Evidence for distinct genetic effects on obesity and lipid-related CVD risk factors in diabetic compared to nondiabetic American Indians: the Strong Heart Family Study

Background The relationship between diabetes and increased cardiovascular disease (CVD) risk is well established. Previous data from the Strong Heart Family Study (SHFS) have demonstrated significant heritabilities for CVD risk factors and implicated diabetes as an important predictor of several of the phenotypes in three large groups of American Indians in Arizona (AZ), Oklahoma (OK), and the Dakotas (DK). However, the genetic architecture of this relationship is not well understood. The purpose of the present paper is to determine whether the genetic effects on C-VD risk factors in the SHFS are different in diabetic and nondiabetic individuals. Methods Approximately 950 men and women, 18 years or older, in 32 extended families, were examined between 1997 and 1999. Interaction between genotype and diabetes status was estimated for nine CVD risk factors [body fat mass (FAT), body mass index (BMI), high-density lipoprotein cholesterol (HDL-C), log-transformed fibrinogen, log-transformed triglycerides, log-transformed urinary albumin: creatinine ratio (LACR), plasminogen activator inhibitor 1 (PAI-1), systolic blood pressure (SBP), and waist-to-hip ratio (WHR)], using a maximum likelihood variance decomposition technique. Results We found evidence that genetic factors influencing BMI, FAT, log-transformed triglycerides, HDL-C, and WHR are differentially expressed in individuals with diabetes compared to those without diabetes. Conclusion Thus, may be distinct genetic determinants of various CVD risk factors. Copyright (C) 2002 John Wiley Sons, Ltd.