What genetics has taught us about the breed

While the American president Donald Trump aims at the Smithsonian Institution for “anti-American ideology”, Adam Rutherford examines what the science of genetics has taught us about the race.

But despite this fundamental discovery, which has only been strengthened by human genomes continued, race and ethnicity are still often deployed to categorize human populations as distinct biological groups. These are views that can be found circulating in pseudoscience on social networks, but they also slip into scientific research And health systems.

It is even more disturbing when this thought finds its way in the corridors of the government.

The order is part of a broader attempt to shape American culture by eliminating “inappropriate, divided or anti-American” ideologies of the institute museums. He says: “The museums of the capital of our country should be places where individuals will learn – not to be subject to ideological indoctrination or to division stories that distort our common history.”

The exhibition itself is criticized in the text to promote the idea that “race is not a biological reality but a social construction, declaring that” the race is a human invention “”. The order offers exposure as an example of a “harmful and oppressive” change in the story depicting American values.

This is the point where people like me, a geneticist specializing in the history of racial science, become a little upset.

The problem here is that the sentence cited in Smithsonian is 100% correct. It is neither controversial in science nor in history.

The human variation is, of course, very real. People are different, and we can see these differences in skin pigmentation, in hair color and texture and in other physical characteristics. These differences come together in places around the world: people from the same region are more similar than people from other regions – so far, so obvious.

In the 18th century, these traits were the main determinants of a new fashion to categorize humans in allegedly scientific terms. The Swedish botanist Karl Linnaeus is legitimately credited as the father of modern biology, as he gave us The classification system that we still use today: genus and species. Each living being is appointed according to this system, for example bacteria Escherichia colior the lion, Panthera LeoOr GorillaWhich probably doesn’t need to explain.

We are Homo sapiens – Wise people. But in his fundamental work Naturae systemsLinnaeus introduced another classification level for usmainly designated by that the most visible of human features: pigmentation. Linnaeus gave us four types of humans, grouped by continental locks: Asiaicus – People with “yellow skin” and straight black hair; Americanus – Aboriginal Americans, with “red skin” also with straight black hair; African – people “with black skin” with curls tight in their hair; And European – “white skin” with blue eyes.

These designations are clearly absurd – none of the colors is correct, even if you have adopted the obviously incorrect view that millions of people share the same skin tones even in these categories. But the roots of racing designations that we still use today are visible in these labels. Some of these terms fell from social acceptability and are considered racist. But we always use “black” and “white” as descriptors for millions of people, none of whom really have black or white skin.

Even if this palette of colors was true, the original descriptions of Linnaeus only started with physical features. What he included in subsequent editions of Naturae systemswhich has become the Base of scientific racismwere behavior representations. Asiaicus were described as “haughty, gourmet and governed by opinions” while Americanus was labeled “stubborn, zealous, regulated by customs”. African Women were designated as “without shame” while the two sexes would be “cunning, lazy and governed by Caprice”. He described Europaeus Like “sweet, acute, inventive, governed by laws”.

From any definition at any age, these claims are racist and fully incorrect.

Of course, in the examination of history, we must be wary of judging people of the past according to our own standards. But as a fundamental text of modern biology, the introduction of a classification system for man who is ridiculous, racist and, above all, hierarchical, would leave an indelible brand over the centuries that have followed.

Over the next 200 years, many men would seek to refine these categories with new measures, including pseudoscientific interpretations of craniometry or skull measures. They have never settled on a final response on the number of breeds that there are – none of the characteristics that were used is immutable, or exclusive to people to whom they were supposed to be essential. We call this ideology “racial essentialism”. But all the many projects have put white Europeans as superiors to all the others.

It was the biologist Charles Darwin who began to undo these ideas, recognizing in his 1871 book Man descent that there was much more continuity in the features between the people who had been designated as discreet races. At the beginning of the 20th century, molecular biology entered the scene and the era of genetics dismantled the biological concept of the race.

As we have started to see how the genes are shared in families and populations, we have seen that the similarities come together in a group, but these groups do not line up with long -standing attempts to classify the races. The true metric of human difference is at a genetic level. In the 20th century, when we started to unravel our genomes and observe how people are similar and different in our DNA, we have seen that the terms used for several centuries had an insignificant relationship with underlying genetics.

Even if only a small percentage of our DNA differs between individuals, the genome is so large and complex that there is great diversity. Geneticists still work at Decrave how it changes people’s healthFor example. But these genetic differences do not delimit in the sense of what we call the race. They follow the ancestral lines, can differ by Geographic location and can be traced through Historical migration models.

However, for historical reasons, we continue to refer to the Ethiopians and the Namibians under the definition of the race of “black”. Or take the African-Americans, people were largely descended from Africans reduced to the new world: the sequencing of the genomes of black Americans reveals echoes of the history of transatlantic slavery. They have not only mixed the genetic ancestry of the handful of West African countries from which their ancestors were taken, but also significant quantities of European white DNA. This reflects the fact that the owners of slaves had sex – many of which would not have been consensual – with slaves.

Consequently, the simple categorization of the descendants of slaves as “black” also has no biological sense. They are genetically diverse in themselves and different from the African ancestors from which they come. Gathering them has no scientific sense.

It is therefore by consensus, use and history that we continue to use the term “black”. This is what we mean by a social construction. The concept of race has little use as a biological taxonomy. But it is extremely important socially and culturally. Social constructions are the functioning of the world: money and time are both socially built. The value of a book or a dollar is applied by agreement against goods and services. Time passes infallibly, but the hours and minutes are fully arbitrary units.

The media immediately started to seek a reason which reified a biological version of the race, sometimes focusing on the metabolism of vitamin D, which is linked to the production of melanin, and has effects on viral infections. Some studies have shown that lower levels of Vitamin D has teamed up with sensitivity to a coco Among the blacks. But it is a correlation and not a cause.

This is why genetics played such an important role in the dismantling of a scientific justification of the race and the understanding of racism itself. And that’s why the last declaration of Trump’s White House is disturbing a lot in the scientific community.

Trump frequently talks about genetics aspects to assert political points. One of the opinions he has expressed several times is that some people, and predictably, are genetically superior. “You have good genes, you know, right?” He said in September 2020 in a minnesota rally – a state that Over 80% white. “You have good genes. A large part of the genes, isn’t it, you don’t think? You have good genes in Minnesota.”

Likewise, in the successful campaign in 2024, he has denounced immigrants as having “bad genes”. It is difficult for someone who studies genes – and the strange and sometimes disturbing history of genetics – to understand even what could constitute a “bad” or “good” gene.

Ours is perhaps a pernicious story, but the trajectory of genetics has been that which tends towards progress and equity for all, as consecrated in the declaration of independence.

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