Endogamous marriage and the prevalence of hemoglobin E in ethnic groups of northern Thailand

Objective:To investigate the impact of the endogamous marriage culture on the prevalence of the hemoglobin E(HbE) recessive variant.Methods:The prevalence of the hemoglobin E(HbE)recessive variant was determined by dot-blot hybridization in 4 endogamous villages(1 Mlabri and 3 Htin ethnic groups) in comparison with 9 other nearby non-endogamous populations.Results:Although the overall HbE prevalence in the population studied(8.44%,33/391)was not significantly different from that of the general southeast Asian population,a high prevalence and individuals with homozygous HbE were observed in two villages,the Mlabri from Wiang Sa district and the Htin from Thung Chang district of Nan province(26.3%and26.9%,respectively).The low HbE allelic frequency noticed in some endogamous populations suggests that not only endogamy but also other evolutionary forces,such as founder effect and HbE/β-thalassemia negative selection may have an effect on the distribution of the HbE trait.Conclusion:Our study strongly documents that cultural impact has to be considered in the extensive prevalence studies for genetic disorders in the ethnic groups of northern Thailand.

Taq1B CETP Polymorphism and Cardiovascular Risk in an Endogamous Pop-ulation of Diabetic Men: A Study in Santa Rosa Del Conlara, San Luis, Argentina

Objectives: Type 2 diabetes mellitus (T2DM) patients are at increased risk of cardiovascular diseases (CVDs). Several polymorphisms in the cholesterol ester transfer protein (CETP) gene have been reported. The aim of this study was to determine the distribution and effect of the Taq1B polymorphism in the CETP gene on clinical and biochemical indicators of CVD risk in a population of endogamous-T2DM men. Methods: 102 men (57.5 ± 9.3 years old) inhabitants of Santa Rosa del Conlara, San Luis, Argentina, were recruited and assigned into two groups (22 control and 80 T2DM). Further, these two groups were subdivided according to their Taq1B CETP gene genotypes (i.e., B1B1, B1B2 and B2B2). Clinical and fasting-plasma biochemical indicators of CVD risk were measured and their association with the B1 allele was determined. Results: Compared to control, T2DM men had more central obesity, hypertension, atherogenic index, insulin resistance and poorly controlled diabetes. Compared to T2DM men having the B2 allele, those T2DM men having the B1 allele have increased risk of CVD as assessed by systolic blood pressure (156 ± 16.0 vs 135.8 ± 19.2, p = 0.015), atherogenic index (6.15 ± 1.3 vs 4.4 ± 0.7, p = 0.0008), HDL-c levels (38.9 ± 5.3 vs 64.4 ± 8.2, p ± 3.0 vs 2.4 ± 0.78, p = 0.004). Interestingly, only body mass index (r = ﹣0.559, p = 0.01) and HDL-c concentration (r = ﹣0.492, p = 0.02) negatively correlated with CVD risk in the endogamous population of B1B1 and B1B2 T2DM men. Conclusion: The B1 allele of the CETP gene predicts cardiovascular complications in an endogamous population of T2DM men.