Major Project Expands African Genomic Diversity with 1,000+ Samples

A groundbreaking initiative called the Assessing Genetic Diversity in Africa (AGenDA) has successfully generated whole-genome sequence data from over 1,000 individuals across multiple African nations. This collaborative effort involves nine countries and aims to enhance the understanding of human genetic diversity, which is crucial for insights into various health issues, including cancer, mental illness, diabetes, and heart disease. The findings are set to have a significant impact on health systems globally.

The AGenDA project, as outlined in a recently published paper in Nature, focuses on communities that have historically been underrepresented in genomic databases. The initiative encompasses diverse populations, including hunter-gatherers, Nilo-Saharan and Afro-Asiatic speakers, understudied Bantu groups, and communities from North Africa and the Indian Ocean islands. The project has been coordinated from South Africa, with participants recruited from countries such as Angola, the Democratic Republic of Congo, Kenya, Libya, Mauritius, Rwanda, Tunisia, and Zimbabwe.

Professor Michèle Ramsay, Director of the Sydney Brenner Institute for Molecular Bioscience (SBIMB) at Wits University and lead author of the study, emphasized the significance of this work: “Most genomic datasets that are used to predict disease risk come from people of European origin. As a result, the genetic ‘patterns’ guiding modern medicine are very Eurocentric and poorly predict diseases in African populations.” The AGenDA project is designed to address this disparity by increasing the representation of African genomic data in global datasets.

The genetic diversity found in African genomes is notably greater than that of any other continent. For instance, two individuals from different African regions can exhibit more genetic variation than a European and an Asian. This lack of African data in genetic research can lead to inaccuracies in risk predictions for diseases prevalent in African populations.

Dr. Furahini Tluway, AGenDA Project Coordinator at SBIMB and a co-author of the study, remarked, “AGenDA is about correcting that imbalance so that genetic research and resulting medical interventions work for African people and for the world.” The project aims to create rich reference data through whole genome sequencing, which can be utilized by scientists globally.

The technical implications of this research are significant. Professor Scott Hazelhurst, head of bioinformatics at SBIMB, explained that genome-wide association studies (GWAS) rely on recognizing DNA patterns that can differ considerably across populations. Without adequate African data, risk-prediction models may be biased and inaccurate for African patients. “By expanding African genome reference data, AGenDA is making GWAS more scientifically robust and more ethically sound,” he stated.

AGenDA also aims to set a precedent in research governance. The project is led by African scientists, and data sharing is overseen by African-based committees that determine how the data can be used. Communities are actively engaged before sampling begins, and consent processes are tailored to local languages and cultures. This approach ensures that participants are partners in the research process, protecting their rights and promoting ethical standards.

This initiative builds on over a decade of African-led genomic science through the Human Heredity and Health in Africa (H3Africa) Consortium. H3Africa is a pan-African initiative focused on strengthening genomic research capacity on the continent and ensuring that African populations benefit from genomic medicine. The consortium has supported numerous large-scale studies, trained scientists, and established significant genomic resources that are now in use worldwide.

One notable resource is AWI-Gen (Africa Wits-INDEPTH Partnership for Genomic Studies), which investigates the genetic and environmental factors contributing to cardiometabolic diseases in African populations. Dr. Ananyo Choudhury, co-lead for AGenDA and a senior scientist at SBIMB, highlighted the importance of selecting diverse populations for sequencing in genomic studies. He noted that the traditional approach has often resulted in significant gaps in representation, particularly in terms of geography and ethnolinguistic diversity.

Looking ahead, the data generated by AGenDA will contribute to the development of African genetic reference databases that can be used for disease research, genetic testing, and medicine worldwide. As these databases grow, they will enhance the accuracy of research on diseases that significantly impact African populations, ultimately improving global medical science.

Professor Ramsay concluded, “Because African genomes contain the deepest branches of human genetic history, they help scientists distinguish genetic variants that are ancient from those that arose more recently and help to detect variants that truly influence disease. Studying African diversity improves genetic science for everyone.”

This extensive project not only aims to fill existing gaps in genomic research but also ensures that African populations have a voice in the ongoing evolution of medical science and genetic research.