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HalfMooner
Dingaling
Philippines
15831 Posts |
 Posted - 08/18/2007 : 15:51:59
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According to an article in Cornell University's Chronicle Online: A Cornell study of genome sequences in African-Americans, European-Americans and Chinese suggests that natural selection has caused as much as 10 percent of the human genome to change in some populations in the last 15,000 to 100,000 years, when people began migrating from Africa.
The study, published in the June 1 issue of PLoS (Public Library of Science) Genetics, looked for areas where most members of a population showed the same genetic changes. For example, the researchers found evidence of recent selection on skin pigmentation genes, providing the genetic data to support theories proposed by anthropologists for decades that as anatomically modern humans migrated out of Africa and experienced different climates and sunlight levels, their skin colors adapted to the new environments.
However, the study found no evidence of differences in genes that control brain development among the various geographical groups, as some researchers have proposed in the past. |
The peer-reviewed paper in PLoS Genetics says: | In general, we find that recent adaptation is strikingly pervasive in the human genome, with as much as 10% of the genome affected by linkage to a selective sweep. |
Science in Africa has a popular article about the study. According to the South African-based site: | Overall, close to 10 percent of the Chinese and European-American genomes and only 1 percent of the African-American genome were linked to areas with evidence of recent selection. Since Africans have the greatest genetic diversity and the statistical method searched for areas where the majority of members within a population group have the same genetic changes, signs of evolution were much easier to detect in the less diverse European-American and Chinese genomes. |
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
Edited by - HalfMooner on 08/18/2007 15:55:12
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10% of human genome of recent origin, says study
