Table 1.
The XP genes
| Gene | No of exons | Chromosomal locationa | Protein size (aa) | Protein function | Defective pathway |
|---|---|---|---|---|---|
| XPA | 6 | 9q22.33 | 273 | Damage verification | NER |
| XPB/ERCC3 | 15 | 2q14.3 | 782 | Helicase | NER |
| XPC | 16 | 3p25.1 | 940 | Damage recognition | NER (GGR) |
| XPD/ERCC2 | 23 | 19q13.32 | 760 | Helicase | NER |
| XPE/DDB2 | 10 | 11p11.2 | 427 | Damage recognition | NER (GGR) |
| XPF/ERCC4 | 11 | 16p13.12 | 916 | Nuclease | NER |
| XPG/ERCC5 | 15 | 13q33.1 | 1186 | Nuclease | NER |
| XPV/POLH | 11 | 6p21.1 | 713 | Polymerase | TLS |
Abbreviations. NER: Nucleotide excision repair; GGR: global genome repair sub-pathway; TLS: translesion synthesis.
a From [23].