. . . . . . . . . . . . "[Many XP patients are compound heterozygotes with a causative XPD point mutation R683W and different second mutant alleles, considered null alleles. However, there is marked clinical heterogeneity (including presence or absence of skin cancers or neurological degeneration) in these XPD/R683W patients, thus suggesting a contribution of the second allele.]. Sentence from MEDLINE/PubMed, a database of the U.S. National Library of Medicine."@en . . . . . "2016-02-19"^^ . . "Gene-disease associations inferred from text-mining the literature."@en . "DisGeNET evidence - LITERATURE"@en . "2016-05-13T12:47:37+02:00"^^ . . . . . . . . . . . "v4.0.0.0" . "v4.0.0" .