Department of Genetics, University cf Wisconsin, Madison6é, Wis.

March 12, 1952

Dear Dr, Nobel:

Please pardon my tradiness in answering yours of the 2lst last; I
was away at meetings part of the time and could not find time sooner.

Your photographs, and more important, your confidence in the newfound
zygotes of E. coli were received with the utmost interest. I am most
eager to learn enough about the matter (as you mst be) to see whether
some genetic tests by way of confirmation can be formulated. If you
have managed to control the conditions of zygote occurrence, could you
send us sometime 4) a slide that gives some ides of the disposition of
the materiai, and bj some concrete account of the details of the observa-
tions. ie should like only to be the more antelligently prepered for
your visit when it m:terleiizes.

A years’ ago, I should have thought that the absence of the zygotes
in the perental cultures themselves would have been conclusive evidence
against their significance. More recently, we (this includes Cavalii, at
ittxkx Milan, as well as ourselves: there 4e quite a UN flavor to this)
have been accumleting evidence that these particular cultures are, ina
sense, sexuelly differentiated, and that self—matings occur infrequently,
if at all. I should venturg to predict, however, that if the zygotes are
valid, you will find then in. 58-161, although to o scmewhet lesses extent
than in 58-idi x #-677 or x --i177. The latter two culiures should, ae sy
first guess, mot have them ab all. In a sense, this would be the first
genetic contirmtion.

Following your suggestion, I have qritten to the Rockefeller Foundation.
As they have been supporting the wcrk of this laboratory, I am sure your
application will receive sympathetic consideraticn. There will be time
enough later to consider financial alternatives. Under any circumstanees,
kowever, you would gurls probably have to find sows way of financing your
passage. Have you looked into what we call the "reverse-Fulbright" program?

Of course we shall be most delighted to have yo. spend some time in
our laboratory. As fT may have aentioned, cur space situation hs such as to
recommend soms period about one year from now, rather than earlier in tke
1952-53 academle sear. But by then, perhaps you will have compketely solved
the cytological problem of sex in K-12!

Yours sincerely,

Joshua Lederberg