"According to a recent report in the New York Times, the Department of Health and Human Services is 'considering narrowly defining gender as a biological, immutable condition determined by genitalia at birth.' While the department's memo purports to be 'grounded in science,' the arguments and conclusions are not. Specifically, the memo argues that sex should be determined by--at different points in the purported memo--birth certificates, genitals and genetics. The problem with this argument is that none of these markers of sex is 'definitive proof of a person's sex' and in fact, nothing is. In reality, the course of becoming a 'male' or 'female' involves several steps, regulated by many genes and hormones.
"Much of the time these processes all go in the same direction. But some of the time, they don't. Seeing how that happens makes clear that the proposal, to define all people as male or female at birth, is scientifically dubious."
-- Kristina R. Olson and Sheri Berenbaum, Scientific American's "Voices" blog, 2018-10-29
[If you vote for Republicans, you are not voting for people who don't care about me; you are voting for people who want to harm me. I really hope that your sense of "people you personally know and like" matters more than your sense of "political tribe".]