Calf was cloned with extra genetic material that ‘switches off’ the protein allergen
Scientists have created a genetically modified (GM) cow that produces milk with low levels of a protein known to cause allergic reactions in a significant proportion of children. The researchers believe it could one day lead to the sale of “hypoallergenic” milk from herds of GM cows.
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.