title: Multiple changes in oncogenes and tumor suppressor genes in human retinoblastoma.
abstract: OBJECTIVE
  To present data to support the hypothesis that human retinoblastoma tumors form by a multistep process.
  
  
  METHODS
  Survey of the karyotype of 90 human retinoblastomas, with emphasis on changes in chromosomal regions known to contain oncogenes and tumor suppressor genes.
  
  
  CONCLUSIONS
  The data support the hypothesis that retinoblastoma occurs after multiple and often varied steps, similar to other human malignancies.
authors.affiliation: Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, Connecticut, USA.
authors.forename: R O
authors.initials: RO
authors.lastname: Howard
mesh_terms: D002871:Chromosome Banding; D002874:Chromosome Mapping; D005134:Eye Neoplasms / Q000209:etiology / Q000235:genetics*; D018628:Gene Dosage; D016147:Genes, Tumor Suppressor / Q000235:genetics*; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D007621:Karyotyping; D012175:Retinoblastoma / Q000209:etiology / Q000235:genetics*