SEP 17 1971

Yale Univer sity New Haven, Connecticut 06510

DEPARTMENT OF MICROBIOLOGY
310 Cedar Street

Telephone. (203) 436-1770
September 15, 1971

Dr. Joshua Lederberg

Department of Genetics

Stanford University School of Medicine
Stanford, California 94305

Dear Josh:

I am writing to inquire about the possibility of my coming to your lab this month
to work on strain pedigrees again. I would like to set out next week for Denver,
where I shall take Larry Morse's Ki2 strains off his hands and work out pedigrees
for them while I am there. Then I would like to come to Palo Alto, say on
September 27, if that is not inconvenient for you, to work with your strain records
as I did before. I shall endeavor to explain below what I have in mind concerning
the strain pedigrees.

The Coli Genetic Stock Center has evolved by now into a much larger operation than
we initially had in mind. The NSF (i.e., Herman Lewis and the Genetics Society of
America's Committee on the Maintenance of Genetic Stocks, which advises the NSF

on these matters) now quite clearly regard us as being responsible for setting up

a comprehensive collection of K12 stocks that will constitute the major central
repository for research strains. At the insistence of Herman Lewis and the
Committee members, the existence of the Stock Center is being announced this fall in
Nature, Science, the ASM News and the Microbial Genetics Bulletin. This will un-
doubtedly lead very shortly to a great increase in the number of strain requests

and means also that we should accelerate the process of taking in strains from other
labs. The limiting factor here is the working out of pedigrees.

If one accepts the conclusion that it is worthwhile to assemble and maintain such a
collection, then I think one has to conclude also that it is worthwhile working out
strain pedigrees in order to keep track of the mutant alleles in the collection.
This is what I am trying to do as we take strains in. Apparently, this is of some
real value, as I get many requests concerning the ancestry of our strains and the
feedback has indicated that people would like to see some of this information
published, somewhere.

Herman Lewis has been very keen on our publishing a Stock List in some form or other.
I have opposed this idea on the grounds that such a list, if it contained complete
strain descriptions, would be too cumbersome to be of any use to anyone without

our computer and/or record books. However, I think I have devised a format that
would make such a list usable and we are now considering how to present it.

One possibility that is being considered is a supplement to the Microbial Genetics
Bulletin devoted to the Stock Center which would be sent out to the MGB mailing list
and printed in great excess so that copies could be obtained by others on request.

This would contain, possibly, a Stock List, Pedigree Charts, Hfr and F' Maps

(prepared by Brooks Low; showing points of origin and the extent of F's) and possibly
miscellaneous gleanings such as lists of synonymous strain numbers, etc. The index

to all of this would be something of an undertaking, too. It is possible that we would
try to get this material assembled by next Spring.
Dr. Joshua Lederberg
Page 2

As far as the pedigrees are concerned: there is no point in presenting pedigree
charts unless they are done much more carefully than these things have been done in
the past. For example, I have finally worked out the derivation of HfrH (enclosed)
and gotten Hayes' verification of it. It is a great deal more complicated than the
version that is usually presented. I've also, I think, cleared up some of the
confusion as to the derivation of CR34 (enclosed) which a number of people have
inquired about. Appleyard has verified this.

Only recently I concluded that the strain that Ed Adelberg had always thought was

the Hfr Cavalli (his AB257) is not, in fact, the Hfr Cavalli but is instead the Hfr
type 3 isolated as a spontaneous mutant from "58-161" (W6) by Jacob and Wollman in
their early papers. It was brought here by Pardee and was called strain 4000 and

was described as being a "Cavalli-type" Hfr but carelessness somewhere along the

line led to its being described as the Cavalli Hfr. The point of origin is apparently
very similar, if not identical, but it should be given a different designation. I've
written to Elie Wollman to see if he can verify this for me. So I shall have to

track this through the various collections now and make corrections accordingly.

The supE mutation that keeps cropping up in various strains descended from Y10
was once demonstrated in Y10, I now know, and the question is when it first appeared.
I am hoping to persuade someone to check on this in the laboratory.

If this sort of information is of general value then I guess it ought to be presented
and I ought to continue gathering it. This means that I am pestering a great many
people, including yourself, and it also means that I shall have to go to Paris soon
because I can't figure out the Paris strains from reading the literature and I can't
seem to get any information from the Paris lab by mail.

If something like the MGB supplement does come to pass, I would like to include pedigrees
of some of the major lines of your Wisconsin strains. I think I got a number of them
straightened out the last time I visited your lab. This time I want to check them
carefully and also to put in references to the literature, where possible, for the
various steps. Some of these are enclosed.

I gather that you would not want this material presented without your checking it,
and yet this would require more time and effort than you would be likely to want to
devote to the task. I don't quite see a way around this dilemma at the moment.
Whether the pedigrees are 'published' or not, I shall have to continue constructing
them in order to keep our allele numbers straight. But the assignment of allele
numbers on the basis of pedigrees that I work out amounts, in a sense, to my publish-
ing (or publicizing) the pedigrees. I would like to talk to you to see if we can
sort out the responsibility for all of this to our mutual satisfaction.

Since I am writing on such short notice, I shall call you before leaving New Haven

if I haven't heard from you by then. It would be very helpful to have access to your
strain cards and book again. Also, if you have a list of your publications or a file
of your reprints that would be very helpful, too. This is going to continue for

some years, I'm afraid, as we are continually acquiting new strains and tracing them
back to Wisconsin strains that we weren't concerned with before.
Dr. Joshua Lederberg
Page 3

I am certainly not averse to making an annual trip to Stanford. I hope that it is
not too much of a bother to you.

Sincerely,
TB tan

Barbara J. Bachmann
bjb/nj