An international consortium of scientists has justsequence the genome of the pig and the wild boar? his wild “cousin” – and has come to the conclusion that both species have much in common with humans. For example, they are globe-trotting, adaptable and invasive, sometimes damaging their own habitat, and easy to seduce with food. However, they also present important differences, such as that their olfactory genes outnumber those of humans and dogs, and yet their sense of taste is almost non-existent. Researchers estimate that there is84% genetic similarity between pigs and humans.
As published by the magazineNature, the study authors analyzed the genome of a farmed pig (Sus scrofa domesticus) and compared it with those of ten wild pigs from different parts of Europe and Asia. They also contrasted similarities and differences with the mouse, dog, horse, cow and human genomes.
Understanding the origins of the modern pig, “is important because we breed these animals to try to respond to the demand for food in an increasingly efficient way, as well as trying to make them resistant to common diseases in swine and emerging pathologies”, explained Alan Archibald, a researcher at the Roslin Institute in Edinburgh and a co-author of the study.
In addition, the similarities found with the human genome in terms of diseases suggest that it could become a good model to study certain pathologies and test treatments, specifically in relation toobesity, diabetes, dyslexia, Parkinson’s disease, and Alzheimer’s. Finally, it must be taken into account that these animals are considered a possible source of xenotransplantation (transplants of organs from other species).
Hybrid pigs
The consortium of researchers, which has Spanish participation, has made it possible to date thatthe separation between the Asian and the European wild boar occurred a million years ago, approximately. A little later, at least 10,000 years ago, man domesticated the pig from the wild boar. This domestication occurred independently in multiple locations, and in both Europe and China.
Therefore, when Marco Polo arrived in China in the thirteenth century, he already found domestic pigs, but whose origin was completely different from what he knew of European pigs. But the most interesting thing is that, with the trips of the Portuguese to Asia and, above all, with those of the English from the 16th century, Chinese pigs began to be imported to Europe and they began to be crossed with European pigs.
At the time, Chinese pigs were imported because they were more docile and, above all, much fatter than Europeans. These hybrid pigs, in turn, gave rise two centuries later to the international pig breeds that we know today. The researchers say that although it was already known, it is now quantified precisely: approximately30% of the genome of international breeds is of Chinese origin.
