A novel nonsense mutation of in a Vietnamese family with xeroderma pigmentosum syndrome group D.

Xeroderma pigmentosum (XP) group D, a severe disease often typified by extreme sun sensitivity, can be caused by mutations. encodes an adenosine triphosphate (ATP)-dependent DNA helicase, namely XP group D protein (XPD). The XPD, one of ten subunits of the transcription factor TFIIH, plays a critical role in the nucleotide-excision repair (NER) pathway. Mutations in XPD that affect the NER pathway can lead to neurological degeneration and skin cancer, which are the most common causes of death in XP patients. Here, we present detailed phenotypic information on a Vietnamese family in which four members were affected by XP with extreme sun sensitivity. Genomic analysis revealed a compound heterozygous mutation of that affected family members and single heterozygous mutations in unaffected family members. We identified a novel, nonsense mutation in one allele of (c.1354C > T, p.Q452X) and a known missense mutation in the other allele (c.2048G > A, p.R683Q). Fibroblasts isolated from the compound heterozygous subject also failed to recover from UV-driven DNA damage, thus recapitulating aspects of XP syndrome in vitro. We describe a novel variant that leads to the breakdown of the NER pathway across generations of a family presenting with severe XP.