Uracil-DNA glycosylase(UNG)belongs to the uracil-DNA glycosylase family. The human gene encodes one of several uracil-DNA glycosylases. One important function of uracil-DNA glycosylases is to prevent mutagenesis by eliminating uracil from DNA molecules by cleaving the N-glycosylic bond and initiating the base-excision repair (BER) pathway. Uracil bases occur from cytosine deamination or misincorporation of dUMP residues. After a mutation occurs, the mutagenic threat of uracil propagates through any subsequent DNA replication steps. Once unzipped, mismatched guanine and uracil pairs are separated, and DNA polymerase inserts complementary bases to form a guanine-cytosine (GC) pair in one daughter strand and an adenine-uracil (AU) pair in the other.Half of all progeny DNA derived from the mutated template inherit a shift from GC to AU at the mutation site.UDG excises uracil in both AU and GU pairs to prevent propagation of the base mismatch to downstream transcription and translation processes. Synonyms: Uracil-DNA glycosylase,UDG,