By running 100 metres in 9.98sec Friday 19-year old French sprinter Christophe Lemaitre not only set a national record, he became the first person genetically of European origin to officially cover the distance in less than 10 seconds.
The breakthough came at the French national athletics championship in the southwestern city of Valence.
Paradoxically, what makes this feat remarkable is not how few athletes have shattered the 10-second barrier but how many: 71, according to an AFP tally.
All but one of these 100m sprinters -- starting with US trailblazer Jim Hines, who clocked 9.95 at the 1968 Mexico Olympics -- have been of recent African origin, overwhelmingly from the western part of the continent.
Before Lemaitre, the one exception was Patrick Johnson, born of an Irish father and an indigenous Australian mother.
The sheer number, and near-monopoly, of under-ten-second performances linked to Africa are more than a simple coincidence or statistical anomaly, say experts.
But exactly what mix factors has led to this outcome remains a puzzle.
"At the highest levels of athletic performance everything matters," said Daniel MacArthur, a researcher at the Institute for Neuromuscular Research at The Children's Hospital at Westmead in Sydney.
"In order to compete against the best of the best, you need to have the right attitude, the right diet, the right training and the right genes," he told AFP.
One explanation that does not hold water, scientists agree, is race.
The idea that the colour of one's skin is somehow related to innate ability is now recognized as an invidious cultural artifact that simply does not correspond to genetic reality.
"Scientifically, it is a discredited notion," said Robert Scott, a researcher at the Institute of Metabolic Science in Cambridge, England who has explored the genetic determinants of elite athletic performance.
"There is more genetic diversity within small areas of east Africa than in most of Europe," he told AFP in an e-mail exchange.
But that does not mean that genes are not an ingredient -- perhaps even the key ingredient -- in the recipe for super-elite sprinters, and the reason so many share west African roots, Scott and others say.
Indeed, a flurry of research in the last decade has uncovered several genetic variants that impact the ability to move with explosive speed.
First on the list is ACTN3, a gene which determines whether the body produces the protein giving rise to so-called "fast-twitch" muscle fibres that have been shown to favour top-level performances in sprinting.
The genes are either locked on or off, which means humans have one of three possible genetic endowments: a double "RR" or single "RX" compliment of fast-twitch producing protein, or the so-called "XX" or "null" variant, which yields none at all.
In non-elite athletes, the gap between having an active or silent variant is imperceptibly small when it comes to performance, studies have shown.
But when the human body nudges against its absolute limits, it can mean the difference between victory or defeat -- or between 10.01 and 9.99 in the 100 metres.
"Of the dozens of Olympic-level sprinters who have been tested for this gene so far, only a few have been found to possess the 'non-sprint' version," said MacArthur.
But the question still remains: why do runners of African origin so thoroughly dominate the top of the game?
Part of the answer, at least, lies in the distribution of these "fast" genes across the globe.
On an evolutionary time scale we are all children of Africa, the cradle of the human species.
But as homo sapiens spread, sub-populations settled and became isolated, resulting in hundreds of genetically concentrated diseases and traits, including ACTN3.
"DNA analysis carried out on 200 Jamaican Olympians ... show that 80 percent have the 'strong' 577RR variant," notes Rachel Irving, a researcher at the University of West Indies and co-author of a recent study examining the genotypes in top-level Jamaican and US sprinters.
Led by world record holder Usain Bolt, Jamaica garnered six gold, three silver and two bronze medals at the Beijing Olympics, all in sprinting events.
Only one-to-two percent of west Africans have the 'weak' XX variant, compared to 18 percent in the United States, 20 percent in Europe and 25 percent in Asia.
