THE WESTERN PENNSYLVANIA HOSPITAL

INSTITUTE OF PATHOLOGY
PITTSBURGH, PENN’A

-
August 7, 1950

Dr. Joshua Lederberg
University of Wisconsin
Madison, Wisconsin

Dear Dr. Lederberg:

Down at the Baltimore Meetings, I was talking to Lindegren
in connection with some of the mutation phenomena in bacter-
jology, and quoting his own recent book on "The Yeasts,"

he felt, by way of analogy, that many of the things that
are called mutations among bacteria by geneticists cannot
be proved to be such; thus, he cited the behavior of his
own strain of red yeast, which constantly throws stable,
achromatic colonies. By using the out-cross, as I recall
he said, he was able to prove that this phenomenon is not

a real mutation, and compared similar situations in bacter-
iology, such as, let us say, mucoid colonies spontaneously
throwing smooth ones.

What I wanted to ask was, what slant you have on this sit-
uation, inasmuch as such matters naturally carry further
into the genetic field than I am able to go.

With kindest personal regards, I am

Sincerely yours,

 

RRM rbop