NZ-assisted cow genome holds hope for medicine

New Zealand scientists are part of an international team that has sequenced the cow genome, work tipped to revolutionise breeding techniques and lead to more efficient milk and beef production.

It could also lead to breakthroughs in medical treatment for human diseases.

A team of 300 researchers from 25 countries have spent six years mapping and analysing the genetic make-up of a Hereford cow, named L1 Dominette, which lives on a research station in Montana, in the United States.

The results, published in Science, could lead to the ability to fast-track the meat and dairy industries' efforts to improve stock, as quickfire DNA testing could replace selective breeding programmes that span years.

Similar techniques could help produce a cow with a smaller environmental footprint, particularly one that produces less greenhouse gas.

The scientists meticulously mapped the 2870 billion DNA building blocks that provide the code for the cow's 22,000 genes (about 14,000 of which are common to all mammals, including humans).

Using Dominette's genetic data as a baseline, scientists then did comparison genome sequencing for six more cow breeds to look for variances.

The analysis revealed cows have extra genes dedicated to the operation of their immune system, which gives them the resilience to a wider range of micro-organisms than humans could cope with.

Cows cannot catch malaria, and it is hoped a complete understanding of their genetic code will point to possible new treatments for humans.

A consortium of AgResearch, Dairy InSight and Agritech Investments, invested US$1 million ($1.8 million) in the US$53 million ($94 million) project which began in 2003.

In return, the investment allowed New Zealand early access to data and, crucially, influence in the decision to prioritise the bovine genome definition over that of other species, said AgResearch scientist John McEwan.

"New Zealand will benefit greatly from this research due to its economic dependence on products from ruminants," he said.

This research has already had a major impact on New Zealand farming systems, notably in speeding up

genetic progress in improving dairy production. The sheep industry has already benefited from the genomic information as sheep and bovine genomes have features in common.NZPA

- NZPA