Final answer:
A mutation in mRNA can cause the production of defective proteins or no protein at all. Changes in the mRNA sequence can lead to the incorporation of incorrect amino acids or the introduction of premature stop codons, affecting the structure and function of the protein.
Step-by-step explanation:
A mutation in mRNA can have various effects on the production of proteins. Firstly, if there is a mutation in the mRNA sequence, it can result in the production of defective proteins. This occurs when the mutation changes the codon in the mRNA, leading to an incorrect amino acid being incorporated into the growing protein chain. As a result, the structure and function of the protein may be altered.
Additionally, the mutation in mRNA can also lead to the production of no protein at all. If the mutation introduces a premature stop codon, it causes the ribosome to stop protein synthesis prematurely, resulting in a truncated and non-functional protein.