Brussels, 07 Aug 2003
Italian scientists have succeeded in producing the first cloned horse, and unlike previously cloned animals, the foal was born to her genetically identical mother.
The Halflinger foal, named Prometea, was born on 28 May, after a skin cell from her mother and an empty egg were fused in a laboratory and implanted in the mother's womb. All previous clones received their DNA from a donor unrelated to the female that was to give birth to them.
Prometea was produced by a team from the Laboratory of Reproductive Technology in Cremona, Italy. Team leader Cesare Galli told the journal 'Nature' that she is perfectly healthy and genetically identical to her mother.
This latest case of cloning contests the previously held belief that for an embryo to survive, it needs to be recognised as different by the mother's immune system. However, Prometea's birth has also demonstrated the difficulty faced by scientists when attempting to produce clones.
The researchers cultured 513 reconstructed embryos from the skin of an Arabian thoroughbred male, and 328 from the Halflinger mare. A total of 22 embryos went on to the blastocyst stage, and only 17 embryos were implanted in the wombs of mares. Only four of these developed, and of these four, Prometea was the only one to survive the full pregnancy.
The ability to clone horses could have a huge impact on horse racing and show jumping. 'The quality of the sport would be upgraded,' Professor Galli told Nature. 'It would be like putting ten Ronaldos against ten Beckhams.'