Scientists make clot breakthrough

Vitamin K is found in vegetable such as broccoli

Scientists have made a breakthrough in the treatment of potentially fatal blood clots.

German and UK researchers looking at the key role played by vitamin K in the formation of clots have pinpointed a gene essential for its production.

Imperial College London researchers, writing in Nature, said it could pave the way for more effective blood thinning treatments for those at risk.

The formation of blood clots can lead to heart attacks and strokes.

People who are at high risk of experiencing blood clots include those who have had heart attacks, have coronary artery disease, irregular heart beats, or those who have had heart valve replacement therapy.

For those who are not at high risk, vitamin K's clotting properties are beneficial.

A vitamin K injection is given to most babies shortly after birth.

This is to guard against a rare disease called Vitamin K deficiency bleeding, which occurs in approximately one in 10,000 babies.

Gene study

In the study, led by scientists from the Medical Research Council Clinical Sciences Centre at Imperial College, found a gene called VKORC1 controls the production of a protein which itself is essential for vitamin K - found in green vegetables such as broccoli and spinach - to play its role in clot formation.

Pinpointing that gene may help the development of drugs which would stop the vitamin playing its role - and therefore prevent clots forming.

A greater understanding of how warfarin works to reduce the risk of clotting should help to improve the management of cardiovascular disease Judy O'Sullivan, British Heart Foundation,

Researchers studied the genes of warfarin resistant rats and patients, and compared them with the genes of families with an inherited disorder in handling vitamin K which stops them forming clots properly.

A mutation in the VKORC1 gene was found in all three groups.

Warfarin is currently the best treatment for patients at risk from blood clots.

It is known that warfarin inhibits the action of vitamin K by targeting the protein, thinning the blood and preventing the formation of life threatening blood clots.

But scientists do not understand how this happens.

'Exciting discovery'

Identifying the gene will help scientists understand the link between the protein and vitamin K.

Professor Ted Tuddenham, of the MRC Clinical Sciences Centre, said: "This is an exciting discovery. Patients are treated with warfarin because we knew it prevented the action of vitamin K and therefore the formation of life threatening blood clots.

"However, we haven't been able to explain how this takes place.

"Pinpointing the target of warfarin will help us find out more about how vitamin K works.

"And this may lead to the development of more effective blood thinning treatments for all those whose health is at risk from the formation of blood clots."

Judy O'Sullivan, a cardiac nurse at the British Heart Foundation, told BBC News Online: "A greater understanding of how warfarin works to reduce the risk of clotting should help to improve the management of cardiovascular disease."