IOC SRY – The International Olympic Committee has adopted a new requirement for gene testing of female athletes based on the SRY gene ahead of the 2028 Olympics. Critics say it closely mirrors a 1999 policy the IOC dropped after concerns about inaccuracies, costs, and p
For athletes, the fear isn’t theoretical. Years after the IOC abandoned sex verification tests, the memory of what the process felt like still sits in the body.
Now. with the International Olympic Committee announcing a return to genetic testing for women athletes—this time under a new requirement tied to the SRY gene—the debate is stirring again. not just about fairness. but about privacy. accuracy. and the psychological weight of being told a stranger can define your sex.
The IOC’s “Working Group on the Protection of the Female Category. ” which announced the policy in March. adopted the plan that will require gene testing for female athletes beginning with the 2028 Summer Olympics. The IOC says the genetic testing policy “protects fairness. safety and integrity in the female category. ” and it is intended to ban “biological males. ” including transgender women. from competing in Olympic events for females over concerns of potential competitive advantages.
To date, New Zealand weightlifter Laurel Hubbard has been the only openly transgender woman to compete in the Olympics.
But critics say the IOC is repeating a failure. They point to a policy discontinued in 1999—almost identical in purpose—over concerns about inaccuracies, costs, and the psychological trauma it caused.
“What they decided to do was what they did 30 years ago. All the advances and so forth in women and athletes that we worked on for 30 years or something like this. have been reversed. ” said Myron Genel. professor emeritus of pediatric endocrinology at Yale University and one of the medical professionals who pushed the IOC to drop its previous sex testing policy.
The IOC declined multiple requests from a U.S. newsroom outlet to elaborate on the science behind the policy or to identify the medical experts and stakeholders consulted. When asked for details about the program’s costs. how it will be implemented. and potential legal hurdles. the IOC directed readers to an FAQ that critics say does not address their concerns. The FAQ places responsibility for execution on international sport federations and athletes.
The IOC says the SRY gene is “highly accurate evidence of sex.” But that claim clashes with the recommendation of the person who discovered the gene.
“The SRY gene alone should not determine who can compete in women’s sport,” Andrew Sinclair, deputy director of the Murdoch Children’s Research Institute in Australia, said in a statement provided to a U.S. newsroom outlet.
The sharpest difference between the IOC’s new plan and its abandoned predecessor is where the testing happens. Critics say that shift is likely to make the process more chaotic.
The IOC will not be administering the required gene test the way it did in the 1990s. Instead, it will make testing the responsibility of international sport federations and sports governing bodies. The IOC says it will conduct educational seminars for those federations and governing bodies, beginning “in the coming weeks.”.
Reo Eveleth, creator of “Tested,” a six-part audio documentary on the history of sex testing in elite sports released in 2024 with NPR and the CBC, said the result will be messy.
“It’s going to end up being an incredibly complicated and messy process, in which people not qualified to do so (are going to run testing),” Eveleth said.
“It’s going to be a nightmare for people,” Eveleth added. “I don’t know how you navigate it ethically, because I don’t know that it’s possible to do so.”
Before the SRY tests, the Olympics tried other methods.
Going as far back as the 1930s. the IOC employed different tactics to guard against the possibility that men were surreptitiously competing in women’s events. The IOC first subjected female athletes to physical examinations. including “nude parades. ” in which women had to strip down and walk in front of doctors to show their female genitalia.
In the late 1960s, the IOC switched to chromosome tests. The first, the Barr Body test, confirmed women athletes had XX chromosomes. After the 1990 discovery of the SRY gene—which is found on the Y chromosome and is key for typical male sex development—the IOC began testing for that.
Those gene tests. though they may sound like a harmless cheek swab. became a source of anxiety for many women athletes. The tests were often inaccurate, producing positive results for women with differences in sex development (DSD). Intersex women, for example, or women with chromosomal abnormalities.
There was fear of being told you are not the person you’ve always thought you were and the humiliation that would cause. There was also alarm at the possibility that athletic careers could end instantly, after years of training and sacrifice.
Eveleth described one woman so petrified that she paid to take the test on her own first to be certain she’d pass the IOC test.
“It’s a fundamentally terrible thing to have a stranger tell you, ‘I have tested your body and I’m telling you that you don’t know yourself. You’re actually a man.’ I don’t know how you process that,” Eveleth said.
“And then on top of that, your (athletic) dreams are over.”
The fears weren’t unwarranted. At the Atlanta Olympics in 1996, eight of 3,387 female athletes tested positive for the SRY gene. After further examination, all were allowed to compete.
By then, medical groups had publicly opposed gene testing for sex verification. The American Academy of Pediatrics. American College of Obstetricians and Gynecologists. American College of Physicians. and American Medical Association had all taken that position. The American College of Physicians still does.
Individual experts also urged the IOC to drop the testing. Even the IOC’s own Athletes Commission came out against it. Speedskater Johann Olav Koss wrote a detailed presentation on why gene testing should be stopped. Koss, a four-time Olympic champion with a medical degree, said the test was simply wrong.
“It was obviously the wrong test. Gender … is so much more than chromosomes and it made no sense to keep testing,” Koss said.
