21.   Earlier studies have found that youngsters living around electromagnetic fields created by power lines have an increased incidence of childhood leukemia.

22.   For example, tons of leaves from a Madagascan periwinkle plant are harvested yearly to make precious ounces of a powerful drug against childhood leukemia.

23.   For instance, a drug called mercaptopurine is an important treatment for childhood leukemia.

24.   In Madagascar, researchers are using the rosy periwinkle found in the rain forest to treat childhood leukemia.

25.   No one knows what causes ALL, the most common form of childhood leukemia.

26.   No one knows what causes childhood leukemia.

27.   Scientists in Britain have been debating whether radiation causes childhood leukemia for many years.

28.   Researchers at the University of Toronto reported Tuesday that they had found an increase in childhood leukemia.

29.   The government said Monday it will study new research that links childhood leukemia with electromagnetic radiation from television transmission towers.

30.   This kind of mutation is caused by a particular enzyme, and it is often found in childhood leukemia and lymphoma.