biostudies-literatureMcQuillan MAUniversity of Pennsylvania Center of Excellence in Environmental ToxicologyNIDDK NIH HHSUniversity of PennsylvaniaNIEHS NIH HHSAmerican Diabetes AssociationNational Institutes of HealthNIGMS NIH HHS927-938https://www.ebi.ac.uk/biostudies/studies/S-EPMC11080607biostudies-literatureUnknown111(5)Leukocyte telomere length (LTL) varies significantly across human populations, with individuals of African ancestry having longer LTL than non-Africans. However, the genetic and environmental drivers of LTL variation in Africans remain largely unknown. We report here on the relationship between LTL, genetics, and a variety of environmental and climatic factors in ethnically diverse African adults (n = 1,818) originating from Botswana, Tanzania, Ethiopia, and Cameroon. We observe significant variation in LTL among populations, finding that the San hunter-gatherers from Botswana have the longest leukocyte telomeres and that the Fulani pastoralists from Cameroon have the shortest telomeres. Genetic factors explain ∼50% of LTL variation among individuals. Moreover, we observe a significant negAmerican journal of human geneticsAssociation between telomere length and Plasmodium falciparum malaria endemicity in sub-Saharan Africans.PMC11080607T32-ES019851R35 GM134957-01P30 DK019525R35 GM134957T32 ES0198511-19-VSN-02Chanock SJNjamnshi AKHansen MEBMcQuillan MAMeskel DWTishkoff SAFokunang CBeggs WVerhulst SAviv ANyambo TMpoloka SWMokone GGBelay GfalseAssociation between telomere length and Plasmodium falciparum malaria endemicity in sub-Saharan Africans.Leukocyte telomere length (LTL) varies significantly across human populations, with individuals of African ancestry having longer LTL than non-Africans. However, the genetic and environmental drivers of LTL variation in Africans remain largely unknown. We report here on the relationship between LTL, genetics, and a variety of environmental and climatic factors in ethnically diverse African adults (n = 1,818) originating from Botswana, Tanzania, Ethiopia, and Cameroon. We observe significant variation in LTL among populations, finding that the San hunter-gatherers from Botswana have the longest leukocyte telomeres and that the Fulani pastoralists from Cameroon have the shortest telomeres. Genetic factors explain ∼50% of LTL variation among individuals. Moreover, we observe a significant neg2024-01-01T00:00:00Z2024 May2026-06-02T04:08:39.005Z2025-04-21T21:44:30.792ZS-EPMC110806073870174510.1016/j.ajhg.2024.04.003