August 26, 1976

Dr. RichardYoung-
Planetary Programs
Office of Space Science
National Aerouautics and Space Administration
Washington, D.C. 20&46

Dear Dick,

  I may have a chance to talk to you about this personally, but I did
not want to take a chance of the thought evaporating while I have
a chance to get it down.

   Every ten years or o o I have had the thought again that we should
try to put some experimental effort here to finding the missing
evolutionary links %u the origin of life on earth, in parallel with
what we are all doing about trying to resynthesize them The big gap L&U&
can be expressed in various ways - there was a little hint of that in
prg addendum to you about the code - concerns organisms that must have
adsted at one the having a less cmspleta development of the code,
the amino acid ensemble, the pattern of DNA to RNA to protein. It is,
of course, comrelvable that every vccatlge of them has disappeared but
that is a point on which there can hardly be explicit evidence and the
matter is perhaps in some sense in the sams state as was the question
of bacterial sexuality in 1945. Until we can find good selective
procedurea and are well informed about what to look for, how can we
be rrure?                                          s

  It occurs to em this would be a good time to renew such an effort.
The last time I got barely Irtarted, I found that my former graduate
student, Norton Zinder, had scooped me on exactly the direction I was
eeeklag: namely with the discovery of RNA phages. So, that even if such a
project does not work out, It may have unsxpected payoff anyhow.

  One thing that occurred to me was whether you might (1) have any ideas
or information yourself that we ought to have in mind In fleshing out this
program. I assume that we would have the greatest success in looking at
unfamiliar envir onments that are not already swamped with the kinds of
organisms already familiar to us , and (2) whether you hsve any inclination
to taking a direct part In such work for some period of time. I do not know
whether there is any prospect 4 your taking a sabbatical or some other
arrangement, but I did want to offer you the possibility of 6 months or
a year or whatever interval like that would suit you to get your hands
dirty In the laboratory again. Since we do not really yet know what we want
to do, I think the demands are far more for uninhibited but self-critical

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Dr. Richard Young                -2-             8/26/76

thinking rather than for speciellted laboratory technique that would
intimldete efther of us if I were in your shoe6 at the present time.

  Anyhow, I just wanted to introduce the general topic and hope we
might have some other opportunities to diecues it in the near future.

Sincerely youra4,

Joshua Lederbarg
Profecrsor of Genetics