GHES LMIC Fellow 2017-2018
Home Institution: University of the Witwatersrand, Johannesburg, South Africa
US Institution: Stanford University
Project Title: Gut Microbiome Characterization in South African Populations
Numerous bodily habitats exist in humans, many of which are colonized by a diverse range of microbes. These microbes carry 10-100 times more genes than the human genome and exist in different relationships in different individuals; presumably to ensure the normal functioning of the host. This community of microorganisms in the human body is referred to as the microbiome (microbiota). The majority of these microorganisms are found in the gastrointestinal tract (gut).
Research efforts so far have provided insight into host-microbe interactions and shown the impact of various diets and lifestyles on the composition of an individuals intestinal microbiota. Only a handful of these studies have been done on African populations. Those that have been published have highlighted noticeable differences in the relative abundance of constituents in the gut microbiome of neighbouring African populations and these differences were attributed to varied diets and lifestyles. When comparing the gut microbiome of Africans to their Western counterparts, the African gut is relatively more diverse in taxonomic composition. These compositional differences can loosely be attributed to the health status, basic diet, environment, age and lifestyle of the host.
Alterations to the infant and early-life gut microbiota compositions have been observed in obesity, type 2 diabetes and other comorbid conditions, as well as in immunological and inflammatory diseases. This seemingly rapid plasticity of the gut under different physiological conditions makes the understanding of region- and group-specific microbiomes imperative. The diverse ethnicities in South Africa provide a great opportunity to gain more insight into the human microbiome.
This study forms a part of the H3Africa, NIH-funded AWI-Gen project exploring genomic and environmental risk factors associated with cardiometabolic disease in African populations. It will focus on the profiling of the gut microbiome of individuals in AWI-Gen sub-cohorts in an urban location: Soweto (coordinated within the South African Medical Research Councils Developmental Pathways for Health Research Unit, DPHRU), and a rural location: the Agincourt health and socio-demographic surveillance system (Mpumalanga). The representative ethno-linguistic groups across both sites include Zulu, Xhosa, Ndebele, Sotho, Venda, Tsonga, Tswana, BaPedi and Swati.
This study is expected to serve as a baseline for future microbiome and metagenomics research. The objectives include: characterizing the microbiome composition and community structure in the cohorts, and exploring the association between cardiometabolic disease risk factors and metagenomic profiles through phylogenetic analyses.