You may have heard of the controversy involving two boxers competing in the female division of the sport in the Paris Olympics. The issue causing the furor is whether the competitors are really female. The press reports state that previous testing has shown that the two have XY chromosomes and high levels of testosterone. They were raised as females and vigorously state that they are such.
The following is speculation on my part and is solely based on what has been reported by the press. Thus, it may be off the mark. There is a medical condition that could explain all the features said to be present in these two athletes. There is a genetic condition, 5-alpha reductase deficiency, that could be present in the two boxers. It is a rare hereditary disorder caused by the mutation of the SRD5A2 gene. It is an autosomal recessive mutation that requires the altered gene be present in both parents and a copy of the gene be transmitted to the embryo by both parents. Autosomal means it’s not on a sex chromosome.
The enzyme in question catalyzes the conversion of testosterone to dihydrotestosterone. It is the latter hormone that is responsible for the fetal emergence of male genitalia. In its total absence, the resultant genitalia will be female.
Some babies with the disorder will appear female at birth and be raised as females even though they are genetically male. At puberty when testosterone surges the genitalia will change and become more like the male form. Some children at this time will choose to change their gender identification from female to male. Others, however, will wish to remain female.
The subject with this disorder will not have facial hair, temporal recession, male pattern baldness, or the increased body hair typical of adult males as these features are mediated by dihydrotestosterone. They will however develop the increased muscle and skeletal mass that differentiates adult males from females. They are typically infertile. For a good discussion of this syndrome go here.
This disorder could explain all the features of these two athletes mentioned above – lifelong female identification, XY chromosomes, and high blood testosterone levels. The Olympic committee has mishandled the controversy by saying that their competitors’ gender is that which appears on their passports. Hardly, a dispositive solution. If these two athletes have the genetic mutation described above they should not be competing against female athletes irrespective of their lifelong identification as females as their muscle mass and strength is inappropriate for competing with female athletes, much less in a potentially lethal sport. I feel great compassion for their plight as, if my scenario is correct, they have done nothing wrong.
The Olympic administrators need some medical consultants who go beyond sports medicine and orthopedic surgery. An endocrinologist or geneticist might be useful here.
