. . . . . . . . . . . . "[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 . . . . . "2014-02-25"^^ . . "Gene-disease associations inferred from text-mining the literature."@en . "DisGeNET evidence - LITERATURE"@en . "2014-10-02T12:38:11+02:00"^^ . . . . . . . . . . . "v2.1.0.0" . "v2.1.0" .