Genomic and Environmental Risk Factors for Cardiometabolic Disease in Africans

Principal Investigator: Michèle Ramsay          
Co-Principal Investigator: Osman Sankoh

Institutes: National Health Laboratory Services, University of the Witwatersrand, Johannesburg, South Africa  and INDEPTH, Ghana 

 Scientific Description: The long-term vision of the Collaborative Centre (CC) is to build sustainable capacity in Africa for research that leads to an understanding of the interplay between genetic, epigenetic and environmental risk factors for obesity and related cardiometabolic diseases (CMD) in sub-Saharan Africa. The CC will be consolidated under the auspices of the University of the Witwatersrand (Wits) and the International Network for the Demographic Evaluation of Populations and Their Health in Developing Countries (INDEPTH). It will capitalize on the unique strengths of existing longitudinal cohorts, including the urban Soweto and rural Agincourt studies in South Africa (Wits based), and the well established INDEPTH demographic health and surveillance centers in Kenya, Ghana, Burkina Faso and South Africa. The centers offer established infrastructure, trained fieldworkers, long-standing community engagement, and detailed longitudinal phenotypic data, focusing on obesity and cardiometabolic health. Key strengths are harmonized phenotyping across sites, building on strong existing cohorts, and representation of the geographic and social variability of African populations. We aim to: 1. Build sustainable infrastructure (biobanks and laboratories) and capabilities (well characterized population cohorts, genotyping and bioinformatics) for genomic research on the African continent; 2. Understand the genomic architecture of sub-Saharan populations from west, east and south Africa to guide genomic studies (genome sequencing and high throughput SNP and CNV arrays using unrelated individuals and family trios to improve the accuracy of haplotype analyses) and; 3. Investigate the independent and synergistic genomic contributions to body fat distribution (BMI, hip/waist circumference, subcutaneous and visceral fat) in these populations considering the relevant environmental and social contexts (rural/urban communities, quickly transitioning obesity prevalence, differential HIV, TB, and malaria infection histories). We will investigate the effect of obesity and fat distribution on the risk for CMD in the longitudinal cohorts. The CC will draw upon a wide group of highly experienced African scientists and international collaborators to ensure the success of its vision.

Lay Description: This Wits-INDEPTH H3Africa Collaborative Centre (CC) under the leadership of Drs. Michèle Ramsay and Osman Sankoh aims to study the genetic and environmental risk factors for obesity and related cadiometabolic diseases (CMD). It is a partnership between the University of Witwatersrand and the International Network for the Demographic Evaluation of Populations and Their Health in low- and middle-income countries (INDEPTH), using five INDEPTH member health and demographic surveillance system (HDSS) field sites across four African countries, Ghana, Burkina Faso, Kenya and South Africa, as well as an urban study site in Soweto. The study will begin by examining the genetic architecture of these African populations and will progress to investigate genomic contributions to body fat distribution, considering the relevant environmental and social contexts, in order to contribute to an understanding of cardiometabolic disease susceptibility.