The calf
had been cloned and
genetically engineered with an extra piece of genetic
material that switched off its natural gene for producing a
milk protein called beta-lactoglobulin, which is not present
in human milk and causes allergies in some young children.
Tests on the
cow's milk showed that it
contained less than 2 per cent of normal levels of beta-lactoglobulin
and was far richer than usual in other kinds of milk
proteins, such as the caseins used in cheese-making. The
researchers also believe the GM cow's milk will also contain
higher concentrations of calcium than ordinary milk.
The cow,
however, was born without a
tail which is a rare congenital abnormality. The scientists
believe this was a result of the cloning process, similar to
that used to create Dolly the cloned sheep, rather than the
GM technique used to eliminate the milk protein.
