title: [Mutation and polymorphism of the ameloblastin gene in ameloblastomas].
abstract: OBJECTIVE
  To investigate the presence of mutation or polymorphism of ameloblastin (AMBN) gene in ameloblastomas.
  
  
  METHODS
  Genomic DNA was extracted from frozen tissues of 10 ameloblastomas and one malignant ameloblastoma. AMBN gene alterations were detected by PCR-direct sequencing. Restriction fragment length polymorphism (RFLP) analysis was used to further determine the nature of the changes in AMBN detected in tumor samples in comparison to 100 control samples.
  
  
  RESULTS
  AMBN mutation was not identified in all 11 tumor samples. The 7 types of AMBN gene alteration identified in 9 cases were proven to be polymorphisms, three of which were not previously reported. The frequency of genotype and allele of the three SNPs complied with the Hardy-Weinberg equilibrium. Neither genotype nor allele frequency showed a significant association with ameloblastoms.
  
  
  CONCLUSIONS
  AMBN gene mutation is not identified in the present group of ameloblastomas. The frequently detected AMBN alterations in ameloblastomas are polymorphisms, which appear to be unrelated to the occurrence of ameloblastomas.
authors.affiliation: Department of Oral Pathology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Chun-hua
authors.initials: CH
authors.lastname: Niu
authors.forename: Tie-jun
authors.initials: TJ
authors.lastname: Li
mesh_terms: D000293:Adolescent; D000328:Adult; D000564:Ameloblastoma / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D003746:Dental Enamel Proteins / Q000235:genetics*; D006801:Humans; D007573:Jaw Neoplasms / Q000235:genetics*; D008875:Middle Aged; D009154:Mutation; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA; D055815:Young Adult
chemical_list: C490889:AMBN protein, human; D003746:Dental Enamel Proteins