão, C B, Nabinger, G B, Krahe, A L, Bolson, P B, Gerchman, F, Friedman, R, Gross, J L, Canani, L H
• Format: Journal Article
• Language: English
• Published: Brazil Associação Brasileira de Divulgação Científica 01.03.2008
• Subjects: African Continental Ancestry Group - genetics; BIOLOGY; Case-Control Studies; Cross-Sectional Studies; Diabetes Complications - ethnology; Diabetes Complications - genetics; Diabetes Mellitus, Type 2 - ethnology; Diabetes Mellitus, Type 2 - genetics; ENPP1 polymorphism; Ethnicity; European Continental Ancestry Group - genetics; Female; Gene Frequency - genetics; Genetic Predisposition to Disease - ethnology; Genetic Predisposition to Disease - genetics; Genotype; Humans; Male; MEDICINE, RESEARCH & EXPERIMENTAL; Middle Aged; Phosphoric Diester Hydrolases - genetics; Polymerase Chain Reaction; Polymorphism, Genetic - genetics; Pyrophosphatases - genetics; Type 2 diabetes mellitus; ENPP1 polymorphism; Ethnicity; Type 2 diabetes mellitus
• ISSN: 0100-879X; 1414-431X; 1414-431X
• DOI: 10.1590/s0100-879x2006005000202

The aim of the present study was to analyze the frequency of K121Q polymorphism in the ENPP1 gene of Brazilian subjects according to ethnic origin and to determine its possible association with diabetes mellitus (DM) and/or diabetic complications. A cross-sectional study was conducted on 1027 type 2 DM patients and 240 anonymous blood donors (BD). Ethnicity was classified based on self-report of European and African descent. The Q allele frequency was increased in African descendant type 2 DM patients (KK = 25.9%, KQ = 48.2%, and QQ = 25.9%) and BD (KK = 22.0%, KQ = 53.8%, and QQ = 24.2%) compared to European descendant type 2 DM patients (KK = 62.7%, KQ = 33.3%, and QQ = 4.1%) and BD (KK = 61.0%, KQ = 35.6%, and QQ = 3.4%). However, there was no difference in genotype distribution or Q allele frequency between diabetic and non-diabetic subjects (European descendants: DM = 0.21 vs BD = 0.21, P = 0.966, and African descendants: DM = 0.50 vs BD = 0.51, P = 0.899). In addition, there were no differences in clinical, laboratory or insulin resistance indices among the three genotypes. The prevalence of DM complications was also similar. In conclusion, K121Q polymorphism is more common among Afro-Brazilian descendants regardless of glycemic status or insulin sensitivity indices. Likewise, insulin sensitivity and DM chronic complications appear not to be related to the polymorphism in this sample.