A final proof of our ideas can only be obtained by detailed studies on the alterations produced in the amino acid sequence of a protein by mutations of the type discussed here.
quote by Francis Crick
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Unfortunately it makes the unambiguous determination of triplets by these methods much more difficult than would be the case if there were only one triplet for each amino acid.
quote by Francis Crick
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It now seems very likely that many of the 64 triplets, possibly most of them, may code one amino acid or another, and that in general several distinct triplets may code one amino acid.
quote by Francis Crick
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Do codons overlap? In other words, as we read along the genetic message do we find a base which is a member of two or more codons? It now seems fairly certain that codons do not overlap.
quote by Francis Crick
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It seems likely that most if not all the genetic information in any organism is carried by nucleic acid - usually by DNA, although certain small viruses use RNA as their genetic material.
quote by Francis Crick
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The balance of evidence both from the cell-free system and from the study of mutation, suggests that this does not occur at random, and that triplets coding the same amino acid may well be rather similar.
quote by Francis Crick
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It would appear that the number of nonsense triplets is rather low, since we only occasionally come across them. However this conclusion is less secure than our other deductions about the general nature of the genetic code.
quote by Francis Crick
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If, for example, all the codons are triplets, then in addition to the correct reading of the message, there are two incorrect readings which we shall obtain if we do not start the grouping into sets of three at the right place.
quote by Francis Crick
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The meaning of this observation is unclear, but it raises the unfortunate possibility of ambiguous triplets; that is, triplets which may code more than one amino acid. However one would certainly expect such triplets to be in a minority.
quote by Francis Crick
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It is one of the more striking generalizations of biochemistry - which surprisingly is hardly ever mentioned in the biochemical textbooks - that the twenty amino acids and the four bases, are, with minor reservations, the same throughout Nature.
quote by Francis Crick
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