CLINICAL MATTERS

The terrible bullying that Olympic boxer Imane Khelif endured due to misconceptions about her sex during the Olympics is a clear indication that our understanding of human sexuality is imperfect and continues to evolve. To begin with, many people continue to use gender and sex interchangeably when these terms do not mean the same thing. As a physician who takes care of a lot of people with diverse sexual identities, I have had to understand many nuances in language in order to be as inclusive as possible in my practice. This also means striving to be constantly updated about the latest developments in this field and applying it to my patients.

Biological sex refers to specific attributes in different organisms that have distinct male and female forms. Genotypic sex refers to the presence of a specific genetic pattern that differentiates a male and a female. This pattern may be different for plants and animals. In the case of humans, our genome is made up of 46 chromosomes, including two X chromosomes for females and one X plus one Y chromosome for males. 

The presence of a Y chromosome denotes genotypic male sex since it contains the SRY gene which produces the male phenotype. Phenotypic sex is an expression of the genes into male versus female parts and structures. This is the basis that doctors use to assign a person’s sex at birth. A 46XX genotype typically produces a female phenotype with a specific body type which includes breasts, wide hips, ovaries, Fallopian tubes, a uterus, a vagina, and external female genitalia. A 46XY genotype typically produces a male phenotype including a penis, testicles, a scrotum, and a male physique. 

In the past, genotypic sex was proposed to be the final determining factor for sex. In other words, if you have a Y chromosome, it used to be dogma that you were biologically male.
The recognition of a group of diseases known as differences in sex development (DSDs), however, has shown that even XY individuals can have female phenotypes due to certain mutations in the sex chromosomes, atypical secretion of hormones from the sex glands (the testes and ovaries), or atypical responses of tissues to sex hormones during development. The default phenotypic sex of a human embryo is female, and it is the secretion of male hormones such as testosterone that induce the development of the male phenotype. If the secretion of male hormones fails whether from a genetic mutation, failed development of the sex glands, or a failure of the target tissues to respond, the fetus will be phenotypically female. If there is a partial response, the baby may be born with ambiguous genitalia and further testing may be needed prior to assigning a sex to the child.   

The main issue for sports in deciding whether someone can participate in the male or female division lies in the advantages in physiology that each sex may have over the other in specific sports. 

For instance, in strength-based contests, males who typically have more muscle mass may have an undue advantage over females. 

A phenotypic female with XY (male genotype) chromosomes, however, who has a condition where there has never been enough testosterone for her to develop male sexual genitalia or a male physique may not have any advantage over a genotypic (XX) female. It is because of this ambiguity and the desire to be inclusive that the rules have been adapted to be sensitive to these distinctions. This process of inclusion remains an imperfect science and so there are bound to be differences in opinion. 

The bottom line is that an XY genotype no longer automatically means that someone is male, especially if they are phenotypically female. After all, there may be a lot of persons with XY genotypes who are phenotypically female but do not get tested because they conform to what is the expected body type, while women who are genotypically female but who look “masculine” may be unfairly targeted and forced to undergo testing. Balancing the need for fair play over the potential for discrimination in testing is an ethical tightrope that needs to be constantly recalibrated, depending on the latest findings and medical consensus.

Gender, on the other hand, is a choice. This refers to roles and behaviors that an individual chooses in terms of social identity. It is not static and can change over time. Beyond the binary genders of man or woman are other identities and preferences in sexual and social interactions. Lesbian, gay, bisexual, transexual, intersex, non-binary, and queer are just a few of the diverse genders that are recognized. The terms cisgender and transgender refer to an interplay between phenotypic sex (the sex assigned at birth by the doctor) with a person’s sexual identity. A phenotypic male who identifies as a man is a cisgender male, while a phenotypic male who identifies as a woman is a transgender woman. Sexual preferences like being homosexual or heterosexual are also affected by cisgender or transgender identification. For instance, a transgender woman who is phenotypically male who has sex with a cisgender male would be considered heterosexual and not gay; while a cisgender male who has sex with transgender man would be a homosexual. 

Gender can be fluid, and some prefer not to be classified to any kind of category at all. In terms of sports participation, gender generally has no bearing on eligibility.  There may be some exceptions however depending on the relevant sports governing body. A transman (short for transgendered man) who is assigned female sex at birth can compete as a female in most instances as long as the other eligibility criteria are met and no banned substances are used. 
A transwoman however would generally not be allowed to compete in female sports in the Olympics. Certain DSD conditions can result in elevated testosterone levels or other sex hormones beyond agreed-upon cutoffs and these may cause someone to become ineligible depending on what rules have been adopted. These cases are reviewed on an individual basis. This would only naturally apply to certain sports, like strength-based activities. It would be less relevant for non-physical sports like chess where body types would not matter and they can decide on their own rules.

In the case of Imane Khelif, the issue is further muddled by a dispute between the International Olympic Committee (IOC) and the International Boxing Association (IBA). The IBA, which has been barred from the Olympics, banned Imane and another boxer (Taiwanese boxer Lin Yu-Ting) in a seemingly arbitrary fashion in an international meet even when they were allowed to participate in previous events. Leaked letters of uncertain provenance alleged that the two boxers had XY genotypes. 

The IOC rejected these allegations and maintains that it cleared both athletes in accordance with its own rules and refused to comment on the testing due to privacy issues. If, for arguments sake, we do accept the finding that the two boxers do have XY genotypes, this should not mean that they are automatically disqualified. In the first place, both athletes identify as women and were assigned female sex at birth. If they do have DSD, as long as hormonal levels do not exceed the set standards and they have nonfunctional male gonads, then it is reasonable to allow them to compete. On the other hand, an athlete who is assigned male sex at birth and identifies as a transwoman would likely not be allowed to compete in female sports as they would have an undue physiological advantage even if they are taking hormones to suppress testosterone since much of the male physiology would already have developed by then. This is clearly not the case with these two athletes.

It is important to constantly review standards in the interest of fair play, especially at high level competitive sports. This should be done in a humane and sensitive manner, guided by as much objective scientific data as possible. The current controversy shows that we still have much to learn about sex and gender. Ignorant, hasty, and uninformed pronouncements which are prevalent in social media are a sad reality when people let their emotions dictate their actions. We should all strive to do better by deepening our understanding of the evolving paradigms and mysteries of human sexuality, and always respect one another as fellow citizens of the world.