Re: Good Mutations.

George Murphy (
Fri, 28 Nov 1997 21:48:53 -0500

Glenn Morton wrote:

> >I got into a discussion the other day about whether there ever are any
> >"good" mutations, the kind that evolution requires in order for changes to
> >occur. The only example I could think of had to do with sickle cell
> >anemia. Are there any examples of mutations that aren't harmful (aside
> >from the mutations to regions of DNA that don't do much)? Any help would
> >be appreciated.
> I don't have a reference on this, but there is a mutation in an Italian
> family which allows them to avoid the harmful effects of cholesterol. They
> can eat all the bad stuff and never have heart attacks. This is a good mutation.

We can't say that any mutation is "good" in an absolute sense,
for it depends on whether the result has a net benefir in a particular
environment. Again sickle cell is a classic example: The mutation is
on balance good for a population in heavily malarial areas, & on balance
bad for a population in an area where malaria isn't so much of a
George Murphy