Smoking but not homozygosity for CYP1A2 g-163A allelic variant leads to earlier disease onset in patients with sporadic porphyria cutanea tarda

Antonio Fontanellas*, Maria Martinez-Fresno, Maria Concepcion Garrido-Astray, Teresa Perucho, Maria-Josefa Moran-Jimenez, Maria Garcia-Bravo, Manuel Mendez, Pamela Poblete-Gutierrez, Jorge Frank, Nuno Henriques-Gil, Rafael Enriquez de Salamanca

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

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Porphyria cutanea tarda (PCT) results from decreased activity of hepatic uroporphyrinogen decarboxylase (UROD). Both sporadic and familial forms are characterised by typical cutaneous lesions triggered by genetic/environmental factors. Studies in rodents showed that cytochrome P4501A2 (CYP1A2) plays a central role in the synthesis of a competitive inhibitor of hepatic UROD, but there is little evidence in humans. The impact of smoking and CYP1A2 g-163C > A allelic variant upon first appearance of clinical signs was investigated in 102 patients (80 sporadic-PCT) and 150 healthy donors from Spain. We found an increase in the frequency of CYP1A2 g-163A allele in patients with PCT when compared with controls, although the more inducible A/A genotype had no effect on the onset age. In sporadic-PCT, smoking leads to earlier onset of clinically overt disease in moderate-to-heavy smokers (>= 10 cigarettes/day). In conclusion, this study provides evidence that smoking hastens the onset of cutaneous symptoms in sporadic-PCT patients.
Original languageEnglish
Pages (from-to)E326-E328
JournalExperimental Dermatology
Issue number8
Publication statusPublished - Aug 2010


  • cytochrome P4501A2 allelic variant
  • onset of cutaneous symptoms
  • porphyria
  • tobacco smoke
  • uroporphyrinogen decarboxylase

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