This G-T mismatch repair mechanism occurs in addition to a more general system that repairs virtually all mismatches. Suggest a reason why cells might require a specialized system to repair G-T mismatches in this way. (5 pts)

The given question is incomplete, the complete question is:

A particular type of DNA damage involves purely chemical (non-enzymatic) degradation steps, like deamination, or depurination. Due to these, and other forms of DNA damage, cells employ a range of DNA repair mechanisms in order to maintain the integrity of the genetic code over millions of generations. Many eukaryotic cells have a specialized repair mechanism for the repair of G-T mismatches. This mismatch is repaired to form G=C (not A=T) base pair. This G-T mismatch repair mechanism occurs in addition to a more general system that repairs virtually all mismatches. Suggest a reason why cells might require a specialized system to repair G-T mismatches in this way.

The repair of G-T mismatch is performed through the process called very short patch repair. The mismatch takes place because of the deamination of 5-methyl cytosine into thymine that occurs due to DNA mutation. The process of repair is performed with VSR endonuclease that eradicates the thymine on 5 prime end and then resynthesis of the patch is done with the assistance of DNA polymerase.

In case, if the repair does not take place it can result in transition mutation, that is, a kind of point mutation. As this repair is required to be very accurate, thus, the special VSR endonuclease is used for very short patch repair.