HARVARD MEDICAL SCHOOL
THE DEPARTMENT OF PHARMACOLOGY
25 SHATTUCK ST., BOSTON 18, MASS.

December 29, 1952.

Dr. Joshua Lederberg
Department of Genetics

The University of Wisconsin
College of Agriculture,
MADISON 6, Wisconsin.

Dear Doctor Lederberg:

_ Thank you for your interesting letter about the
Harvard strain of E. coli. I am sure that with your
facilities and experience you will be able to straighten
out the situation very quickly.

I should comment that you will probably find that
what you describe as the A type of colony from the Harvard
slant is simply one of the mutants that happendto appear
in large number in that particular getee slant. The slant
I sent you came from a very carefully done single colony
isolation only a few weeks before and so it is most unlikely
that the A form represents anything but what I suggest.

Your comment that it would be surprising for variants
like Harvard A and B to have arisen from MSFB was interest-
ing because while I have no personal evidence that such was
the case, it seems that there is little doubt of the fact
that MSFB was really a parent of our present Harvard strain.
If this point should interest you further, I could easily
send you other parent strains such as the original Mueller
Strain that has been in his ice chest for many many years.

I certainly did not mean to cast any aspersions on your
mechanisms of transduction. But unless you have become harden-
ed by prolonged contact with these things, I think you will
agree it is a pretty remarkable business.

With best holiday wishes to you and your wife from both
of us.

Sincerely,

A. Goldstein, M.D.
Assistant Professor of
Pharmacology.

AGskb