Posted By: Sara Cullinan, PhD, Deputy Editor, AJHG
Each month, the editors of The American Journal of Human Genetics interview an author of a recently published paper. This month we check in with Enock Matovu to discuss his paper “High Levels of Genetic Diversity within Nilo-Saharan Populations: Implications for Human Adaptation”.
AJHG: What prompted you to start working on this project?
Enock: I have for years worked with human African trypanosomiasis, one of the neglected tropical diseases (NTDs) that has for centuries afflicted millions across sub-Saharan Africa. One intriguing fact is that not all exposure to the causative parasites (Trypanosomes) necessarily leads to disease; some individuals are able to tolerate, others exhibit mild symptoms, yet others get severe disease inevitably leading to death. It is therefore arguable that there must be a host genetic basis for these differences in response to infection; with some polymorphisms conferring protection to affected individuals while other facilitate fast evolution into full-blown disease. Previous studies have mainly concentrated on parasite diversity, completely ignoring the plausible role of host genetics in disease phenotypes. I wanted to understand the genetics of human trypnotolerance as a starting point to devise alternative approaches to control of this NTD.
Then came the Human Heredity and Health in Africa (H3Africa) initiative, funded by the NIH and Wellcome, to support population-based studies for a better understanding of how the interplay between human genes and the environment influence disease susceptibility, pathogenesis and prevention, with the goal of improving the health of African populations. This was a wonderful opportunity to team with renowned scientists across Africa and beyond, to investigate the role of human genetics in susceptibility to human African trypanosomiasis.
AJHG: What about this paper/project most excites you?
Enock: This project meant that we were about to study the genetic diversity of many African populations. Our consortium alone is spread across 8 countries and we could analyze dozens of communities from these countries. In addition, we could access data from other H3A consortia (presently about 48) working with both communicable and non-communicable disease, as well as data already in public databases from previous sequencing projects. No platform could provide such wide access to the indisputably high genetic diversity across the Africa continent.
As we comparatively analyzed data for diversity, even before relating it to disease phenotypes, we come across this very high diversity from a hitherto unstudied ethnic group that we definitely had to publish and make known to for the entire community of human geneticists. We demonstrated presence of selective sweeps that enable the human race to adapt to the environments where they live, in this case the Sahel region where the studies ethnic group originated.
AJHG: Thinking about the bigger picture, what implications do you see from this work for the larger human genetics community?
Enock: The key to global health solutions lies in studying and exploiting the genetic diversity across Africa to identify genetic predispositions to disease or otherwise. This approach will facilitate identification of genes or biochemical pathways involved in different conditions. Such pathways can be enhanced or inhibited (depending on their mechanisms of action that bring about disease) to provide better health for the affected individuals. New tools such as supportive therapy involving boosters or inhibitors, including food supplements, should be developed as adjuvants to classical chemotherapy that largely ignores the host and solely concentrates on the causative agents. I think in this case not even the sky can be the limit.
AJHG: What advice do you have for trainees/young scientists?
Enock: Never give up; follow your passion right to the end. Only cease when you have reached a conclusive end.
AJHG. And for fun, tell us something about your life outside of the lab.
Enock: I am a family man, living in a semi-rural-semi-urban area. With a farmer’s upbringing, I tend to a few animals as a hobby: some chickens, goats, a few cows. I love that occupation away from the hectic life of science, when I don’t have to use so much brain power.
Enock Matovu, PhD is an Associate Professor at Makerere University, Kampala, Uganda. He has been a member of ASHG since 2020.