The Molecular Basis of Xeroderma Pigmentosum

BACKGROUND: Xeroderma pigmentosum is an extremely rare, autosomal recessive disease characterized by a more than 1000-fold increase in nonmelanoma skin cancer. Individuals with this disease can be divided into eight complementation groups: A-G and V for variant. Each one represents a different genetic defect in DNA repair. OBJECTIVE: To review the molecular basis of xeroderma pigmentosum. RESULTS: Deficiencies in various gene products in the nucleotide excision repair pathway cause xeroderma pigmentosum in complementation groups A-G. The molecular basis of the variant group remains to be elucidated. CONCLUSIONS: Research into the genetic defects underlying xeroderma pigmentosum have led to an increased understanding of nucleotide excision repair.