The Trump administration has reportedly moved to establish a legal definition of gender as a biological condition determined by genitalia at birth, a move that would essentially undo the protection and recognition of transgender people granted by federal civil rights law. Citing a memo reportedly sent out by the Department of Health and Human Services, The New York Times reports that the agency is pushing for key government agencies to adopt a definition of gender as something determined “on a biological basis that is clear, grounded in science, objective and administrable.” The definition suggested by the agency would rigidly define sex as unchangeable, either male or female, and determined by genitalia at the time of birth, according to the Times. “The sex listed on a person’s birth certificate, as originally issued, shall constitute definitive proof of a person’s sex unless rebutted by reliable genetic evidence,” the memo reportedly reads. Trump administration officials say the proposed definition is expected to be presented to the Justice Department by the end of the year. If deemed legal, an estimated 1.4 million Americans identifying as a gender other than the one with which they were born may lose federal recognition.