Science Matters

(5/2022) I want to tell you about my transgender grandson, but first I must back up and give you a sense of how I came to think about people like him.

Like most of you, I grew up thinking that people came in just two sexes—male and female—and all the members of each sex knew that they belonged to the sex indicated by their genitals and behaved pretty much the same way toward the other sex.

Then I learned about homosexuality. Labeled many decades ago as a perversion, it was thought to be a choice. Research, however, showed that sexual orientation was built into the brain. Somehow a switch in the anatomical development of gay and lesbian brains, like a switch on a railroad track, steered some part of the growing brain down one path instead of another. If not for something unusual in their rearing (smothering mothers, was one hypothesis, long since discarded), they would be just like everybody else. Eventually it became clear to researchers that homosexuality was not a product purely of environment and not a choice, but something built into the brain that could show up even in young children.

There are many more switches in the human brain’s growth and development than scientists once assumed. There are switches after switches. One set of switches, it appears, can make a toddler a musical prodigy, playing Mozart on the piano in kindergarten. Another path of brain development yields a gift for mathematics. Or chess, and so on. Most of us, however, simply grow up average in everything. So it seems to be with sexual orientation. The part of the brain that feels romantic attraction can turn out to focus on the same sex.

I had come to appreciate the research showing all that and then learned about yet another condition that psychiatrists and psychologists now call gender dysphoria. The official manual used by psychiatrists to classify mental conditions defines that as "a clinically significant distress or impairment related to a strong desire to be of another gender," especially in a world that does not accept such desires as natural. Kids with this condition are deeply unhappy when their brain tells them they are one gender and the world treats them as another. The suicide rate among these young people is very high. In one study about 40 percent of trans boys report having tried to kill themselves.

Let me back up again. As should be clear, the human brain is not simply one homogeneous structure like chocolate pudding but, instead, is made up of many different substructures, more like a salad. There is a part of the brain that tells us our gender, and it is entirely different from the organs of our embryonic bodies that guided formation of our sex hormones and our genitals. Sex and gender are not the same thing.

In other words, our brains are aggregations of different neurological components, each with its own function and effect. There is a tiny region that controls the right index finger. A different region handles our ability to speak, which is different from the part that understands the speech of others. There is a part of the brain that receives signals from the eyes and shows us the world outside our heads. There’s a place that records the name of a childhood friend whom we haven’t seen in decades. And so on. The separate parts often communicate with one another, but some parts function quite independently.

Unless you keep all this in mind, it’s hard to appreciate how a person labeled at birth as a boy or a girl might grow up with a component in the brain that tells them they belong to the other gender or to neither. It’s a component that developed independently of the genes for forming sexual anatomy. Usually, we inherit both together and they are in synchrony, but sometimes not.

We have no problem understanding that a child could inherit his father’s blue eyes and his mother’s curly hair. But if a child has the genital anatomy of one sex and the personality—including self-image—of the other, that challenges our assumptions.

Scientists have not yet found specific genes or parts of the brain that determine gender, but they have found some clues during autopsies. I’ve reviewed some of the scientific literature on this and learned, first of all, that there are small differences between the brains of men and women who are not transgender. Interestingly, the brains of transgender people often more closely resemble those of the average person of the opposite anatomical sex.

One of the differences—just to show you how detailed this brain anatomy is—involves "the central subdivision of the bed nucleus of the stria terminalis and the third interstitial nucleus of the anterior hypothalamus."

I learned much of this only after learning about my transgender grandson. This is a person, now 18 years old, whom we all thought to be a girl throughout most of childhood. But as a pre-teen she (as we then spoke of her) was deeply troubled. She would fly into rages, refuse to get out of bed to go to school, be angry or sullen with her parents. Years of psychologists and psychoactive drugs had no good effect. She was one deeply disturbed teenager, especially as her body became more obviously female.

Then it came out. This youngster had felt for years that "she" was a "he." This "girl" told us that she had always felt she was a boy. When we all accepted this news and assured him (as we now speak of him) of our love—there was a profound personality change. Overnight, this troubled teenager turned into a happy, polite, intelligent, well-behaved delight to have around. The change has stuck for the last few years. He has been taking testosterone and another drug to block estrogen. His voice has lowered a bit. He is happy at school. He has lots of friends. He has an after-school job that he loves. And he is considering which colleges to apply to.

Are we all prepared to accept this young man and the others who have come out as the gender that lived inside them? There are hundreds of thousands of others around the country. Is hostility toward transgender people a new recognized realm of prejudice in our society?

Interestingly, the transgender condition has long been accepted in traditional cultures on several continents, even though their westernized governments enact laws against it. Doctors now understand it is real. The Pentagon regards it as real. It’s real.

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