During DNA replication, several natural proofreading mechanisms are in place to prevent an error from occurring. However, errors can occur occasionally. If the error is not fixed, it becomes a genetic mutation.

How can a mutation affect protein synthesis by a cell? Do you think there are different consequences if it happens in a gamete cell (sperm or egg) versus a non-gamete cell?

Answer: Genes are responsible for coding proteins, which are needed for all of our body functions and to build our body structures. So, a mutation could affect the way a protein is made. If the error occurs in the gamete cell, it could lead to a mutation in a growing fetus. Because all cells in the body form from two fertilized gametes, this mutation may exist in all the cells of the developing baby. If it occurs in another cell, a skin cell, for example, then the mutation would be confined to the cells in the skin tone.