Gene Study Identifies 5 Main Human Populations

New York Times ^ | 12-20-02 | Nicholas Wade

[Pharmboy]

Scientists studying the DNA of 52 human groups from around the world have concluded that people belong to five principal groups corresponding to the major geographical regions of the world: Africa, Europe, Asia, Melanesia and the Americas.

The study, based on scans of the whole human genome, is the most thorough to look for patterns corresponding to major geographical regions. These regions broadly correspond with popular notions of race, the researchers said in interviews.

The researchers did not analyze genes but rather short segments of DNA known as markers, similar to those used in DNA fingerprinting tests, that have no apparent function in the body.

"What this study says is that if you look at enough markers you can identify the geographic region a person comes from," said Dr. Kenneth Kidd of Yale University, an author of the report.

The issue of race and ethnicity has forced itself to biomedical researchers' attention because human populations have different patterns of disease, and advances in decoding DNA have made it possible to try and correlate disease with genetics.

The study, published today in Science, finds that "self-reported population ancestry likely provides a suitable proxy for genetic ancestry." In other words, someone saying he is of European ancestry will have genetic similarities to other Europeans.

Using self-reported ancestry "is less expensive and less intrusive" said Dr. Marcus Feldman of Stanford University, the senior author of the study. Rather than analyzing a person's DNA, a doctor could simply ask his race or continent of origin and gain useful information about their genetic make-up.

Several scientific journal editors have said references to race should be avoided. But a leading population geneticist, Dr. Neil Risch of Stanford University, argued recently that race was a valid area of medical research because it reflects the genetic differences that arose on each continent after the ancestral human population dispersed from its African homeland.

"Neil's article was theoretical and this is the data that backs up what he said," Dr. Feldman said.

The new result is based on blood samples gathered from around the world as part of the Human Genome Diversity Project, though on a much less ambitious scale than originally intended. Dr. Feldman and his colleagues analyzed the DNA of more than 1,000 people at some 400 markers. Because the sites have no particular function, they are free to change or mutate without harming the individual, and can become quite different over the generations.

The Science authors concluded that 95 percent of the genetic variations in the human genome is found in people all over the world, as might be expected for a small ancestral population that dispersed perhaps as recently as 50,000 years ago.

But as the first human populations started reproducing independently from one another, each started to develop its own pattern of genetic differences. The five major continental groups now differ to a small degree, the Science article says, as judged by the markers. The DNA in the genes is subject to different pressures, like those of natural selection.

Similar divisions of the world's population have been implied by earlier studies based on the Y chromosome, carried by males, and on mitochondrial DNA, bequeathed through the female line. But both elements constitute a tiny fraction of the human genome and it was not clear how well they might represent the behavior of the rest of the genome.

Despite the large shared pool of genetic variation, the small number of differences allows the separate genetic history of each major group to be traced. Even though this split broadly corresponds with popular notions of race, the authors of Science article avoid using the word, referring to the genetic patterning they have found with words like "population structure" and "self-reported population ancestry."

But Dr. Feldman said the finding essentially confirmed the popular conception of race. He said precautions should be taken to make sure the new data coming out of genetic studies were not abused.

"We need to get a team of ethicists and anthropologists and some physicians together to address what the consequences of the next phase of genetic analysis is going to be," he said.

Some diseases are much commoner among some ethnic groups than others. Sickle cell anemia is common among Africans, while hemochromatosis, an iron metabolism disorder, occurs in 7.5 percent of Swedes. It can therefore be useful for a doctor to consider a patient's race in diagnosing disease. Researchers seeking the genetic variants that cause such diseases must take race into account because a mixed population may confound their studies.

The new medical interest in race and genetics has left many sociologists and anthropologists beating a different drum in their assertions that race is a cultural idea, not a biological one. The American Sociological Association, for instance, said in a recent statement that "race is a social construct" and warned of the "danger of contributing to the popular conception of race as biological."

Dr. Alan Goodman, a physical anthropologist at Hampshire College and an adviser to the association, said, "there is no biological basis for race." The clusters shown in the Science article were driven by geography, not race, he said.

