If unrepaired, CPD photoproducts can lead to mutations by inaccurate translesion synthesis during DNA replication or repair. The most frequent mutations due to inaccurate synthesis past CPDs are cytosine to thymine (C>T) or CC>TT transition mutations. These are commonly referred to as UV fingerprint mutations, as they are the most specific mutation caused by UV, being frequently found in sun-exposed skin but rarely found in internal organs. Errors in DNA repair of UV photoproducts, or inaccurate synthesis past these photoproducts, can also lead to deletions, insertions and chromosomal translocations.