Codons are redundant, meaning that several different codon combinations can encode the same amino acid. For example, the amino acid leucine can be specified by codons CUU, CUC, CUA, and CUG. This redundancy, known as the “wobble hypothesis,” is a safety net that reduces the impact of mutations. If a mutation occurs in the third position of a codon, it often doesn’t alter the protein, thus helping to maintain cellular function.
Codon Redundancy: The Genetic Backup System
