Scientists claim to have cited the fastest case of human evolution. A study between the genomes of Tibetan and Han Chinese peoples have led scientists to identify a difference in genes that allows Tibetans to live at very high altitudes without experiencing altitude sickness. The study identified at least 30 genes that had undergone evolutionary change in the genomes of Tibetans. The biologists at the Beijing Genomics Institute cite that the split between the Han Chinese and the Tibetans happened only 3,000 years ago, meaning that this would be the most recent case of evolutionary change. However, archaeologists argue that the split happened no less than 7,000 years ago, which would put this case on the playing field with the evolution of genes for lactose tolerance in adults.
The study was completed by a group of biologists who analyzed the genes of 50 Tibetans who live at altitudes of 14,000 ft above sea level and 40 Han Chinese who live 160 ft above sea level. About 30 genes were found to be rare among the Han but common to the Tibetans. This difference indicates that the gene common to the Tibetan people is due to natural selection. The favored version of the gene, HIF2a, found in Tibetans, allows for fewer red blood cells which prevents the blood from thickening as the body tries to counteract the low oxygen levels by producing more red blood cells. This variation of the gene indicates how Tibetans can live at such high altitudes without suffering altitude sickness.
On an interesting side note, a major social concern regarding the implications of this genetic difference between Tibetan and Han Chinese stems from a long struggle for Tibetan people to achieve political autonomy. Researchers hope that this study doesn’t impede Tibet from accomplishing this autonomy “given that it is cultural history and language, not genetics, that constitute a people”, as stated by Dr. Nielson.
This is article is interesting because it shows the latest evolutionary change. However, I think it also implies the fact that genetic variation between these two groups results from the changing environmetal factor. There can be a possibility of this being true. So, possibly, even now people can adapt to this change in there genomes by living at different altitudes because people who live in different countries have alot of differences between their genomes and culture. Again, this shows the impact of the environment on our genes. All in all, it is very interesting and makes you think whether there will be problems for the two groups that belong to the same culture and society.
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