1.   About half of those early-onset cases are caused by inherited mutations in the three genes.

2.   Fascinated by inherited mutations among rodents, he became convinced that they might offer a way to understand a genetic basis for cancer in humans.

3.   No inherited mutations were found in that group, said Morgan, but it was rare that both parents in the Japanese bombings were equally exposed.

4.   Such inherited mutations were uncommon in the general population, the researchers found.

5.   The mapping of the human genome, or genetic structure, may make it possible for researchers to detected inherited mutations that were not obvious before, said Setlow.

6.   Wallace has proposed that the inherited mutations are somehow related to mitochondria.