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Defining the Fairest Sex




Watch Dr. Vilain's talk here.



By Veronica Meade-Kelly

If there is one thing nearly all sports aficionados would agree on, it’s that competition should be fair. That's why games have rules, after all. But what happens when the very rules designed to level the playing field aren't fair to everyone? And what if "fairness" itself is illusory?

Perhaps nowhere in sport are these questions more pressing than in elite women's athletics, where a number of high-profile cases have challenged not only the notion of equity in sports, but also the perception of what it means to be a woman.

Eric Vilain, MD (RES ’98, FEL ’99), PhD, director of UCLA's Center for Gender-Based Biology, addressed the issue in a TEDxUCLA talk in July 2014. He is a scientific advisor to the International Olympic Committee (IOC), where he helps tackle one of the most complex issues in sports today: how to define the female category at the highest levels of women's athletics. The problem, he says, is that the male/female divide isn't as clear-cut as it may seem.

Women's sports exist as a separate category largely because male physiology — particularly, levels of the sex hormone testosterone — confers a physical advantage that makes open competition among the sexes inherently unfair. Men, on average, produce 10-to-35 nanomoles of the muscle-building hormone per liter of blood, while women average less than 3 nanomoles per liter.

But there are intermediaries between those two poles, and many individuals (as many as one in 100, some say) don’t fit neatly into the male or female category. That means that some individuals who are born and raised as females — and therefore may take part in women’s athletics — naturally bear masculine traits. A small fraction are born with the male XY sex chromosomes; others carry genetic variants that give them features such as ambiguous genitalia, a mix of male and female gonadal tissue or abnormally high male-hormone levels. These intermediate conditions — often grouped together as “differences or disorders of sex development” (DSD), or "intersex" — blur the dividing line between the only two categories offered in competitive athletics.

But do these variations necessarily give intersex participants an advantage in competitive sports? “Probably,” Dr. Vilain says. But, he notes, genetic advantages are not all that uncommon in sports. “Elite sports are inherently unfair, and athletes who are very special are a little bit genetic oddities," he says.

Recent genetic studies have shown that individuals with mutations in the myostatin (MSTN) gene can amass up to twice the muscle of “normal” humans, and certain variations of the ACTN3 gene, which influences the development of fast-twitch muscle fibers, have been linked to elite sprint performance.

And other, more obvious genetic advantages are not just permitted but are institutionalized. A quick look across the athletic landscape will tell you that height — one of the most complex, heritable traits — often is a defining feature. Small-statured jockeys and gymnasts have a competitive advantage in their sports, while basketball is the play land of giants. That, of course, isn't to say that training, resources and drive don’t play a role in athletic success; there are certainly exceptional athletes who succeed despite the odds, and some with natural advantages who can’t quite make the cut. (Paul Sturgess, at 7 feet 8 inches tall, is the world’s tallest pro basketball player, but he has yet to make it to one of the big-time teams. After playing for the Harlem Globetrotters, he now spends his time largely riding the bench for an NBA development team.) But the preternatural size of a talent like Shaquille O’Neal, while not deterministic, certainly lends an advantage to the peculiarly endowed.

"There are a lot of genetic conditions that confer advantages in athletics,” Dr. Vilain points out, “but there are no different categories for each genetic variant. Everyone plays together and sports celebrates natural ability, which is a politically correct way of saying sports celebrates genetic inequalities."

But the case of women’s athletics is a little different. Given the social and financial rewards that accompany athletic success, sports' governing bodies have historically gone to great lengths to ensure that those competing as women are indeed “female.” Though originally meant to keep men posing as women from competing, restrictions have evolved over time to address intersex cases. Dr. Vilain says organizers have felt the need to devise a threshold of femininity to maintain what they see as the integrity of the games.
At one time, that meant genetic testing. Throughout much of the 20th century, competitors were given cards that amounted to certificates of authenticity, verifying that they indeed carried two X chromosomes. Those without this certification were barred from competition.

At TEDxUCLA, Dr. Vilain shared the story of María Martínez-Patiño, one of Spain's most promising track stars of the early 1980s. An exceptional hurdler, Martínez-Patiño had her world turned upside down when a genetic test revealed she carried XY chromosomes. She would later learn that she had complete androgen insensitivity syndrome, a condition that made her cells unresponsive to male hormones. Though she was completely female in appearance, and had always thought of herself as such, she was ruled ineligible to compete and saw her records, titles and career stripped away.
Her story triggered changes, and sex testing was banned by the start of the 2000 Sydney Olympics. But a new threshold of femininity was created. Currently, that limit is based on testosterone levels, and is set by the IOC at the lower end of the normal male range. The new dividing line allows for genetic variance, and recognizes intersex cases — but only to a degree. Some athletes have still found themselves on the other side of the divide.

Dutee Chand, an Indian sprinter, has challenged her ban by the International Association of Athletics Federation (IAAF) — track’s governing body. The 18-year-old has hyperandrogenism, which causes her to produce levels of testosterone that put her over the limit set by the IAAF and IOC. The rules hold that she can return to competition if she lowers her testosterone levels by taking hormone-suppressing drugs or undergoing body-altering surgery, but Chand has refused.

A New York Times article on Chand reported that others facing the same choice — including four female athletes flagged for testing during the 2012 London Olympics — have complied. Some worry that these women may have also been steered into additional and unnecessary “feminizing” surgeries, and that the process may have been coercive. These women risk losing their livelihoods if they refuse to alter their bodies. They also face stigma, not only for being a "cheat" but also for being something indefinable — not "female." Women who have been "outed" in this way have been publicly shamed in the media, and have lost not only their careers, but also friends, financial security and marriage prospects.

Dr. Martínez-Patiño, now a professor of sports education at the University of Vigo in Spain, advises the IOC alongside Dr. Vilain. She says that the making of regulations that restrict participation of female athletes must be a respectful process that continues to be informed by the science of sex and gender biology.

“The hardest thing is to get people to put themselves in the place of the athletes,” she says. “Behind every athlete there are friends and family, lives and relationships that can be destroyed if the situation is not handled in the best way possible. Those in charge must be aware of the most recent scientific findings in this area, so that the policies they create cause the least possible damage to the women who are affected by these decisions.”

Veronica Meade-Kelly is a science writer at The Broad Institute of MIT and a frequent contributor to Harvard Medicine magazine.



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