But recently scientists have begun to look more closely into the neurology, physiology, and psychology behind it.

しかし、最近、神経学、生理学、心理学…その背景にあるものを科学者達はより詳細な調査を始めました。

So today, we're gonna break down what science does know in a respectful and educational way.

今日は科学で敬意を持って、教育的に、解明されていることを整理してみましょう。

Hey guys! I'm Gigi Gorgeous.

やあ、みなさん！私はジジ・ゴージャスです。

And today, I'm here with ASAPScience to break down 'The Science of Being Transgender'..

今日は「トランスジェンダーであることの科学」を分析するために、ASAPScienceにお邪魔しています。

Before we get too deep into it, we have to look at your genetic sex, or the chromosomes you have.

深く掘り下げる前に、あなたの遺伝的性、もしくはあなたが持っている染色体を見なければなりません

These were determined right at fertilization, when the sperm cell from your father, which carries an X or a Y chromosome fused with the egg from your mother, which carries an X chromosome.

これらはまさに受精の瞬間に決定しました。父親からの精子細胞がXかYの染色体を持っていて、X染色体を持つ母親の卵子と融合した時です。

But until 6 or 7 weeks after fertilization, both XY and XX embryos have identical gonads.

しかし、受精後6～7週間後まではXY胚もXX胚も、同一の生殖腺を持っています。

Around 7 weeks, the male sex organs start to develop because of a gene on the Y chromosome called SRY.

7週間前後で、男性器が発達し始めます。Y染色体上の遺伝子によるものです。SRYと呼ばれるものです。

It causes cells to become more specialized.

これは細胞の特殊化を引き起こします。

And these cells create testosterone, which, in turn, triggers the development of structures like the penis and scrotum, while other cells block female development by degenerating the female ducts.

そしてこれらの細胞はテストステロンを生成します。それが引き金となって、ペニスや陰嚢のようなの発達が起こります。一方で、他の細胞は女性の生殖管を退化させることで、女性の発達を妨げます。

However, in female development, because there is no Y chromosome with the SRY gene, these ducts stay intact and become the uterus, cervix, upper vagina, and the oviduct, with the help of estrogen, and chemicals secreted by the early kidney.

しかし、女性の発達において、SRY遺伝子を持つY染色体がないので、これらの管はそのまま残って子宮や子宮頸管、膣上部、卵管になります。化学物質の力を借りて、エストロゲンと初期の腎臓から分泌されます。

But it's not always that simple.

しかし、必ずしもそれほどシンプルではありません。

There are sometimes even rare combinations, like XXY, XXX, XXYY, etc.

XXY、XXX、XXYYなどの珍しい組み合わせが起こることもあります。

And even people with XX chromosomes that develop male genitals and characteristics, due to a piece of the Y chromosome breaking off and switching places to an X chromosome.

また、男性器や男性の特徴を発達させるXX染色体を持っている人でさえ、Y染色体の一部が分裂することによって

But sexual differentiation in the brain actually happens much later than gonadal differentiation.

And yes, although controversial, male and female brains have structural and functional differences between each other.

Studies have found that males generally have a larger cerebrum, cerebellum, and hippocampus.

While females have higher-density left frontal lobes and larger volumes in the right frontal lobes.

So what exactly do we see when we look at the brain of a transgender person?

Several studies have shown that transgender brains are both structurally and functionally more similar to their experienced gender identity than their biological sex.

One study found that transwomen, who, despite being assigned male at birth, had a smaller female-sized structure in the hypothalamus.

MRI scans also show the brain structures of transpeople to be more similar in thickness to their experienced gender and not their sex.

Finally, the pheromone androstadienone causes different hypothalamic responses in male and female brains.

And when individuals with Gender Dysphoria were exposed to it, the hypothalamic response match their perceived gender rather than their sex.

These studies help to highlight how masculinization or feminization of the gonads is not always the same as the brain.

And that there's a difference between your sex, or your anatomy and your gender, or how we perceive our own bodies.

There also seems to be a genetic component to transgender identity.

Looking at family histories, gender identity incongruence seems to run in the family.

Meaning they may be inherited.

The CYP17 gene, which controls the body's level of sex hormones, has a changed allele that is expressed frequently in transmen.

Although more research could be done, scientists are currently looking at over 3 million DNA markers for transgender identity to investigate any genetic link for being trans.

Even though scientific studies validate the experience of transgender people, they're still suffering from more depression and anxiety than the general public.

The risk of suicide is more prominent in transgender people who have been rejected by their family, discriminated in the workplace, or in healthcare.

Suicide risks seem to decrease after gender transitioning, suggesting that Gender Dysphoria can cause an extreme amount of emotional pain, even to the point of suicide.

If you, a family member, or a friend is suffering from Gender Dysphoria, there are a few links in the description for more information.

Thank you so much Gigi for being part of this video.

It means so much and we're happy that you are here to do this with us.

Ah, well, thank you guys for using your channel, your platform, validating transgender experiences with science, which just brings us closer to equality.

Absolutely!

If you guys wanna check out Gigi's channel, we'll put links in the description or on the screen somewhere.

Otherwise, you can subscribe for more science here, every week, and we'll see you next time.

Peace!