Codons matter

DNA codes for amino acids with triplets of bases (codons). There are four different bases and hence 64 different triplets. There are typically twenty different amino acids (plus start and stop signals) which need to be coded, so there is some redundancy - a single amino acid can have multiple codons which are all translated the same way. However, there is now evidence that the actual codon may make a difference. New Roles for Codon Usage in Science reports that two very similar but distinct proteins are modified differently, depending on the original codon.