Roscoe B. Jackson Memorial Laboratory

BAR HARBOR, MAINE

Cable Address
June 20, 1957 “JAXLAB’

Dr.Joshua Lederberg,

Department of Medical Genetics,
Genetics Building, Univ.eof Wisconsin,
Madison 6, Wisconsin.

Dear Josh,

Would that all questions were as pleasant to answer as the one you posed
about isogenic lines differing only in particular color genes! The construction
and utilization of such lines is a business we have gone in for in a very large
way. So far I have found no color gene which is antigenic~— all of these
isogenic lines are absolutely beantiful tools in physiological genetics because
you can so easily make tissue from individuals of one venotype grow in the
body of an individual of different genotype, provided you use the proper isogenic
combination( either within inbred strain or from inbred strain to its F hybrid).
Just for fun I'm sendin- along a few reprints of articles which have debended
upon just such transplantations!

if you are interested in details, we have a long series of coat-—c isogenics
with C57BL/6: A’, a’, c (arose by mtation within inbred strain), Mi, W, WY,
Bo ( all more than 8 backcross generations, some as many as 334) plus pa, Va,
and ru ( in process). There is one standard inbred strain, 129, originally
developed by Dunn, which has always been maintained heterozygous for 6° Ce
This has proven extremly useful as a genetic marker in ovarian transplantations,
since by making appropriate combinations it is always possible to distinguish
offspring from the transplant from offspring of host ovary regenerated. This
has been used for many genetic purposes, the one from which I personally have
benefited from most being a large series of ovarian transplants made by Dr.
Stevens of our laboratory in establishing the exact*nature of inheritance of
mouse muscular dystrophy, and in building up a supply colony of dystrophics °
and known heterozygotes. A paper on this has appeared in the Maygf PSEBIM(Stevedns,
Russell, and Southard, PSEBM 95:161-16, no reprints yet available). We have
a number of other isogenics, including my long-lived WB, WC, WH, WK. In every
case so far tested, tissues have been very histocompatible between the isogenic
types.

Now, sir, that you have become involved with Medical Genetics, wouldn't you
be interested someday in encouraging a bright student to come play with these
beautiful tools? They are really ideal for unravelling sene~action pathways,
and for answering loads of other questions. We'd love to have a number of
Wisconsin pre- and/or postdottoral students working here on fellowships from
our National Cancer Institute Training grant. Jim Crow has heard something
of this story already, and if you really are interested, I'd be glad to discuss
this further with you. Our concept for the pre-doctoral student involves a
joint sponsorship arrangement, with courses and degree from Wisconsin, but
a large part of thesis work carried out here with the mammalian materials and
technical advice we have to offer.

Meanwhile, you really should bring your wife and coma for a visit here
while I'm at home-- didn't you drop in while I was away not too long ago?
We'd all love to have you do so any time you can make it.—-

Sincerely,

Tih?