Study links inherited genes, leukaemia drug toxicity

In collaboration with the Press Association

A study has revealed that inherited variations in certain genes can affect the likelihood that children with leukaemia will be susceptible to the toxic side-effects of chemotherapy.

The side-effects experienced by some patients with acute lymphoblastic leukaemia (ALL) can be life-threatening and disrupt the delivery of treatment, increasing the risk of relapse.

Dr Mary Relling, senior author and chair of the pharmaceutical sciences department at St Jude Children's Research Hospital, said that the finding could therefore help to individualise chemotherapy in the treatment of ALL and cut the number of patients experiencing these side-effects.

"Such individualised therapy would eliminate the time-consuming trial-and-error approach to finding the right dose for a patient," Dr Relling explained.

"When the results of our findings are translated into routine clinical care, we should see less toxicity among children being treated for ALL."

The researchers, who have published their findings in the journal Blood, extracted the DNA from the healthy white blood cells of 240 patients and looked for 16 specific gene variations (polymorphisms) which are known to influence an individual's response to drugs.

They found that some of the 16 polymorphisms were linked to toxic side-effects in different stages of ALL treatment, while others caused more than one type of toxicity.

Dr Rochelle Long, director of the National Institutes of Health Pharmacogenetics Research Network, commented: "Scientists at St Jude and elsewhere have dramatically improved survival rates from childhood leukaemia, but it's still challenging to find the right dose for each patient.

"By finding specific genetic variations linked to how individual patients respond to therapy, this work will make medicines safer and more effective for everyone."