Genetic differentiation in East African ethnicities and its relationship with endurance running success

Abstract

Since the 1960s, East African athletes, mainly from Kenya and Ethiopia, have dominated long-distance running events in both the male and female categories. Further demographic studies have shown that two ethnic groups are overrepresented among elite endurance runners in each of these countries: the Kalenjin, from Kenya, and the Oromo, from Ethiopia, raising the possibility that this dominance results from genetic or/and cultural factors. However, looking at the life history of these athletes or at loci previously associated with endurance athletic performance, no compelling explanation has emerged. Here, we used a population approach to identify peaks of genetic differentiation for these two ethnicities and compared the list of genes close to these regions with a list, manually curated by us, of genes that have been associated with traits possibly relevant to endurance running in GWAS studies, and found a significant enrichment in both populations (Kalenjin, P = 0.048, and Oromo, P = 1.6x10-5). Those traits are mainly related to anthropometry, circulatory and respiratory systems, energy metabolism, and calcium homeostasis. Our results reinforce the notion that endurance running is a systemic activity with a complex genetic architecture, and indicate new candidate genes for future studies. Finally, we argue that a deterministic relationship between genetics and sports must be avoided, as it is both scientifically incorrect and prone to reinforcing population (racial) stereotyping.

Exome-Wide Association Study of Competitive Performance in Elite Athletes

“…Like the present study, a study in diverse populations conducted in the literature reported that none of the SNPs reached genome-wide significance with the endurance athlete status [ 14 ]. Nonetheless, others reported the associations of the specific SNPs with different exercise-related parameters [ 15 , 16 , 17 , 45 , 46 , 47 , 48 ]. However, the number of participants in those studies was increased by the involvement of the athletes from close countries.…”

Adolescent athletes have better general than sports nutrition knowledge and lack awareness of supplement recommendations: a systematic literature review

“…In this review, several regions were underrepresented, with Brazil being the only country included from South America, Australia the only country from Oceania and no countries included from Africa. The lack of representation in African countries appears disproportionate when considering the number of athletes from this region; for example, endurance running is dominated by Ethiopian and Kenyan athletes ( 68 ) . The lack of funding in this region may explain the absence of studies in this region.…”

Beyond the border of the athlete-centered approach: a model to understand runners' performance

“…Narratives about genetic characteristics, morphology, and physiological parameters (i.e., maximum oxygen consumption, metabolic efficiency, and hematological parameters) were debated for many years (Wilber and Pitsiladis, 2012 ; Tucker et al, 2013 ). However, a recent comparative study investigating the relationships between ethnicities (Kalenji's—Kenya and Oromo—Ethiopia) and endurance running success concluded that causality inferences regarding the relationship between genetics and sports must be avoided, once it is both scientifically incorrect and prone to reinforcing population (racial) stereotyping (Hamilton, 2000 ; Zani et al, 2022 ). With this conclusion, the authors do not exclude the role of genetics but reinforce the importance to move forward.…”

“…In the context of endurance running, aside from genetic, morphological, physiological, and training characteristics that contribute to the African runner's phenomenon (i.e., Kenya, Ethiopia) (Larsen, 2003 ; Zani et al, 2022 ), the country's historical background, the population's lifestyle characteristics, the economic development, and perspectives of social ascension and/or better living conditions through the sport need to be considered as factors related to the running training engagement and performance (Bale and Sang, 1996 ). For example, colonization, religious missions, and school policies were important agents in the dissemination of running in the Kenyan context.…”

“…As a dynamic, non-linear, and multidimensional phenotype, there seems to exist a consensus that athletes' performance should be investigated through a holistic approach (Balague et al, 2013 ; Balagué et al, 2017 ). However, the athlete-centered approach (Midgley et al, 2007 ) overvalues individual characteristics, such as physiology, psychology, genetics, and biomechanics, as the key factors to understand athletes' performance (Moir et al, 2019 ; Zani et al, 2022 )—dominating the scientific debate for a long time.…”