Mismatches during DNA replication are typically resolved by which mechanism?

Mismatches during DNA replication are primarily resolved by the mismatch repair mechanism. This cellular process is specifically designed to detect and correct errors that occur when DNA is copied. During replication, DNA polymerase can occasionally incorporate the wrong nucleotide, leading to a mismatch. The mismatch repair machinery identifies these errors shortly after replication has taken place.

The components of the mismatch repair system recognize and bind to the mismatched base pairs. Then, the incorrect base is excised, and DNA polymerase synthesizes the correct nucleotide using the complementary strand as a template. This precise correction is crucial for maintaining the integrity of the genetic information, preventing mutations that could arise from uncorrected mismatches.

The other mechanisms mentioned—double-strand break repair, nucleotide excision repair, and base excision repair—address different types of DNA damage and do not specifically target mismatches resulting from replication errors. Double-strand break repair is involved in repairing breaks in both strands of the DNA helix. Nucleotide excision repair deals with bulky DNA adducts and lesions that distort the DNA helix, while base excision repair is focused on correcting small, non-helix-distorting base lesions. Hence, the unique function of mismatch repair makes it the correct answer for addressing