But Dr. Troy Duster, a sociologist at New York University and chairman of the committee that wrote the sociologists' statement on race, said it was meant to talk about the sociological implications of classifying people by race and was not intended to discuss the genetics.

"Sociologists don't have the competence to go there," he said.

[tallhappy]

Here's a sampling of the political correctness agony that goes on in academia over the concept of "race:"

Which of those are biologists?

Answer: none.

Race is subjective. None of the blowhards arguing can be wrong or right fully. They are simply arguing semantics and personal opinion, not science or facts.

There are genetic facts which are that race cannot be determined or defined genetically. There are markers that can be clustered and compared to pre-defined populations that roughly correlate with geographic regions.

Unfortunately I realize you do not understand any of this.

[tallhappy]

In mammals, mitochondiral rna mutates at a fairly fixed rate.

How come you guys who hate and are obsessed with creationists never know anything about biology? It's a weird dynamic.

You are referring to the mitochondrial DNA, not RNA (and it should be capitalized).

[tallhappy]

I bet if they'd look specifically at North Africans, they'd have both European and African markers.

That was the case. That was one of the overwhelming findings -- that the markers are not static.

[tallhappy]

If there is no such thing as race, then there can be no affirmative action based on race.

If, on the other hand, racial differences do exist, some differences would be good for society and some differences would be bad for society. Some races would be taller. Some races would be more artistic. Some races would be more intellegent. Some races would be more civilized.

The first is true and a great point. The second is based on pure assumption, probably wrong.

[tallhappy]

Defining differences in race, even on a DNA scale, can only get a person in big trouble with the PC crowd.

No. The PC crowd want race defined. So they can advocate affirmitive action and "diversity" and all that.

It is the opposite of how you state it.

[tallhappy]

Here is the actual abstract. :

Science 2002 Dec 20;298(5602):2381-2385

Genetic Structure of Human Populations.

Rosenberg NA, Pritchard JK, Weber JL, Cann HM, Kidd KK, Zhivotovsky LA, Feldman MW.

Molecular and Computational Biology, 1042 West 36th Place DRB 289, University of Southern California, Los Angeles, CA 90089, USA., Department of Human Genetics, University of Chicago, 920 East 58th Street, Chicago, IL 60637, USA., Center for Medical Genetics, Marshfield Medical Research Foundation, Marshfield, WI 54449, USA., Foundation Jean Dausset-Centre d'Etude du Polymorphisme Humain (CEPH), 27 rue Juliette Dodu, 75010 Paris, France., Department of Genetics, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA., Vavilov Institute of General Genetics, Russian Academy of Sciences, 3 Gubkin Street, Moscow 117809, Russia., Department of Biological Sciences, Stanford University, Stanford, CA 94305, USA.

We studied human population structure using genotypes at 377 autosomal microsatellite loci in 1056 individuals from 52 populations. Within-population differences among individuals account for 93 to 95% of genetic variation; differences among major groups constitute only 3 to 5%. Nevertheless, without using prior information about the origins of individuals, we identified six main genetic clusters, five of which correspond to major geographic regions, and subclusters that often correspond to individual populations. General agreement of genetic and predefined populations suggests that self-reported ancestry can facilitate assessments of epidemiological risks but does not obviate the need to use genetic information in genetic association studies.

Within-population differences among individuals account for 93 to 95% of genetic variation; differences among major groups constitute only 3 to 5%.

Clearly this again confirms race is not genetically based or definable.

[bert]

In my reading of his works he maintained that there were no differences in human populations.

[muir_redwoods]

Sorry, you're simply wrong. The Neanderthals were the most recent distinct race in our species but all living people are one race. An analogy with dogs would be that there are many breeds but all are dogs. The wolfhound and the pekinese are the same race but different breeds. The term "race" is as misused as the term "theory" when the discussion is Darwin.

[PatrickHenry]

A press release from Standford on the same study: HERE.

[FreedomCalls]

A Japanese doesn't look much like a Vietnamese or a Siberian.

