They really were living to be 900 years old, and there's a lot of biological reasons why they could do that. In the original creation, there was no genetic load. There [sic] were not deformed chromosomes, and they didn't suffer under the... You know, your gene code now is a copy off a copy off a copy off a copy who knows how many times of Adam. And the fact that it even works at all is pretty amazing. After all this copying process it's been through and plus the hostile environment, we, and the extra things we throw at it.

Coast-to-Coast AM interview (August 2-3, 2000)