Background: 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 Notch1 gene methylation and LOH at 9q34.3 region.
Methods: Gene promoter hypermethylation of the Notch1 gene was analysed by methylation-specific PCR and LOH was analysed using microsatellite markers.
Results: We found LOH at 9q34.3 in three patients and methylation of the Notch1 gene only in two patients with oral carcinoma.
Conclusion: Comparing with the alterations at 9q33 to 34.2 regions, LOH at 9q34.3 and methylation of the Notch1 gene was less involved in oral squamous cell carcinomas.