Genetic aspects of athletic performance: the African runners phenomenon

Abstract

The current dominance of African runners in long-distance running is an intriguing phenomenon that highlights the close relationship between genetics and physical performance. Many factors in the interesting interaction between genotype and phenotype (eg, high cardiorespiratory fitness, higher hemoglobin concentration, good metabolic efficiency, muscle fiber composition, enzyme profile, diet, altitude training, and psychological aspects) have been proposed in the attempt to explain the extraordinary success of these runners. Increasing evidence shows that genetics may be a determining factor in physical and athletic performance. But, could this also be true for African long-distance runners? Based on this question, this brief review proposed the role of genetic factors (mitochondrial deoxyribonucleic acid, the Y chromosome, and the angiotensin-converting enzyme and the alpha-actinin-3 genes) in the amazing athletic performance observed in African runners, especially the Kenyans and Ethiopians, despite their environmental constraints.

Keywords: endurance runners; genes; genotype; physical exercise.

Figure 1

Genes associated with elite athletic performance. Notes: (A) ACE gene polymorphism. Researchers have investigated the presence or absence of a variant in intron 16 of chromosome 17 on the ACE gene. (B) ACTN3 gene polymorphism. The presence or absence of the variant R577X, on chromosome 11 in the ACTN3 gene, was studied in relation to the status of elite athletes. Data taken from Wilber RL et al, Scott RA, et al, Rankinen T, et al, Arden Nk, et al and Lippi G et al. ,,,, Abbreviations: ACE, angiotensin converting enzyme; ACTN3, alpha-actinin-3; D, deletion; I, insertion.