Are we genetically literate enough for gender verification in Sport?

Ambroise Wonkam, Senior Lecturer / Senior Specialist,
September 14, 2010
Dear Editor

In the midst of the genetic/genomic medicine revolution, the Caster's controversy illustrates how human society is lacking in its ability to deal with Disorders of Sex Development (DSD) at either a social, competitive, legal or ethical level. Political fractionalization, by way of "protecting human rights" added fuel to the fire rather than defusing the situation. "We can't afford any mistakes, particularly as we already face threats to be taken to the United Nations Human Rights Council and because it has become a political matter in South Africa," said The International Association of Athletics Federations (IAAF) spokesman Nick Davies.1 Controversial issue in gender verification in sport include failure to understand the complexities of DSD, screening tests lacking validity, the discriminatory singling out of women based only on laboratory results and the stigmatization and emotional trauma experienced by individuals screened positive.2 The debate spurred by Caster's demands reflection on the meaning and aims of sport, its ethics and philosophy.3

Foddy and Savulescu are absolutely on target when they note that any attempt to use genetic or functional biochemical information for gender identification purposes would be inappropriate.4 As the authors reviewed, the historical physical inspection could not determine gender in some conditions; e.g. 46, XY pure gonadal dysgenesis 'where the apparent female' might have complete female external genitalia, but genetically, 'she' has an X and a Y chromosome, effectively being classified 'male'. On buccal smears, it was decided that XX athletes (with two X chromatids) were female. In fact, a female athlete with Turner syndrome (45, XO) would "fail" the gender test. Paradoxically, the test would have permitted men with Klinefelter's syndrome (47, XXY) to compete. It was also difficult to use the DNA detection of SRY gene (sex determining region of the Y chromosome). An athlete with 46, XX true hermaphroditism, may have an advantage in sport from her higher level of testosterone in the presence of testicular tissue and negative SRY test.

DSD could be classified into three groups: 1) sex chromosome abnormalities (including abnormal numbers and abnormal structures), 2) gonadal abnormalities and 3) sex hormone abnormalities (including abnormal levels of androgen and receptor defects).5 In addition, some authors recently claimed that defining functional advantage, irrespective of the genetic sex, could be useful for gender verification in ensuring fairer Olympics.6 The 46, XX females with congenital adrenal hyperplasia (CAH), have a much higher level of testosterone that might be an advantage in sport. One could argue that such individuals should not compete in the female category because of possible advantages in sport. But which sport? Women with CAH are expected to be shorter than average7 and would not be able to use this "advantage" in basketball! Salt loss that can occur in the condition may lead to a degree of fatigability, a potential disadvantage. In addition, treatment with glucocorticoids that is directed at preventing adrenal crises and ensuring normal childhood growth by alleviating hyperandrogenism7 could trigger an enhancement issue. Moreover, a greater understanding of the genotype-phenotype correlation supports the view that 21-OH Deficiency is a continuum of phenotypes,8,9 with variable expression of CAH even within a family.10 Another case in point is the condition called androgen insensitivity syndrome. The phenotype in partial form is extremely variable and is rarely predicted by the androgen receptor genotype;11,12 it is fair to classify an athlete with this condition to compete in a male category? Probably not! There just isn't a simple answer! Foddy and Savulescu amply illustrate that functional classification will be inadequate, in as much as, numerous genetic factors explain the extremely high variation in serum testosterone between individuals and no routine functional test is available to measure the effect of hormones androgen receptors.4

It should be added that any genetic testing should be accompanied by adequate counseling, informed consent, and respect for confidentiality13. Before the competition in Berlin, an email exchange between Harold Adams, the team doctor, and Molatelo Malehopo, the Athletic South Africa (ASA) general manager, discussed and authorized gender testing, with South African athletics chief Leonard Chuene copied in. Semenya was tested before competing in Berlin. Chuene later admitted that he was aware of this, but had kept the information confidential to protect Semenya's privacy. Interestingly, Wilfred Daniels, the team coach, also confirmed Semenya was made to undergo tests without being fully aware of their nature, and that tests were undertaken on August 7, 2009.14 In Berlin, the IAAF reported that two things triggered the investigation: firstly, the 'incredible improvement in the athlete's performance and secondly the fact that a South African blog was alleging that she was a hermaphrodite athlete"15 It's clear that none of routinely accepted genetic test and genetic counseling principles were respected from the beginning. First, how could we explain that medical professionals in South Africa carried out such an important gender test not only without any prior genetic counseling for the patient, but more gravely, without informing the client of the nature of the tests? Where are the principles of full information, informed consent, autonomy and non-directiveness? Where are the principles of confidentiality when the entire ASA team of officials including the coach (all but Caster) was aware of the nature of the first gender test? Secondly, in Berlin, the IAAF stood its ground, saying it only made the gender test public after it had already been reported in the media. Where was the professionalism of their medical expert committee with a duty to care about the dignity, emotional distress and confidentially rights of Caster? Thirdly, if political officials were properly informed about the complexity of genetic issues, especially gender disorders, would the public have faced such ill informed passionate public pronouncements? Finally, was the media right to give so much attention to this gender testing issue?13

