Gay Incels & Blackpillers Are Totally Wrong When They Say Short Men Are Subhuman.
Short people have an evolutionary advantage, study finds
[UWSL]TUESDAY, JULY 18, 2017[/UWSL]
A common mutation in a gene called GDF5, present in billions of people today, may have provided our ancestors with an evolutionary advantage against the extreme cold of the ice age by making us shorter. Unfortunately, the same gene responsible for shortening our limbs to conserve heat and protect us from frostbite is also associated with an increased risk for osteoarthritis.
The study was published this week in Nature Genetics.“A genetic change to a single letter in our DNA can spread rapidly through the human population if it provides a biological advantage”, says co-author Andrew Doxey, a professor of biology at the University of Waterloo. “This mutation represents human evolution across thousands of years, which in this case was driven by a massive migration. The fact that this selection shows up so prominently in our genetic code is profound.”
Human evolution from a desktop
GDF5 was first identified a decade ago from genome wide studies on height, but it was the evolutionary signature that intrigued the team most.
Other studies have found similar positive selection hotspots such as the gene that produces the lactase enzyme in the human gut, an evolutionary adaptation that coincided with the origins of farming and milk consumption.“There are these signatures of selection all across our genome that seem to have swept through the population relatively quickly,” says Doxey. “Just a fraction of them have been studied and this is a new one. No one has ever examined the effect of this particular genetic variant before."
But bioinformatics only identifies the locations that have undergone this selective sweep, not what the genes do. That’s where Terence D. Capellini of Harvard University, the study’s lead, and David Kingsley, a professor at Stanford, provided additional experimental evidence on mice using CRIPSR technology to confirm that GDF5 had a strong influence on height and how it works to suppress limb growth.
From there, Doxey and his colleagues added a new dimension to the study by globally mapping the proportion of the population containing the GDF5 variant that makes humans shorter.
The results were striking: in Africa, hardly any groups possess the variant, but as you move away from Africa, the proportion of the population with an active GDF5 gene becomes increasingly higher. Over fifty percent of the European and the Middle Eastern population have the variant; some parts of Asia show near 100 percent prevalence.
The long and short of human height
Although there are several factors that control height, the researchers found this particular mutation – a single change in one letter – is unique to humans.
Equally important to the researchers was how this gene seems to be associated with a 1.2- to 1.8-fold increase in the risk of osteoarthritis. This may be related to how the gene controls joint length versus the growing end of long bones.
This research was supported with funding from Natural Sciences and Engineering Research Council of Canada (NSERC), the Arthritis Foundation, National Institute of Health, the Milton Fund of Harvard, the China Scholarship Council, and the Jason S. Bailey Fund of Harvard.
