“In plain English, the federal government is proposing reclassifying transgender people’s legal sex back to the sex assigned at birth. And if that sex at birth was listed wrong or left unclear, the government wants to put people through genetic testing to ensure a sort of “gender purity,” as it were.
The problem is, according to experts in the field of genetics, sex development, sex verification testing, and intersex advocacy, genetic testing is far from the “reliable evidence” described in the memo. In fact, it often cannot accurately tell us a person’s sex, much less their gender identity. And the HHS memo appears to conflate the concepts of biological sex and gender identity as if they were the exact same thing — which all major medical and psychological associations now agree is not the case.
Jessica Lynch Alfaro, an associate professor and Vice Chair for Undergraduate Education at the UCLA Institute for Society and Genetics, said the methodology described in the HHS memo “doesn’t make sense scientifically.”
Alfaro said the memo contains two major inaccuracies that clash with today’s scientific understanding of sex development. The first thing she highlighted is the use of the phrase “immutable biological traits” in the memo. “Biological traits are not immutable. First they’re saying genitalia at birth, but genitalia, as we know, is changeable,” Alfaro said.
“In terms of the genetics, the developmental process of sex determination and differentiation in humans is complex,” Alfaro said. Several factors contribute to what we call the “sex” of a person, she explained, including chromosomes, hormones, gonads (internal sex organs like ovaries and testes), external genitalia, and secondary sex characteristics that appear later in life.
In school, we’re taught that men have XY chromosomes and women have XX chromosomes — but that’s not exactly the case. For example, Alfaro said, some men have XXY chromosomes. And some women have XY chromosomes, but develop ovaries and other characteristics that typically fit the female phenotype because they lack the SRY gene responsible for shifting the development of ovaries to testes.”