The genetic trick that helped humans ride horses

About 4,500 years ago, humans have reduced a bond that would form the history of our gender. Horses domestication led to great developments in transportation, hunting and war, which literally carries human society to the modern era.

Despite how human horses for humans were, scientists still have many basic questions about their domestication. A new research was published on Thursday August 28, in the magazine sciencesIt provides a new insight into the genetic transformations that helped them become taming and abandoning. The results not only show the history of the human association and human animals, but also can also help in directing and preserving horse breeding efforts today, according to researchers.

“By traveling again in time, you can (you can see) the effect of these reproductive practices on the modern world,” said the co -author Ludovic Orlando, director of research at the French National Center for Scientific Research and head of the Anthropology Center in Toulouse, to Gizmodo.

Old DNA evidence

Orlando Laboratory has spent the past fifteen years in the sequence of old horses genes, accurately dating back nearly a million years until the nineteenth century. For this study, he and his colleagues analyzed hundreds of genomics from a period of 6000 years. They identified 266 genetic marks related to the main features such as behavior, coat color, body shape, movement, athlete, and the ability of the disease to see the effect of selective reproduction over time.

The researchers found that about 5,000 years ago, during the early stages of horse domestication, he preferred selective education a genetic region (or place) linked to the ZDPM1 gene. This gene is a collection of behavior known in mice, indicating that taming was one of the first steps towards domestication of horses.

After about 250 years, humans began to choose extensively for GSDMC, which is the DNA area associated with the body’s emphasis on horses, spine, coordination, and strength in mice. This timing is in line with the “overlapping bottleneck”, when selective reproduction increasingly led to a sharp decrease in genetic diversity.

“The choice was not only very strong, but the timing was a sensation,” said Orlando.

Re -writing the history of the local horse

For more validation of the GSDMC function, co -author Lin Jiang, a professor at the Chinese Academy of Agricultural Sciences and has long been collaborating in Orlando, modified this DNA in mice. She and her colleagues used CT scan to search for physiological changes and make strength and coordination tests.

The modified mice have proven that they are much stronger and displayed mobility, which reflects the changes in the phenotype of horses that support horseback riding or carry more heavier loads on their backs.

Orlando said that showing these biological effects and linking them to the point during selective education that immediately preceded the globalization of domesticated horses “provokes the mind.” Moreover, the results contradict a long -term hypothesis that humans have begun to domesticate horses by choosing a varied coloring, making it easy to dismantle.

“What was surprising to me in our data is that we do not see evidence that the color is the trigger at first,” said Orlando.

The detection of genetic changes that formed horse domestication also helps scientists understand its horses today. “We have realized that about 16 % of the genetic diversity of horses has been lost in the past 200 years, simply due to the way we have been born since the nineteenth century,” said Orlando. He added that ancient DNA analysis can tell a lot about history, but it can also direct modern education practices.