Description:
<jats:p><jats:bold>Background: </jats:bold> Previous studies of oral carcinomas have shown that both loss of heterozygosity (LOH) and hypermethylation at chromosome 9q33 to 9q34.2 are frequent. The present study investigates the frequency of <jats:italic>Notch1</jats:italic> gene methylation and LOH at 9q34.3 region.</jats:p><jats:p><jats:bold>Methods: </jats:bold> Gene promoter hypermethylation of the <jats:italic>Notch1</jats:italic> gene was analysed by methylation‐specific PCR and LOH was analysed using microsatellite markers.</jats:p><jats:p><jats:bold>Results: </jats:bold> We found LOH at 9q34.3 in three patients and methylation of the <jats:italic>Notch1</jats:italic> gene only in two patients with oral carcinoma.</jats:p><jats:p><jats:bold>Conclusion: </jats:bold> Comparing with the alterations at 9q33 to 34.2 regions, LOH at 9q34.3 and methylation of the <jats:italic>Notch1</jats:italic> gene was less involved in oral squamous cell carcinomas.</jats:p>