Recent Human Evolution
Team Uncovers New Evidence of
Recent Human Evolution
ScienceNOW Daily News Feb. 4, 2008
Team Uncovers New Evidence of Recent Human Evolution
By Ann Gibbons
ScienceNOW Daily News
4 February 2008
http://sciencenow.sciencemag.org/cgi/content/full/2008/204/2
In the past 100,000 years, modern humans have colonized the far corners of the globe,
adapting to new environments as they migrated. Researchers have long assumed that these
dramatic transitions resulted in a sort of accelerated evolution in which genes for traits such
as skin color and stature changed rapidly to allow humans to survive in their new habitats.
Now, a team of French and Spanish researchers has found powerful new evidence to support
this idea, identifying 582 genes that have evolved differently in different populations in the
past 60,000 years, including a dozen that protect people from obesity, diabetes, hypertension,
and other diseases.
The team, led by population geneticist Lluis Quintana-Murci of the Pasteur Institute and
Centre National de le Recherche Scientifique in Paris, analyzed DNA of 210 individuals from
the database of Phase II of the International HapMap Project, an effort to identify variations in
human genes that cause disease. The researchers analyzed 2.8 million single nucleotide
polymorphisms (SNPs)--mutations in a single nucleotide in a genome that varies between
individuals or populations--from Europeans, Africans, and Asians. Then they sorted the
mutations by type, focusing on 15,259 nonsynonymous mutations, which alter amino acids
and thus a gene's function.
Using statistical analysis, the researchers found that some mutations occurred at such high
frequencies compared to other SNPs in the same populations that they must have improved
survival and reproductive success and been the result of strong positive selection pressure.
These mutations varied tremendously between populations, which counters a popular view
that many of the differences between populations arose by chance or were genetic variants
that hitchhiked along with other genes that improved reproductive success, says biological
anthropologist Henry Harpending of the University of Utah, Salt Lake City, and co-author of
another study of accelerated evolution.
Team Uncovers New Evidence of
Recent Human Evolution
ScienceNOW Daily News Feb. 4, 2008
Team Uncovers New Evidence of Recent Human Evolution
By Ann Gibbons
ScienceNOW Daily News
4 February 2008
http://sciencenow.sciencemag.org/cgi/content/full/2008/204/2
In the past 100,000 years, modern humans have colonized the far corners of the globe,
adapting to new environments as they migrated. Researchers have long assumed that these
dramatic transitions resulted in a sort of accelerated evolution in which genes for traits such
as skin color and stature changed rapidly to allow humans to survive in their new habitats.
Now, a team of French and Spanish researchers has found powerful new evidence to support
this idea, identifying 582 genes that have evolved differently in different populations in the
past 60,000 years, including a dozen that protect people from obesity, diabetes, hypertension,
and other diseases.
The team, led by population geneticist Lluis Quintana-Murci of the Pasteur Institute and
Centre National de le Recherche Scientifique in Paris, analyzed DNA of 210 individuals from
the database of Phase II of the International HapMap Project, an effort to identify variations in
human genes that cause disease. The researchers analyzed 2.8 million single nucleotide
polymorphisms (SNPs)--mutations in a single nucleotide in a genome that varies between
individuals or populations--from Europeans, Africans, and Asians. Then they sorted the
mutations by type, focusing on 15,259 nonsynonymous mutations, which alter amino acids
and thus a gene's function.
Using statistical analysis, the researchers found that some mutations occurred at such high
frequencies compared to other SNPs in the same populations that they must have improved
survival and reproductive success and been the result of strong positive selection pressure.
These mutations varied tremendously between populations, which counters a popular view
that many of the differences between populations arose by chance or were genetic variants
that hitchhiked along with other genes that improved reproductive success, says biological
anthropologist Henry Harpending of the University of Utah, Salt Lake City, and co-author of
another study of accelerated evolution.
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