Genetic polymorphism of cytochrome P4501A1 and susceptibility to oral squamous cell carcinoma and oral precancer lesions associated with smoking/betel use

J Oral Pathol Med. 2002 Oct;31(9):505-11. doi: 10.1034/j.1600-0714.2002.00158.x.


Background: The importance of the CYP1A1 polymorphisms at exon 7 (Ile/Val) and 3'-untranslated region (3'-UTR) has been controversial in oral squamous cell carcinoma (OSCC) or head and neck SCC (HNSCC) denoting the value of exploring the correlation between these polymorphisms and risk of betel/smoking associated OSCC. It is also important to evaluate the association between CYP1A1 polymorphisms and susceptibility of oral precancerous lesion (OPL) to confirm the findings in OSCC cases.

Methods: We examined polymorphic prevalence of CYP1A1 at exon 7 (Ile/Val) and 3'-UTR in 106 cases with OSCC, 60 cases with OPL, and 146 controls. DNA isolated from surgical specimens and whole blood was used for PCR-based genotyping.

Results: The prevalence of the CYP1A1 A/G genotype (Ile/Val) and G/G genotype (Val/Val) in exon 7 of cases with OSCC (79.2 and 7.6%) and OPL (68.3 and 10%) were significantly higher than in controls (53.4 and 1.4%) (P < 0.0001). The novelty of the present study is that we identified the onset age of OSCC in CYP1A1 A/G genotype to be significantly younger than that in A/A genotype (P < 0.01). No significant difference was seen between cases and controls regarding the polymorphisms at 3'-UTR.

Conclusion: The findings indicate that the individuals with the CYP1A1 exon 7 containing G allele were at increased risk for OSCC and OPL.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age of Onset
  • Aged
  • Aged, 80 and over
  • Amino Acid Substitution
  • Areca / adverse effects
  • Carcinoma, Squamous Cell / enzymology
  • Carcinoma, Squamous Cell / etiology
  • Carcinoma, Squamous Cell / genetics*
  • Cytochrome P-450 CYP1A1 / genetics*
  • Exons / genetics
  • Female
  • Genetic Predisposition to Disease / genetics*
  • Humans
  • Male
  • Middle Aged
  • Mouth Neoplasms / enzymology
  • Mouth Neoplasms / etiology
  • Mouth Neoplasms / genetics*
  • Mutation, Missense
  • Polymorphism, Restriction Fragment Length
  • Precancerous Conditions / enzymology
  • Precancerous Conditions / etiology
  • Precancerous Conditions / genetics*
  • Smoking / adverse effects
  • Smoking / genetics
  • Untranslated Regions / genetics
  • Valine / genetics


  • Untranslated Regions
  • Cytochrome P-450 CYP1A1
  • Valine