Turkana carrying water back to their households (photo credit Michel Mata)<\/figcaption><\/figure>\nThe genomic analysis found eight regions of DNA that had undergone natural selection, but one gene, <\/span>STC1<\/span><\/i>, stood out with exceptionally strong evidence of selection. STC1 is expressed in the kidneys and plays two vital roles that directly reflect the ecological challenges of both arid living and pastoralism. First, it helps the body conserve water by responding to antidiuretic hormone, allowing the Turkana to concentrate their urine and retain more water. Second, it may also play a role in protecting the kidneys from the waste generated by purine-rich foods like red meat. These waste products, such as urea and uric acid, must be filtered by the kidneys and in many people, too much dietary purine can lead to gout; a problem that appears to be rare among the Turkana.<\/span><\/p>\nAncient Climate, Modern Genetics<\/b><\/p>\n
Intriguingly, the timing of these genetic adaptations appears to coincide with the aridification of northern Africa, suggesting that as the climate became increasingly dry about 5,000 years ago, natural selection favored genetic variants that enhanced survival in desert conditions. This finding provides a compelling example of how human populations have evolved in direct response to major environmental changes. The genetic analyses show that these changes are also present in neighboring groups, including the Rendille, who live in this arid environment. <\/span><\/p>\n“This research demonstrates how our ancestors successfully adapted to dramatic climate shifts through genetic evolution,” noted Dr. Epem Esekon, the County Executive for Health and Sanitation in Turkana County, Kenya.\u00a0<\/span><\/p>\nWhen Evolution Meets Urbanization<\/b><\/p>\n
But the story doesn’t end in the desert. As more Turkana migrate to towns and cities, a striking pattern emerges: the very genetic traits that aid survival could now carry hidden costs. This phenomenon, known as <\/span>evolutionary mismatch<\/span><\/i>, occurs when adaptations shaped by one environment become liabilities in another.<\/span><\/p>\nBy comparing biomarkers and gene expression in the genomes of city-dwelling Turkana compared to their pastoral kin, the researchers found an imbalance of gene expression that may predispose them to chronic diseases, such as hypertension or obesity, which the researchers have also found to be more common in urban settings, where diets, water availability, and activity patterns are radically different.<\/span><\/p>\n\u201cWith more people shifting from rural to urban lifestyles, we are also seeing a change in disease patterns,\u201d said the Acting Director General, KEMRI, Prof. Elijah Songok.<\/span><\/p>\n“Understanding these adaptations will guide health programs for the Turkana\u2014especially as some shift from traditional pastoralism to city life,” said Charles Miano, one of the study’s coauthors and a graduate student at the Kenya Medical Research Institute (KEMRI) in Nairobi.<\/span><\/p>\nThe study has health implications for many traditional cultures in Africa and around the world that are having to adapt to rapidly changing environments or adopt urban lifestyles. Evolutionary mismatch likely leads to high rates of “lifestyle” diseases around the world, such as diabetes, coronary artery disease and high blood pressure.<\/span><\/p>\n“This study highlights how working with transitioning populations can lead to new models for understanding how present-day environments interact with past adaptations to potentially impact modern day disease risk,” added Lea.<\/span><\/p>\nThe Turkana Health and Genomics Project: A Partnership in Discovery<\/b><\/p>\n
This story began not in a laboratory, but around desert campfires. Many of the questions this research addresses were generated during long meetings with the Turkana community, facilitated by the Turkana Health and Genomics Project (THGP), a long-term collaboration between Kenyan and U.S.-based researchers. From its earliest days, the project has centered on the co-production of knowledge, combining genomic science with traditional ecological and anthropological expertise. The research agenda emerged from dialogue with Turkana elders, scientists, and community members, conversations about health, diet, and change, often shared in the evening around a camp fire.<\/span><\/p>\n“Working with the Turkana has been transformative for this study,” said Sospeter Ngoci Njeru, one of the THGP’s leaders and deputy director of KEMRI’s Centre for Community Driven Research. “Their insights into their environment, lifestyle and health have been essential to connecting our genetic findings to real-world biology and survival strategies.”<\/span><\/p>\nLessons for a Changing World and Giving Back<\/b><\/p>\n
As the world faces rapid environmental change, the Turkana’s story offers both inspiration and practical insights. For generations, this community has developed and maintained sophisticated strategies for surviving in a challenging and variable environment, knowledge that becomes increasingly valuable as climate change creates new survival challenges globally.<\/span><\/p>\nThe research team is now creating a podcast in the native Turkana language that will not only share the study’s findings in accessible ways but also will offer the community practical health considerations that arise with rapid lifestyle transitions, combining scientific insights with knowledge from within the community. In conversations with Turkana study communities, we are seeing that the study findings resonate with people\u2019s\u00a0 perceptions about their capacity to go without water for long, but they also noted that other pastoralists in the region like the Rendille, Samburu, Borana, Merille, Karimojong, and Toposa are likely to share this adaptation due to living in similarly arid environments.\u00a0 <\/span><\/p>\n“I am deeply inspired by the fact that this work places the Turkana and sub-Saharan Africa at the forefront of genomic research, a field where indigenous populations have historically been underrepresented,” Miano said. \u201cWorldwide, indigenous communities like the Turkana are essential partners in advancing our knowledge of human resilience,\u201d said Dr. Dino Martins, Director, Turkana Basin Institute. \u201cTheir experience provides lessons for how climate and environmental changes continue to shape human biology and health.\u201d<\/span><\/p>\nCitation: Lea, AJ, IV Caldas, KM Garske, ER Gerlinger, JP Arroyo, J Echwa, M Gurven, C Handley, JC Kahumbu,\u00a0 J Kamau, P Kinyua, F Lotukoi, A Lopurudoi, S Lowasa, SN Njeru, R Mallarino, D Martins, PW Messer, C Miano, B Muhoya, J Peng, T Phung, JD Rabinowitz, A Roichman, R Siford, AC Stone, AM Taravella Oill, S Mathew, MA Wilson, JF Ayroles. Adaptations to water stress and pastoralism in the Turkana of northwest Kenya. 2025. Science.<\/em><\/p>\nFunding Statement: This work was funded by internal awards from Princeton University, The John Templeton Foundation (grant #48952), and The National Institute of General Medical Sciences of the National Institutes of Health (R35GM124827 and R35GM147267). It was also supported, in part, by the Intramural Research Program of the National Human Genome Research Institute, National Institutes of Health, The Graduate College at Arizona State University, The Achievement Rewards for College Scientists Foundation Phoenix Chapter as a Pierson Scholar, and Arizona State University Sigma Xi. Lea was also supported by the Helen Hay Whitney Foundation, a Searle Scholars Award from the Kinship Foundation, and an Azrieli Global Scholars Award from the Canadian Institute for Advanced Research.<\/p>\n","protected":false},"excerpt":{"rendered":"
Originally posted by UC-Berkeley team, edits by Andy Flick Evolutionary Studies scientific coordinator Scientists Discover Key Genetic Adaptations in Partnership with Turkana Pastoralists of Northern Kenya Groundbreaking study reveals how thousands of years of natural selection shaped remarkable adaptations to an extreme environment. Through a collaboration between US and Kenyan researchers and Turkana communities of…<\/p>\n","protected":false},"author":2421,"featured_media":3664,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"spay_email":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false,"jetpack_publicize_feature_enabled":true},"categories":[7],"tags":[28,13,14,16,128,15,3,177,176],"acf":[],"yoast_head":"\n \n \n \n \n \n \n \n \n \n \n \n\t \n\t \n\t \n \n \n\t \n\t \n\t \n