The Olympic Games and Debate Over Athletes' Sex

In recent years, 2 female athletes, Caster Semenya and Dutee Chand, attracted intense media attention and will probably also draw attention at Brazil's 2016 Summer Olympics taking place around now. Both unknowingly played important roles in suspending the International Olympic Committee (IOC) and International Association of Athletics Federations (IAAF) “hyperandrogenism” (testosterone) policies. Competitors had concerns about their “masculine” appearance, intensified by intrusive media and social media. We wanted to share an article on this subject from the respected journal JAMA.

Semenya first attracted attention in 2009 by easily winning the 800-meter race at the World Games in Berlin. Rivals' discomfort with her appearance prompted comprehensive medical evaluation of her sex. Returning months later, her appearance was unchanged and she had become an outstanding, highly competitive athlete. This contributed to a blood-testosterone-based hyperandrogenism policy setting an upper female threshold of 10 nmol/L (288 ng(dl), unless the athlete had already been shown insensitive to testosterone.

Testosterone insensitivity, androgen insensitivity or testicular feminization are alternative names for an X-linked recessive genetic syndrome (Androgen Insensitivity Syndrome). Here, despite a male XY genotype, cellular androgen receptor dysfunction produces testosterone resistance and the person is raised as female medically, psychosocially and legally. Semenya's condition has not been disclosed under personal-information privacy principles, but she was allowed to continue competing as a woman. She later won silver at the 2011 World Games and 2012 London Olympics.

Chand, a promising Indian runner, won various national and regional 100-meter races. Similar concerns from rivals led India's athletics federation to investigate. Supported by bioethicists, Chand appealed to the Court of Arbitration for Sport. In July 2015, a detailed 160-page ruling suspended hyperandrogenism policies and found in her favor. Other sports federations were affected too. Hyperandrogenismis excess male sex hormones such as testosterone and is a common endocrine disorder in reproductive-age women, particularly those with polycystic ovary syndromeas an associated condition.

On 25 June 2016, Chand ran 100 meters in 11.32 seconds, becoming the first Indian woman in 36 years to qualify for the Olympics. However, the time seems insufficient to win a medal.

Meanwhile, Semenya had an excellent Olympic preparation year, running the year's best 400- and 800-meter times. She is expected to regain her former performance in Rio, probably with continued media scrutiny and complaints from other athletes. Some will certainly call for revised testosterone thresholds.

During the early Cold War (1945-1966), international sport acted as a proxy for tensions between Eastern and Western blocs. Speculation about Soviet-bloc athletes' femininity encouraged anatomical inspections mockingly called “nude parades”. These allegations led to the introduction at the 1968 Olympic Games of buccal smears to determine genetic sex. Also common in forensic medicine, this collects DNA from inner-cheek cells using a cotton swab. Women are known to have 46-XX chromosomes and men 46-XY. The less harmful but less reliable test sought 2 X chromosomes to identify young women with genetic conditions affecting sexual development, such as androgen insensitivity.

What are now called disorders of sex development would take 20 years to understand better. A workshop organized by the International Amateur Athletic Federation in Monaco in 1990 recommended abandoning laboratory sex testing and conducting doping tests with directly observed urine samples. Participants also proposed allowing individuals born with sex development disorders and raised female to compete as women regardless of chromosomes. Nevertheless, the IOC continued more specific sex-determining gene tests until Australia's 2000 Summer Olympics.

These repeatedly revised policies still permit explicit investigation of potentially ineligible women, as happened after Semenya's sudden emergence in 2009. The resulting media sensation prompted an IOC expert meeting similar to the 1990 Monaco workshop, followed by the arbitration court's suspension of hyperandrogenism policy.

Sports Success Depends on Many Factors

Genetic predisposition is among the most important. From a genetics perspective, height, low body weight and other advantageous traits are controlled by Y-chromosome genes. These factors cause athletes with sex development disorders to face greater scrutiny than others in society with similar conditions.

One performance-enhancing genetic disorder involves mutation in the erythropoietin receptor gene. This increases hemoglobin, the oxygen-carrying component of blood, increasing oxygen capacity and delivery to tissues. Muscles tire later, providing extra endurance. Congenital conditions increasing testosterone have similar effects. Increasing numbers of transgender athletes, whose gender identity differs from assigned sex, make distinguishing biological differences from performance-enhancing substance use harder. However, this is uncommon compared with performance-enhancing substance use.

The performance difference between sexes in sport is 10 to 12 percent, so many Olympic events separate competitors by sex. However, media scrutiny of female athletes from less developed countries without distinguishing their biology has shown the hyperandrogenism policy's limited validity for identifying sex differences. Everyone in sport should therefore be informed about factors contributing to success. An article published in earlier years proposed that athletes born with sex development disorders and raised as girls should compete in the women's category.