WEDNESDAY, Sept. 27, 2006 (HealthDay News) -- Superior athletic ability may, literally, be at your fingertips.
British researchers have deduced that women whose ring fingers are longer than their index fingers achieve higher levels in sports, particularly running, soccer and tennis.
So when trying to spot a future Venus Williams or Mia Hamm, coaches and parents might do well to add finger length to the list of promising attributes, says study author Dr. Tim Spector, a professor of genetic epidemiology at Kings College London whose report currently appears online in the British Journal of Sports Medicine.
The finding also opens the door to exploring how seemingly unrelated attributes may be linked through shared genes.
Previous research had found an apparent link between this finger ratio in males and various traits including fertility, intellectual ability, sexual orientation and athletic prowess.
Again, men who achieved high sporting levels, especially runners and skiers, had longer ring fingers vs. index fingers. And homosexual men tended to have shorter ring fingers.
This pattern was thought to be due to excess testosterone levels in the womb.
A few studies in females had made similar conclusions, but the numbers were small, and the evidence unconvincing. "I'd seen this data and was actually intrigued, but I didn't believe it," Spector said. "I thought it was bias."
Spector, however, had the ability to test the hypothesis at his own fingertips, courtesy of a registry of twins whose fingers had been X-rayed as part of a study involving the genetics of arthritis.
"We had a precise way of measuring finger length very quickly," Spector explained.
These measurements were then compared in identical female twins vs. non-identical twins.
Participants were also asked to rank their highest achievement in 12 different sports.
As it turned out, there was also a strong relationship to sports achievement. "The longer the ring finger, the more likely they were to compete at high levels, especially in running, soccer and tennis," Spector said.
And most of the variation appeared due to genes.
"Identical twins were over 90 percent similar in terms of finger length, and the study showed us that there was very little influence of shared environment which would have included the womb environment," he said. "This went against the current theory that this is just due to testosterone levels."
But there's no clear explanation for the finding. "No one knows why," Spector said. "The most likely thing is that it's a marker of genes that are important in sporting prowess and quite why the finger has turned up as this important marker is quite perplexing, really."
But the data raises the possibility that there may be other such markers.
"This tells us that there might be lots of things we can observe in the body that are telling us things about other parts of the body," Spector said. "The fact that you can look at a baby's hands and, just from the proportions of the bones of the fingers, get an idea of what's going on elsewhere in the body is an intriguing observation."
And the pattern is not likely to be limited to finger length. It could be the size of the ear lobes, toe length or whether someone is knock-kneed or bow-legged.
"All these little things could be telling something about developmental genes or things that influence personality and competitiveness," Spector said.
More information
The Women's Sports Foundation has more on female athletes.
