Lona IsLAND BIOLOGICAL ASSOCIATION
COLD SPRING HARBOR, NEW YORK

BIOLOGICAL LABORATORY

April 13, 1956
Dr. Joshua Lederberg
Department of Genetics
University of Wisconsin
Madison, Wisconsin

Dear Josh,

I am sorry that I did not send you a copy of the final manuscript of the
mutability paper sooner; I enclose one now. It is scheduled to appear in May.
Most of your suggestions were taken, I believe. I realize that you didn't
suggest the term "binary" for the title; I anticipate disapproval.

Camp Detrick apparently stock-piles reprints of papers with which they are
connected and is willing to fill requests in this country. Therefore, I only
ordered 150 directly, of which I will send you 100. You needn't pay for these.

I am also sending a copy of the paper dealing with the genetic part of the
experiments done with Garen. This has been submitted for clearance but not for
publication, so that changes are still possible. In fact, some of the points are
still not settled between Atan and me. Je will appreciate any suggestions you may
have to make.

I hope that the statements about partial transfer are not too incautious.
I realize that the "spontaneous" egconjugants referrred to may in fact be
"induced" by the sampling technique. This would be critical to several interpretations
that might be made, but not, I think, to the modest one attempted.
s :

In regard to your questions about Pl: I have not worked with K-12 transductions
enough to venture an opinion on them. We have had trouble obtaining high-titered
preparations on B/r, but fortunately transduction frequency seems fairly high.

Four different groups of tryptophane mutations (diff. blocks) seem to be linked
(oy outcrosses to K-12 and by transductions within B/r) as in 3almonella. We

have some information on order, but this is harder to obtain than expected, due to
rarity of all classes but the phage donor type. This suggests that pieced
transferred are larger than in 5almonella (as Lennox also implies).

I plan to go to Bloomington to take part in the symposia which accompany
dedication of the new Bio Bldg. These are June 6-9, so I will probably miss all
or most of the CSH symposium. If you and Esther plan to come here, you are welcome
to the use of our house. Apparently Jacob and Hayes plan to be here and to say
something.

Sincerely,