'Endurance runs in the genes'

Sydney, Jan 13 (UNI) Scientists have come up with a genetic explanation at to why some people naturally exceed in long-distance marathon events while others perform better in short races.

Researchers from the University of Sydney have analysed that people with the mutant form of a gene called alpha-actinin-3 (ACTN3) have superior endurance helping them to excel in marathon running and rowing while those with the normal form of gene fare well in sprint events.

The research published in the journal Human Molecular Genetics is the first to explain such variation , the Daily Telegraph reported.

People with the normal form of the gene produce a protein in their so-called fast-twitch muscle fibres called alpha-actinin-3 which allows them to generate the rapid contractions needed in sprinting and cycling, reserachers explained.

After conducting the reserach on mice , they found that those with the mutant form of the gene had superior endurance, but were not able to produce explosive bursts of power.

''We can now explain how this common genetic variation influences athletic performance, as well as why it has become so common in the general population,'' one of the researchers, Professor North said.

They also studied the evolution of the mutant form of the ACTN3 gene in humans, showing it arose during the last ice age and rapidly increased in Europe and Asia thanks to natural selection.

Prof North said this suggested that the genetic variant provided a fitness advantage to our ancestors.

''There is a fascinating link between factors that influence survival in ancient humans and the factors that contribute to athletic abilities in modern man,'' she said.

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