Sex v. Gender

Most people think that they are one and the same but most trans people know they are not; one is between your legs and the other is in your brain.

Sex redefined
The idea of two sexes is simplistic. Biologists now think there is a wider spectrum than that.
Nature
Claire Ainsworth
18 February 2015

Sex can be much more complicated than it at first seems. According to the simple scenario, the presence or absence of a Y chromosome is what counts: with it, you are male, and without it, you are female. But doctors have long known that some people straddle the boundary — their sex chromosomes say one thing, but their gonads (ovaries or testes) or sexual anatomy say another. Parents of children with these kinds of conditions — known as intersex conditions, or differences or disorders of sex development (DSDs) — often face difficult decisions about whether to bring up their child as a boy or a girl. Some researchers now say that as many as 1 person in 100 has some form of DSD.
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These discoveries do not sit well in a world in which sex is still defined in binary terms. Few legal systems allow for any ambiguity in biological sex, and a person's legal rights and social status can be heavily influenced by whether their birth certificate says male or female.

There are many who think that gender dysphoria has its roots biology, that forever what reason or reasons our brains do not develop as a typical male or female brains. For whatever reasons we know our true gender was not the gender that was assigned to us at birth.

It is interesting to note that the same is true for intersex people who were assigned a gender at birth contrary to their true gender.

Yet if biologists continue to show that sex is a spectrum, then society and state will have to grapple with the consequences, and work out where and how to draw the line. Many transgender and intersex activists dream of a world where a person's sex or gender is irrelevant. Although some governments are moving in this direction, Greenberg is pessimistic about the prospects of realizing this dream — in the United States, at least. “I think to get rid of gender markers altogether or to allow a third, indeterminate marker, is going to be difficult.”

So if the law requires that a person is male or female, should that sex be assigned by anatomy, hormones, cells or chromosomes, and what should be done if they clash? “My feeling is that since there is not one biological parameter that takes over every other parameter, at the end of the day, gender identity seems to be the most reasonable parameter,” says Vilain. In other words, if you want to know whether someone is male or female, it may be best just to ask.

Maybe the next best option is to leave the gender blank on the birth certificate until the child is old enough to say what their true gender.