So you think you can tell them apart? Take the test.

http://www.alllooksame.com/frameset-register.html

[Pharmboy]

We share 96% of our genes with chimpanzees--clearly we are the same species according to your reasoning.

Look--races are geographic variants that are called sub-species when occuring in non-human animals. No big deal--that's just the way it is.

[Luis Gonzalez]

race¹
(click to hear the word) (rs)
n.

1. A local geographic or global human population distinguished as a more or less distinct group by genetically transmitted physical characteristics.
2. A group of people united or classified together on the basis of common history, nationality, or geographic distribution: the German race.
3. A genealogical line; a lineage.
4. Humans considered as a group.
5. Biology
   1. An interbreeding, usually geographically isolated population of organisms differing from other populations of the same species in the frequency of hereditary traits. A race that has been given formal taxonomic recognition is known as a subspecies.
   2. A breed or strain, as of domestic animals.
6. A distinguishing or characteristic quality, such as the flavor of a wine.

[Luis Gonzalez]

spe·cies
(click to hear the word) (spshz, -sz)
n. pl. species

1. Biology
   1. A fundamental category of taxonomic classification, ranking below a genus or subgenus and consisting of related organisms capable of interbreeding. See Table at taxonomy.
   2. An organism belonging to such a category, represented in binomial nomenclature by an uncapitalized Latin adjective or noun following a capitalized genus name, as in Ananas comosus, the pineapple, and Equus caballus, the horse.
2. Logic A class of individuals or objects grouped by virtue of their common attributes and assigned a common name; a division subordinate to a genus.
3. 1. A kind, variety, or type: "No species of performing artist is as self-critical as a dancer" (Susan Sontag).
   2. The human race; humankind.
4. Roman Catholic Church
   1. The outward appearance or form of the Eucharistic elements that is retained after their consecration.
   2. Either of the consecrated elements of the Eucharist.
5. Obsolete
   1. An outward form or appearance.
   2. Specie.

[Luis Gonzalez]

"A local geographic or global human population distinguished as a more or less distinct group by genetically transmitted physical characteristics."

Genetically transmitted physical characteristics.

Like for instance, skin color.

Tha's right, dogs are one species, with many breed (races).

BTW, black people are human, as are Asian, as are caucasians.

One species, three races.

[Doctor Stochastic]

We share 96% of our genes with chimpanzees--clearly we are the same species according to your reasoning.

Actually, Tallhappy's reasoning said no such thing. He made no comments about the percentage of genes shared among "races." You may wish to take an elementary statistics course to understand his point.

[tallhappy]

We share 96% of our genes with chimpanzees--clearly we are the same species according to your reasoning.

No. That was not my logic and also indicates you do not understand what it means to share 96% of genes with another species. Nor, apparently, do you understand the difference between marker and gene.

As far as race being an artificial construct based roughly on traits that can be be roughly correlated with geography, yes. That is my point and I am glad you do understand that, but I still think you grapple with it.

[tallhappy]

Thank you.

[Pharmboy]

Within-population differences among individuals account for 93 to 95% of genetic variation; differences among major groups constitute only 3 to 5%.

Clearly this again confirms race is not genetically based or definable.

This is what he said; he did not quote the study's conclusion which said the OPPOSITE, i.e. that genes follow geography and that race is indeed definable biologically.

Perhaps you need a biology course, a reading comprehension course and throw in one that deals with manners and civility.

[Pharmboy]

From the abstract:

Nevertheless, without using prior information about the origins of individuals, we identified six main genetic clusters, five of which correspond to major geographic regions, and subclusters that often correspond to individual populations.

That is, what reasonable, sentient humans think of as races. This was something Gould and his ilk argued against for years. You must understand in your biased little brain that the left does not ever try to be consistent--it is perfectly logical (for them, and you, I suppose) to argue against the existence of race, but believe in the legitimacy of affirmative action for "groups" or whatever.

[Pharmboy]

Clearly this again confirms race is not genetically based or definable.

You must be a follower of the great biologist Lysenko.