Thank you so much for the letter and the preprint. I must really congratulate you on the poly A-polylysine result. We are
all kicking ourselves for having missed it. Naturally I am delighted that you are finding more triplets. You will remember
that when I visited you last February I felt sure that there would be many more than the ones you had then. I am still not
very happy about the identification of triplets, and feel that it is important to make polynucleotides with a range of compositions
and not just 5:1 or 1:5.
As to the question of degeneracy I feel that if all the codons are triplets, and if, say AUC, ACC, AGC and AAC all stand for
histidine (we would write this as A-C) nevertheless one would call this degeneracy. You will see that I discuss such possibilities
in my review, including your point about transfer RNA (see pages 62 and 63). On the other hand if Robert's code were
correct, i.e. a mixture of doublets and triplets, one for each amino acid, so that the reading sometimes moved on two steps
and sometimes three, then I would agree that it should be called non-degenerate. However, I feel our genetic results make
such a code unlikely. I wish I could penetrate the logic (if any) of the degeneracy but so far it has baffled me.
Off to Stockholm in a day or so. It will be quite a family affair this time.