Common Variants Associated with Type 2 Diabetes in a Black South African Population of Setswana Descent: African Populations Diverge

Abstract

The increasing worldwide prevalence of type 2 diabetes mellitus (T2D) is a serious global health concern. Although T2D has a strong genetic etiology, limited knowledge exists about the common variants associated with it in the black South African population. This study set out to evaluate the association of previously reported common variants in other world populations with T2D susceptibility in a black South African population of Setswana descent. A case-control study design of 178 cases and 178 controls nested in the Prospective Urban Rural Epidemiology (PURE) study was conducted wherein we genotyped for 77 single nucleotide polymorphisms (SNPs). PLINK software was used to evaluate the standard genetic models of disease penetrance for the association of the common variants with impaired glucose tolerance (IGT) while adjusting for age, sex, and body mass index. Only rs1436955 significantly associated with an increase in T2D risk; three other variants, rs831571, rs8050136, and rs7542900, significantly associated with decreased risk of T2D. However, none of the four SNPs had significant associations after correcting for multiple testing (p<0.05). Although further studies are required to confirm these observations, the common variants associated with T2D risk among the Black South Africans of Setswana descent might likely be different than those in the Asian and European populations. This study supports the broader thesis that the genetic background of Africans is diverse and cannot be directly extrapolated using genetic variants from other ethnicities. Therefore there is a need to identify the population-specific variants linked with T2D in Africa.

Heritability and Genetics of Type 2 Diabetes Mellitus in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

“…In single studies, the ABCC8 and Haptoglobin SNPs were found to be associated with T2DM among Nigerians [ 51 ] and Ghanaians [ 52 ], respectively. Two polymorphisms in two genes ( PSMD6 and C2D4B ) were found to be nonsignificantly associated with T2DM in Black South Africans after correcting for multiple testing [ 53 ]. Polymorphisms in KCNJ11 (rs5219) was found to be nonsignificantly associated with T2DM among Ghanaian [ 49 ] and Nigerian [ 54 ] populations but significant among Mauritanians [ 55 ].…”

Viscoelasticity as a measurement of clot structure in poorly controlled type 2 diabetes patients: towards a precision and personalized medicine approach

“…The world-wide prevalence of cases of type 2 diabetes and pre-diabetes have been spiralling out of control, and not only in developed countries, but also in third-world countries [1–4], with more than half a billion cases expected by 2030 [5]. Co-morbidities are also a major health burden on all health systems, and include hypoglycaemia, hypertension, dyslipidaemia, cardiovascular and heart related deaths, stroke, kidney disease, eye problems and also amputations [6].…”

Systematic Review of Polygenic Risk Scores for Type 1 and Type 2 Diabetes

“…The databases from where the articles were retrieved are shown in Table 1. The studies relied on datasets from different sources: T1DGC [55], WTCCC [56], UFDI, Iranian Hospitals [35], the PURE study [57], UK hospital [45], GoDARTS [58], MPP [59], BPS [60], Framingham…”