October 21, 2004

Y chromosome haplogroups of elite Ethiopian endurance runners

A new study investigates the occurrence of Y-chromosomal haplogroups in elite Ethiopian endurance runners versus a control sample. The authors discovered that:

Four of the haplogroups (E*, E3*, E3b1 and K*(xP)) show statistically significant differences between one or both of the control populations and some of the athlete groups. E*, E3* and K*(xP) are positively associated with aspects of endurance running, whereas E3b1 is negatively associated.

Paragroups E* and E3* have a Sub-Saharan African distribution, and do not include the E3b clade which is also found outside Africa, or the E3a clade typical of Bantu speakers. Clade E3b1 which is negatively associated with endurance running is the main subclade of haplogroup E represented in Europe. Paragroup K*(xP) is likely of Eurasian origin.

The authors go to some lengths to ensure that the differential representation of these haplogroups in endurance runners is not due to the fact that they are drawn from an ethnolinguistic subpopulation with different Y-chromosomal distributions. Thus, they propose that it may be the case that some genes on the Y chromosome may affect endurance running performance.

Human Genetics (Online First)

Y chromosome haplogroups of elite Ethiopian endurance runners

Colin N. Moran et al.

Abstract Favourable genetic endowment has been proposed as part of the explanation for the success of East African endurance athletes, but no evidence has yet been presented. The Y chromosome haplogroup distribution of elite Ethiopian athletes (n=62) was compared with that of the general Ethiopian population (n=95) and a control group from Arsi (a region producing a disproportionate number of athletes; n=85). Athletes belonged to three groups: marathon runners (M; n=23), 5–km to 10–km runners (5–10K; n=21) and other track and field athletes (TF; n=18). DNA was extracted from buccal swabs and haplogroups were assigned after the typing of binary markers in multiplexed minisequencing reactions. Frequency differences between groups were assessed by using contingency exact tests and showed that Y chromosome haplogroups are not distributed amongst elite Ethiopian endurance runners in the same proportions as in the general population, with statistically significant (P<0.05) differences being found in four of the individual haplogroups. The geographical origins and languages of the athletes and controls suggest that these differences are less likely to be a reflection of population structure and that Y chromosome haplogroups may play a significant role in determining Ethiopian endurance running success.


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