It has yet to be shown by direct biochemical methods, as opposed to the indirect genetic evidence mentioned earlier, that the code is indeed a triplet code. Francis Crick biochemicalcodedirect Change image and share on social
Attempts have been made from a study of the changes produced by mutation to obtain the relative order of the bases within various triplets, but my own view is that these are premature until there is more extensive and more reliable data on the composition of the triplets. Francis Crick attemptbasiscomposition share on social
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. Francis Crick acidaminocode Change image and share on social
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. Francis Crick basecodonfairly Change image and share on social
For simplicity one can think of the + class as having one extra base at some point or other in the genetic message and the - class as having one too few. Francis Crick baseclassextra Change image and share on social
If the code does indeed have some logical foundation then it is legitimate to consider all the evidence, both good and bad, in any attempt to deduce it. Francis Crick attemptbadcode Change image and share on social
This seems highly likely, especially as it has been shown that in several systems mutations affecting the same amino acid are extremely near together on the genetic map. Francis Crick acidaffectamino Change image and share on social
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. Francis Crick acidaminobasis share on social
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. Francis Crick acidalterationamino Change image and share on social
