Identification of splicing mutations of the last nucleotides of exons, a nonsense mutation, and a missense mutation of the XPAC gene as causes of group A xeroderma pigmentosum

Mutat Res. 1992 Mar;273(2):203-12. doi: 10.1016/0921-8777(92)90081-d.


Four mutations of the XPAC gene were identified as molecular bases of different UV-sensitive subgroups of xeroderma pigmentosum (XP) group A. One was a G to C transversion at the last nucleotide of exon 4 in GM1630/GM2062, a little less hypersensitive subgroup than the most sensitive XP2OS/XP12RO. The second mutation was a G to A transition at the last nucleotide of exon 3 in GM2033/GM2090, an intermediate subgroup. Both mutations caused almost complete inactivation of the canonical 5' splice donor site and aberrant RNA splicing. The third mutation was a nucleotide transition altering the Arg-211 codon (CGA) to a nonsense codon (TGA) in another allele of GM2062. The fourth mutation was a nucleotide transversion altering the His-244 codon (CAT) to an Arg codon (CGT) in XP8LO, an intermediate subgroup. Our results strongly suggest that the clinical heterogeneity in XP-A is due to different mutations in the XPAC gene.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Base Sequence
  • Blotting, Northern
  • Cell Line
  • DNA / radiation effects
  • DNA Mutational Analysis
  • DNA Repair / genetics
  • Exons*
  • Humans
  • Molecular Sequence Data
  • Mutation*
  • Polymerase Chain Reaction
  • RNA Splicing / genetics*
  • Ultraviolet Rays
  • Xeroderma Pigmentosum / genetics*


  • DNA