In advance of the 2025 World Athletics Championships in Tokyo, World Athletics (WA) announced that passing a genetic test, specifically for the absence of the SRY gene, is a prerequisite for competing in the women’s category in all athletics World Rankings Competitions as of 1 September 2025 (). Athletes who do not pass the test will be considered ‘biological males’ and required to prove that they have complete androgen insensitivity syndrome (CAIS) in order to compete. This requirement recycles an intentionally discontinued practice from the last century. After ending the discredited chromosome (Barr body) tests that had been used since the 1960s, the International Olympic Committee briefly used SRY gene tests from 1992 to 19991 before they were also withdrawn because of inaccuracy, lack of evidence of performance advantage, excessive cost including the cost of counselling, and the trauma and stigmatisation experienced by athletes and their families.

The initial…