Codon wobble positions
The wobble position of a codon refers to the 3rd nucleotide in a codon. This nucleotide has two major characteristics:
- Binding of a codon in an mRNA the cognate tRNA is much "looser" in the third position of the codon. This permits several types of non-Watson–Crick base pairing to occur at the third codon position.
- The genetic code is redundant whereby several different codons code for the same amino acid. Often, this redundancy is specified in the third codon position such that several codons with the same first two nucleotides, but different third position nucleotides, code for the same amino acids.