Scientists believe the suppressor gene can be inactivated by tobacco, viruses, pollution or diet.

More recently, scientists have discovered a class of "anti-oncogenes," or suppressor genes that appear to protect against cancer.

In 1992 oncomice with tumor suppressor genes knocked out were generated.

This suppressor gene is also called elongin binding protein and G7 protein.

The most well known of these tumor suppressor genes, known as p53, has been related to a panoply of common cancers.

A mutation to only one tumor suppressor gene would not cause cancer either, due to the presence of many "backup" genes that duplicate its functions.

Several research groups have suggested that other, "suppressor" genes may limit the expression of frame-pattern white spotting.

And once these suppressor genes are perturbed, growth rates can explode into cancer.

In theory, an oncogene turns cells malignant only if the suppressor gene has been damaged.

Damage to the suppressor gene can be environmental or hereditary.