Evan Urquhart

Moving on to the paper itself. You can find the full text here: https://www.nature.com/articles/s41598-019-53500-y … (It's in Nature, which is among the most selective, high prestige scientific journals.)

The first thing to understand is that this article rests on a foundation of other literature. It takes as its starting point the previously existing evidence that gender dysphoria is a heritable trait.

I believe GD is heritable too, and I wrote a bit about that in an earlier thread. These authors focus on twin studies showing high heritability, while I made a more logic-based case for why I tend to believe it more than the alternative hypothesis.https://twitter.com/e_urq/status/1222166299893096448 …

How did they do this? Well, first they sequenced 30 trans people's DNA (13 trans men, 17 trans women). They compared that data to 88 cisgender people as controls, ad they further compared it to a database of common genes.

They found 441 rare variants of known genes through this method. They further winnowed those down by researching genes involved in sexually dimorphic brain development in animals.

They were left with 19 genes that both A) had a rare variant in at least one trans subject, and B) were associated with sexually dimorphic brain development.

If I've understood the paper correctly, none of the rare variants were the exact same in more than one trans subject, but in some cases multiple trans subjects had a rare variant of the same gene.

Like the Newsweek article, the study authors are quite careful to be respectful of the diversity in the trans community, and to acknowledge the potential dangers in how research like this could be used.

OK. So, now we understand the study, what it intended, and what was found. Are there any big picture takeaways from all this?

Big picture: Researchers have accepted the evidence that gender dysphoria is heritable/genetic and are proceeding to hunt for a mechanism (and getting published in Nature). They want to know not whether GD is genetic, but what role genes of sexual development might play.

Big picture: We are very far from having any idea how gender dysphoria is caused on a biological basis. (If a mechanism for was found, it might or might not be reason for worry. It's a long jump from finding a mechanism to eugenics, and the devil would be in the details.)

Big picture: Research on rare gene variants in transg subjects might increase our understanding of brain development, and whether/how sex plays a role in it. (Same caveats about worry here- this could have scary implications, but we're a long way from knowing that yet.)