TWO gene mutations that cause one of the commonest forms of childhood cancer have been discovered by scientists.
The breakthrough could lead to the development of new treatments for acute lymphoblastic leukaemia (ALL) which strikes down about 400 youngsters in the UK each year.
It accounts for about 80 per cent of leukaemia cases in children, and is most often found among two to five-year-olds. It is a cancer of the white blood cells, which are responsible for the body's immune system, and is deadly if left untreated.
Pharmaceutical scientist Dr Mary Relling and colleagues scanned the DNA of four hundred child patients and found variants in genes known as ARIDB5 and IKZF1 were common among them. Their study was published online.
Dr Relling, of St Jude Children's Research Hospital in Tennessee, said the ARID5B is important in embryonic development and IKZF1 is critical for the development of lymphoids, a type of tissue found in the lymph nodes.
She said: "Our findings indicate that inherited genetic variation contributes to the risk of childhood ALL and is likely to contribute to the development of some specific ALL subtypes."
Another study, also published online in Nature Genetics, looked at an independent group of almost a thousand children with ALL and identified the same genes as being linked with ALL.
Dr Richard Houlston, of the Institute of Cancer Research in Surrey, said the genes encode proteins that are involved in the development of white blood cells called B cells that produce antibodies to fight disease and are most commonly affected in ALL.
He said his findings show common gene mutations contribute to the risk of developing childhood leukaemia and provide new insight into its cause.
Dr Houlston added: "Acute leukaemia is the most prevalent paediatric cancer in developed countries, where it affects 30 to 45 per 1,000,000 children per year."