Errors during transcription don't always lead to incorrect amino acid sequences during translation because of the redundancy of the genetic code. The genetic code is degenerate, meaning that multiple codons can code for the same amino acid. Here are two examples to illustrate this:
1. Silent Mutation: A mutation in the DNA sequence that doesn't change the amino acid produced during translation is called a silent mutation. For instance, if the original codon was GCU (coding for alanine), and due to an error in transcription, it changes to GCA, which still codes for alanine. This type of mutation does not affect the final protein product.
2. Missense Mutation: In contrast, a missense mutation results in a change in the amino acid sequence. However, not all missense mutations lead to a non-functional protein. For example, if the original codon was UUA (coding for leucine) and due to an error, it changes to UCA (coding for serine), the resulting protein may still function properly if the new amino acid can fulfill a similar role in the protein structure or function.
These examples demonstrate that errors during transcription may not always result in incorrect amino acid sequences during translation due to the redundancy and flexibility of the genetic code.
