Heritability of quantitative traits associated with type 2 diabetes in an extended family from the United Arab Emirates

The prevalence of Type 2 Diabetes Mellitus (T2DM) in the United Arab Emirates (UAE) is steadily increasing, posing a major public health problem. This study assessed the value of specific clinical markers for T2DM among five generations of an extended Arab family. This family included 319 members of 41 nuclear families; from which 178 individuals (86 males, 92 females; 66 diabetic, 112 healthy) formed the study sample set. The ages of the participants ranged from 4 to 88 years. All participants completed a questionnaire that focused on baseline factors that have previously been associated with T2DM such as diet, smoking, and family history of the disease. The quantitative traits, fasting glucose, glycated hemoglobin (HbA_1c), cholesterol, triglyceride, urea and creatinine levels were measured. Body mass index (BMI) and waist circumference were also recorded. The heritability of these eight quantitative traits were determined with values ranging from 6% to 48%. We found a significant relationship between T2DM diagnosis and waist circumference (p = 2.6, E-9) and BMI (p = 1.0, E-6). The estimated power for these two traits was 80% to 90%, respectively. Creatinine (p = 0.002) and cholesterol (p = 0.02) levels were also associated with T2DM. Our results support the link between environmental and genetic factors in the pathophysiology of T2DM and its related phenotypes in an Arab population.