A study shows that genetic inheritance plays a vital role in the susceptibility of leukaemia in children with a particular gene mutation.

This revelation has brought the researchers a big step closer to understanding the complex process by which acute lymphoblastic leukaemia (ALL) - the most common form of cancer in children - develops.

Inherited variations in genes was pinpointed to control the development of lymphocytes, white blood cells that play an important part in the body's defenses, by comparing the whole DNA genome of almost 1,000 British children with the disease against children without it, found scientists at the Institute of Cancer Research in Sutton, southwest London.

The study involved genome scans of 441 children suffering with ALL and it was observed that the same gene variants were found. Adults can also develop this type of leukaemia but it is mostly found in children from two to five years of age.

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, said Professor Richard Houlston, head of the Sutton institute's molecular and population genetic team.