25 July 1997
PPL develops sheep carrying human genes
PPL Laboratories has developed the first cloned animal to carry human
genes. A sheep called Polly will produce human proteins in her milk.
It opens up the field for producing identical flocks of sheep or other
farmyard animals able to produce human proteins in their milk for
treating diseases. PPL has done this by adding a human gene plus a marker
gene to the genetic material or nucleus. The nucleus was then introduced
into sheeps eggs from which the DNA had been removed.
The company is working with the Roslin Institute, near Edinburgh,
which recently announced it had cloned Dolly the sheep.
Professor Grahame Bulfield, director of the Roslin Institute, said: This
pioneering work will stimulate new opportunities in both agricultural and