Genome-wide association studies on malaria in Sub-Saharan Africa: a scoping review

Abstract

Background: Malaria remains one of the leading causes of death in Sub-Saharan Africa (SSA). The scoping review mapped evidence in research on existing studies on malaria genome-wide association studies (GWAS) in SSA. Methods: A scoping review was conducted to investigate the extent of malaria studies in SSA under GWAS. The review followed the methodology for scoping reviews developed by Arksey and OMalley, including identification of research problems, searching for relevant studies, selecting studies, charting data, collating, summarizing, and reporting the findings. Data from relevant studies were collected and synthesized using Excel and Zotero software. The data collected included information on the author, the years of study, the countries of study, the research areas of interest, and the study designs used. Results: Of an initial pool of over 2000 articles retrieved from four databases, namely Google Scholar, PubMed, Scopus, and Web of Science, 569 were retained. After applying the inclusion-exclusion criteria, 99 articles were found to be relevant. Most of these studies (n=25, 60%) used a case-control study design, while the rest used cross-sectional, cohort, longitudinal, family-based, and retrospective designs. These studies were conducted between 2000 and 2023, with a significant increase observed in 2011. Most studies were carried out in Kenya (n = 25), Gambia (n = 17), Cameroon (n = 15), Ghana (n = 12), and Tanzania (n=11), primarily exploring genetic variants associated with malaria susceptibility, resistance, and severity. Conclusion: Many case-control studies in Kenya and Gambia reported genetic variants in malaria susceptibility, resistance, and severity. Few articles were systematic reviews and scoping reviews. GWAS on malaria is scarce in SSA and even fewer studies are model-based. Consequently, there is a pressing need for more genome-wide research on malaria in SSA.