A San Jose State University biology professor recently accused a Texas state legislator of being “bigoted” for tweeting that there are only two genders.

“In case you forgot how many genders there are,” Republican State Representative Briscoe Cain tweeted on December 21, attaching a picture of the XX and XY chromosomes.

"One thing I am not doing is arguing with someone whose basic premise is incorrect and tries to tell me that they know more about my science, in which I am an expert, than I do."

[RELATED: UCLA students threatened online for saying ‘there are only two genders’]

Describing herself as a geneticist, Rachael French replied to the tweet with an extended harangue in which she impugned Cain’s motives and derided his understanding of biology.

“Hey geneticist here. You’ve disingenuously and for bigoted purposes oversimplified a complex phenomenon,” she wrote. “A few notes: 1) Sex and gender aren’t the same thing. 2) Chromosomes don’t determine sex.”

“I know high school biology told you they do, but nope,” she continued in a separate tweet. “A single gene on the Y starts a cascade of events involving genes all over the genome to determine sex. If any of those things changes, surprise!”

French went on to differentiate between gender, which she describes as “a complex phenomenon arising from interactions between genes and the environment,” and sex, which “describes the physical manifestations” of that interaction.

“‘Gender’ describes the psychological and/or the emotional identity,” she elaborated, saying, “they’re regulated somewhat, though certainly not entirely, independently.”

[RELATED: Harvard tells students gender can ‘change from day to day’]

“Finally, there are more than two sexes at the somatic level,” she concluded, pointing out that some individuals exhibit physical traits that are inconsistent with their chromosomal sex.

“Intersex and ambiguously sexed individuals arise at an appreciable frequency - on the order of 1%,” she asserted. “This is because physical sex is more hormonal, not chromosomal.”

One user questioned French’s arguments, countering that saying “‘Sex and gender aren’t the same thing,’ isn’t at all a genetic statement. It’s a questionable sociological construct.”

French, however, refused to engage in that debate, citing her academic credentials as a means of dismissing the comment out of hand.

“One thing I am not doing is arguing with someone whose basic premise is incorrect and tries to tell me that they know more about my science, in which I am an expert, than I do,” she wrote.

In a separate tweet on December 24, French added that she teaches “this sex determination stuff” to roughly 200 people every year, and “the gender identity bit” to approximately 40, expressing satisfaction that her response to Cain’s tweet reached “at least five times as many in 24 hours.”

Cain has since made his Twitter account private, but told Campus Reform that the decision was unrelated to the exchange.

Campus Reform reached out to French for comment, but has not received a response.

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