The number of genetic 'abnormalities' concerning gender together with variable expression, and their complexity infers that the current IAAF gender policy is inadequate to cope with such cases. Gender verification has potential or causing great psychological harm to women who may unknowingly have a DSD and is far more likely to bar unfairly from competition women with genetic abnormalities that confer no such advantage that safeguard fair competition. The results of the gender verification tests on Caster were awaited by the end of November 2009, but IAAF has decided not to disclose those results. Interestingly, Semenya returned to competition in July 2010 after receiving confirmation from the IAAF that she could compete as a woman.16


1. Anonymous. IAAF tell ASA to test Semenya (2009). Retrieved March 15, 2010 from

2. Reeser JC. Gender identity and sport: is the playing field level? Br J Sports Med 2005; 39: 695-9.

3. Camporesi S, Maugeri P. Caster Semenya: sport, categories and the creative role of ethics. J Med Ethics. 2010 Jun;36(6):378-9.

4. Foddy B, Savulescu J.Time to re-evaluate gender segregation in athletics? Br J Sports Med. 2010. DOI: 10.1136/bjsm.2010.071639.

5. Lee PA, Houk CP, Ahmed SF, Hughes IA. and in collaboration with the participants in the International consensus conference on intersex organized by the Lawson Wilkins pediatric endocrine society and the European society for paediatric endocrinology. Consensus statement on management of intersex disorders. Pediatrics 2006; 118: e488-e500.

6. Tian Q, He F, Zhou Y, Ge Q. Gender verification in athletes with disorders of sex development. Gynecol Endocrinol 2009; 25: 117-121

7. Tahirovic H, Toromanovic A, Grubic M, et al. Untreated congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Eur J Pediatr 2009; 168: 847-9

8. Huynh T, McGown I, Cowley D, et al. The clinical and biochemical spectrum of congenital adrenal hyperplasia secondary to 21-hydroxylase deficiency. Clin Biochem Rev 2009; 30: 75-86.

9. Goossens K, Juniarto AZ, Timmerman MA, et al. Lack of correlation between phenotype and genotype in untreated 21-hydroxylase-deficient Indonesian patients. Clin Endocrinol (Oxf) 2009; 71: 628-35.

10. Tardy V, Menassa R, Sulmont V et al. Phenotype-genotype correlations of 13 rare CYP21A2 mutations detected in 46 patients affected with 21-hydroxylase deficiency and in one carrier. J Clin Endocrinol Metab 2010; 95:1288-300.

11. Boehmer AL, Brinkmann O, Br?ggenwirth H, et al. Genotype versus phenotype in families with androgen insensitivity syndrome. J Clin Endocrinol Metab 2001; 86: 4151-60.

12. Deeb A, Mason C, Lee YS, Hughes IA . Correlation between genotype, phenotype and sex of rearing in 111 patients with partial androgen insensitivity syndrome. Clin Endocrinol (Oxf) 2005; 63: 56-6.

13. Wonkam A, Fieggen K, Ramesar R. Beyond the Caster Semenya Controversy: The Case of the Use of Genetics for Gender Testing in Sport. J Genet Couns. 2010. DOI : 10.1007/s10897-010-9320-2

14. Samuel M. Sorry Tale, probed south African Athlete Caster Semenya (2009). Retrieved March 15, 2010 from: . 15. Wilson N. Athletics: boy, That's some win! Golden girl Caster Semenya to face sex test (2009). Retrieved March

15, 2010 from:

16. CLAREY C As Semenya Returns, So Do Questions (2010) retrieved 13 September 2010 from

Conflict of Interest:

None declared

Conflict of Interest

None declared