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Three groups of mutations which cause acute myeloid leukaemia, a cancer of the white blood cells, have been identified by scientists.

The researchers suggest their work on mice, , could lead to new treatments.

Two thousand people in the UK are diagnosed with acute myeloid leukaemia each year.

The charity Leukaemia and Lymphoma Research said the study offered invaluable insight.

Immature

During the illness, the bone marrow, which produces blood cells, starts to churn out immature white blood cells.

This changes the balance of the blood.

The white blood cells are not properly developed so they cannot fight infection and there are too few red blood cells to carry oxygen around the body.

The disease can be fatal within weeks if left untreated.

The research group at the Wellcome Trust Sanger Institute investigated how this form of leukaemia arises because they say there had been little progress in developing new drugs.

Three groups

The most common mutation implicated in the cancer is to the Npm1 gene.

By switching this gene on in blood cells in mice, the researchers were able to show that it boosted the ability of cells to renew themselves, which is a sign of cancer. Yet only a third of mice went on to develop leukaemia.

The researchers concluded other mutations must also play a part.

They randomly mutated genes in mice, with a technique known as insertional mutagenesis. By looking at mice which developed cancer, they could then trace which mutations were involved.

They found two additional types of mutation. One affects cell division and growth, while the other modifies the cell's environment.

Dr George Vassiliou, consultant haematologist from the Wellcome Trust Sanger Institute, said they had "found critical steps that take place when the cancer develops. Identifying the biological steps in turn means we can look for new drugs to reverse the process."

He told the ����ý: "Getting new drugs to patients could take decades, but what can happen sooner is using drugs which are already on the shelf, but in a more targeted way."

Dr David Grant, scientific director at Leukaemia & Lymphoma Research, said: "New designer drugs which target specific genetic mutations are proving increasingly effective in the treatment of blood cancers.

"This is a very important study as it offers an invaluable insight into the role of the most common form of mutation found in acute myeloid leukaemia. It explains how it develops and the other genetic factors that drive the leukaemia's growth.

"It offers a potential model for the development of new drugs for this terrible disease in the future."