In 1999, the IOC dropped its sex verification for female athletes.
“I thought it was one of my biggest achievements, to be honest,” Koss said. “At the time, of course, because I thought it was ridiculous to do that test. But I do still think it’s ridiculous.”
The IOC’s old policy was designed to weed out men secretly trying to compete as women. The new rule is designed to keep transgender women out of women’s sports.
But critics say the problems that led to the 1999 drop still remain.
Most women with differences in sex development will be barred from competition under the IOC’s new rule. even as critics argue there is still no evidence they have a competitive advantage. The IOC says exceptions could be made for athletes who test positive for the SRY gene but are diagnosed with Complete Androgen Insensitivity Syndrome (CAIS) or “another rare condition that precludes typical male sex development. ” but it has not provided details on how those exceptions would be determined.
Chris Mosier, a runner and advocate who became the first known transgender man to represent the U.S. in international competition in 2015, said he is disappointed in the IOC decision to backtrack on inclusion.
Mosier criticized the IOC for not releasing the names of the people involved in creating its new policy, which goes into effect for the 2028 Los Angeles Olympics.
IOC president Kirsty Coventry has said the new policy is based in science, but she has repeatedly declined to make that science public. The IOC has also not identified the medical experts on the panel that made the recommendation to resume sex verification.
“They’re dressing it up in a lot of allegedly scientific arguments. Coventry says the science is clear, when that’s not true,” Eveleth said. “There’s this extensive manufacturing of evidence to make it seem there is all this reason for it when it doesn’t hold up.”
Sinclair, the geneticist who discovered the SRY gene, said the SRY gene alone is not enough to decide who qualifies as male.
“Male sex is much more complex, involving multiple genes other than SRY in developmental pathways as well as hormones,” Sinclair said.
“The presence or absence of the SRY gene does not determine the range of human sex characteristics. Individuals with differences of sex development may carry the SRY gene but develop either complete or partial female bodies while others develop male bodies but lack SRY. ” Sinclair added. “All the SRY test tells you is whether or not the gene is present. It does not tell you how SRY is functioning. whether a testis has formed. whether testosterone is produced and. if so. whether it can be used by the body.”.
Reo Eveleth also pointed to the consequences of shifting testing out of the IOC’s control. The IOC’s previous gene testing efforts were done by its own people or by the Olympic hosts. Under the new policy, the testing will be done by individual sport federations and governing bodies.
The IOC also glossed over the fact that some countries—including France and Norway—bar genetic testing for this purpose, meaning athletes can test elsewhere.
The IOC acknowledged the trauma testing might inflict, especially on younger athletes, and said counseling would be available. But it puts the responsibility—and cost—on international federations and sports governing bodies.
“You know there is, by your own admission, foreseeable harm here. You argue it is worth it to solve this problem that isn’t real. I don’t know how you justify that,” Eveleth said.
In its announcement, the IOC states: “Athletes with an SRY-positive screen, including XY transgender and androgen-sensitive XY-DSD (differences in sex development) athletes, continue to be included in all other classifications for which they qualify.”
Critics argue that the uncertainty around how the policy will be implemented and which athletes will be excluded means the underlying problem is unchanged.
“It doesn’t feel like anything has really changed – about the test, the implementation, about the problem that doesn’t really exist. Yet we’re doing it again for some reason,” Eveleth said.
“It’s this really demented game of whack-a-mole.”
For Spanish hurdler Maria Jose Martinez Patino, the debate is not abstract.
Patino was banned in 1985 after a test found she had XY chromosomes. Her results became public, and in a 2025 speech she said the press in her country decided it would be a headline and announced that Spain’s best hurdler had chromosomes that do not belong to her.
She said she endured public humiliation and the loss of her athletic career.
Patino challenged the ban and was eventually reinstated after proving she was an intersex woman and that androgen insensitivity syndrome did not give her a competitive advantage. She came up just short of qualifying for the 1992 Olympics.
In her 2025 speech, Patino criticized who gets to speak about medical issues in sports.
“Bit by bit, we have let everyone to have an opinion on medical matters, when the only people who can help or have the right to speak openly and state the facts as they are, should be medical specialists. Not politicians, not journalists, and least of all sports officials,” she said.
By the late 1980s, officials had already begun reconsidering sex verification. The International Amateur Athletic Association, which had led the push for gene testing then, convened panels of medical experts. In 1992. it declared that women with differences in sex development did not have a competitive advantage and dropped its gene testing requirement.
The IOC persisted, and so did the problems.
The cycle ended in 1999 when the IOC dropped its sex verification for female athletes—after objections from medical groups, athletes, and medical professionals including Koss and Genel.
Now the IOC says its new gene-testing policy begins a new phase designed to protect fairness. safety and integrity in the female category. Critics say it doesn’t undo what was wrong before; it simply places a fresh set of athletes back in the same spotlight—this time under a different label. and with responsibility shifted beyond the IOC itself.
International Olympic Committee IOC gene testing SRY gene female athletes 2028 Summer Olympics Laurel Hubbard Kirsty Coventry Chris Mosier Andrew Sinclair Myron Genel Reo Eveleth Johann Olav Koss sex verification transgender women sports policy