Mismatch Repair

Dna polymerase copies both strand of DNA the top strand and bottom strand, sometimes these stands are called Watson and crick strand. But these strands are not perfect, Normally A opposite to T and G opposite to C.Sometimes these make mistakes in copies wrong nucleotide for example T is copied For G where C should be copied potential mutation fortunately cells have repair system that can erase the mutations and those repair protein are called PMS2, MLH1, MSH2, MSH6, these enzyme recruit another enzyme called EX01 (exonulcease), which choppes off the mutant strand and allows dna polymerase to synthesis the correct strand and there by fixing out DNA