INDIAN STATISTICAL INSTITUTE

Telegram :  STATISTICA, CALCUTTA-36
Telephones  56-3222-27 (6 lines)

Dear Crick,

203, RARRACKPORE TRUNK ROAD
              CALCUTTA-35

Xere are a fetv lines to conp3tulate you on your F.R.'S. Ez gives

one a satisf.actory reeling that one can be fairly sure of getting a job if

need be,  and that someone besides old -really thinks ones work has been

good. I shozld be fascinated to knozv T7;ha-t ;"ou are going to do next. &re

everyone thinks they would like to do your sort of work, until I give our

mathematicians the problem. "'riow many amino-acids can you represent with

scqaences of 2 members chosen frornb nucleotides, given that all sequences of

2 beginning at the wrong place are nonsense?" Kuch more

your %odel" , if we define a unit mutation as the substitution o

in a chain , mhat fraction of mutations will give act?>al proteins ? lind That

haspens when you get a nonsense sequence of three ? Does t%s mean the end of
  Q                                                    -e
a peptide chain ? In other words do nonsense mutations break paptide chains ?
If so one can see at once why most mutations entail loss of function.           re

      The work which I am gettin g started here is elementary biology
which might perfectly well have been done by Darwin, but wasn't e 3o~~ever it
is exciting enough, and may give quite fantastic increases In crop yield.
Xobody seems to 'know anythili g about variation of organs i:l the same plant.
In fact S.K.Boy finds that while the mean petal number (for exqlle) ;nay
hardly change in a season, the variance may double. Hov:ever I sudpose this is
                                                                           A
less up your street than the origin of lifeLin Penrose& laboratory.

                                                           il
Dr. FSQ&S HEWEY Cm Cricg, FR(
Mm "1                          Yours sincerely,
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The Cavendish Laboratory,
Cambridge.