Yeahhhhhh… I have to imagine the original poster (not the OP here and not you; the screenshotted person) was purposely forcing this to be drawn out and discussed because they’re probably a literal Nazi. Almost anyone vaguely familiar with genetics and human genetics specifically (my undergrad was in bio) has read about inbreeding within the Jewish community (the Amish are another example often talked about. Obviously the European “royals” too, but fuck them).

It’s useful in a genetic/biological/medical sense, which is why these studies even exist, but outside of the direct professional and academic communities that research this stuff to improve medical treatments and such it’s mostly just used by Nazis to… “prove” whatever it is they’re seeking to prove.

Years back some white supremacists were trying to use a study about lactose tolerance/intolerance around the world to “prove” white people were superior because many Europeans can drink and digest milk without issue. They seemed unaware that while certain ethnic groups do absolutely tend towards lactose intolerance, that has no correlation with skin color or whatever the hell they were trying to tie it to. Skull shapes and shit.

They also tried (somewhat famously) to tie intelligence directly to genetics via “race” and ethnicity. There was even a fun little book written in the 90s, IIRC, but even more recently in the last couple decades as the field of human genetics has exploded there’s been a bunch of studies on human intelligence and what genes might or might not contribute to intelligence. I admit to having last read into the subject as part of a “Human Evolutionary Genetics” course about… four? years ago, but the conclusions then were basically summed up like: “there is no “intelligence gene(s).” Like we’ve discovered across all fields of genetics, most of the phenotypic traits “we” took as meaningful or attributable to genetics in some capacity are incredibly complex, not attributable to one or even several genes, but rather a currently unknown (maybe never known) number of genes and how they’re expressed depending on environmental factors.” So, basically, even if we accept on the surface level that some people are more intelligent (good luck defining intelligence), it can almost always be tied directly back, at the population level, to… hey, material conditions! People who have the proper caloric intake, especially as children, and have access to proper medical treatment, education, shelter, etc. grow up to their full potential, which it turns out, is pretty much exactly the same across all populations of humans. It’s just “funny” how racist white people love to compare the (made up, bullshit) IQ tests, etc. of white kids vs kids in a country that was in just the last century under colonial rule and still hasn’t been freed. They seem to conveniently mistake “kids who have all their needs met are healthier and more able to study and learn” with “material conditions? No, no! It is simply the superior Aryan brain!”

Anyway, TLDR, when I see people citing genetic studies outside of medical circles I get one of those bright red “!” over my head, a loud pinging noise goes off in my brain and I go “huh?!”