News to delight dairy manufacturers and dismay opponents to genetically modified foods arrived this week with publication of a new study that reveals protein-rich milk from not only cloned but also genetically modified cows could cut cheese-making costs. The cloned cattle carry extra copies of the genes for two types of the protein casein, key for cheese and yoghurt manufacturers.
Researchers at the biotech company AgResearch in New Zealand set out to enhance milk composition and milk processing efficiency by increasing the ß-casein and k-casein concentration in milk.
Scientists, led by study leader Götz Laible, introduced additional copies of the genes encoding bovine ß- and k-casein (CSN2 and CSN3 respectively) into female dairy cows. The researchers then transferred the nucleus into unfertilised cow eggs. Of the 126 modified embryos, 11 cows survived until after weaning.
The results showed that nine cows produced milk with an eight to 20 per cent increase in casein, leading the scientists to suggest that such modification could have a very real impact on the functional properties of dairy milk.
Controversial at the best of times, milk from genetically modified cloned cows is certain to stir up a vociferous opposition. While most scientists believe that milk from cloned cows is no different to normal milk, they are less certain about the safety of milk from genetically modified cows. The team in New Zealand did stress the need for further testing in order to establish the safety of the milk.
Full findings are published this week in Nature Biotechnology.