Open Extended ReactionsMONACO -- Clarifying promised rules on female eligibility, track and field's governing body set a Sept. 1 deadline Wednesday for athletes to pass a gene test for competing at the world championships. World Athletics said in March that it would require chromosome testing by cheek swabs or dry blood-spot tests for female athletes to be eligible for elite-level events. "We are saying, at elite level, for you to compete in the female category, you have to be biologically female," World Athletics president Sebastian Coe said. "The SRY [sex-determining Region Y gene] test is extremely accurate and the risk of false negative or positive is extremely unlikely," World Athletics said. "The transitional provisions do not apply to transgender women as there are none competing at the elite international level under the current regulations," World Athletics said.