A range of proteins involved in DNA repair. The rad proteins in yeast were originally identified as products of genes that were very sensitive to X-irradiation and were involved in mitotic and meiotic recombination and mating-type switching. Subsequently human homologues of many of these proteins have been identified. The homologues of yeast RAD23, HHR23A and -B, interact with the product of the xeroderma pigmentosum gene to form a nucleotide excision repair complex. Rad51 (339 aa) is involved (together with the product of a related gene, dmc1) in the repair of double-strand breaks. Mutations to RAD51 modify susceptibility to breast carcinoma. Various others are known, and defects in DNA repair systems are usually associated with tumour susceptibility. See RAD21.
Subjects: Medicine and health