Looking no different from ordinary foals, docile with honey brown coats and white facial patches, they happily spend their days munching alfalfa in a cordoned-off pasture in rural Buenos Aires province.
But these five 10-month-olds are the world's first genetically edited horses: cloned copies of a prize-winning horse named Polo Pureza, or Polo Purity, with a single DNA sequence inserted using CRISPR technology with the aim of producing explosive speed.
Kheiron Biotech, the Argentine company that created the horses, says gene-editing has the potential to revolutionize horse breeding.
While cloning creates a genetically identical copy, CRISPR functions as a sort of genetic scissors to cut and customize DNA. The company, which specializes in equine cloning, used CRISPR to reduce the expression of the myostatin gene, which limits muscle growth. The idea was to increase the muscle fibers that allow for powerful movements and so transform the horses into sprinters.
But polo isn't letting them in so fast.
