Experiment

If you remember the case of David Reimer you will note how it taught us about how a gender identity cannot be imposed. John Money insisted to his parents that the botched circumcision need not be a problem and they could simply raise him as a girl which they did.

Brenda (as he was known then) turned out to be a tomboy who refused to wear dresses and wanted to rough house with the boys. When he was told the truth, he began to live as a male and eventually married a woman only to ultimately commit suicide in his thirties.

So if this case shows us that at least part of gender is rooted in biology, it lends credence to the argument that it can be altered simply because all biological processes produce anomalies. What we currently term gender dysphoria is likely the product of biology possibly combined with sociological aspects thrown in for good measure. All this counteracting the argument by transphobes that transgender people are created via social contagion rather than through root causes (here I am purposefully leaving out elective gender variance which of course exists).

John Money's tragic experiment proved something but unfortunately it was at the cost of a precious life.