Interviewer: Well, what are the broader implications of this concept of yours of molecular disease?
Do you envisage, for example, a kind of new medicine which will be based more fundamentally
on chemotherapy for example?
Linus Pauling: Yes, I would say so. I think that we shall be able to get a more thorough understanding
of the nature of disease in general by investigating the molecules that make up the
human body including the abnormal molecules, and that this understanding will permit
disease to be attacked - the problem of disease to be attacked - in a more straight-forward
manner, such that new methods of therapy will be developed.
For example, we are working now on a disease called phenylketonuria. Phenylketonuria
is a disease that involves a bad gene. Normal human beings have inherited two genes
from their parents that manufacture an enzyme - a special protein in the liver that
catalyzes the oxidation of an amino acid, phenylalanine, to form another amino acid,
tyrosine. Now, we ingest, we eat food containing phenylalanine all the time. An ordinary
protein is about five-percent phenylalanine. So that everybody gets a lot of phenylalanine
into his body by way of eating protein. He has to eat protein to build up his body.
This phenylalanine is in large part converted into another substance by the action
of the enzyme in the liver.
One person in eighty has only one good gene for this enzyme and then he has one bad
gene, the result of a genetic mutation. A bad gene that will not manufacture a good
enzyme. These people - we have been studying the activity of the liver of these people.
We give them some phenylalanine, and then we take a sample of blood and determine
what has happened to that phenylalanine in the course of one or two or three hours,
and we find that normal individuals are able to destroy, to change the phenylalanine
to tyrosine twice as fast as these people, one in eighty, who are the carriers of
one bad gene.