title: A point mutation at codon 13 of the N-ras oncogene in myelodysplastic syndrome.
abstract: Patients with a myelodysplastic syndrome (MDS) which has a risk of leukaemic change exhibit a variable clinical course. It has been suggested that the development of leukaemia in patients with MDS may be related to chromosomal abnormalities or genetic alterations: somatic mutation of the N-ras gene is now considered to be a critical step in the genetic basis of human leukaemogenesis. Here we report that DNAs of bone-marrow cells from three out of eight patients with MDS contained an activated N-ras oncogene, as detected by an in vivo selection assay in nude mice with transfected NIH 3T3 cells. Molecular analysis revealed the same single nucleotide substitution at codon 13 in all three transforming N-ras genes. Each of the three patients showed a progression of the disease and a resulting leukaemic change within the following year. Our observation of the mutation at codon 13 in leukaemic cell DNAs from all three cases suggests that activation of the N-ras gene is important in the development of leukaemia in some MDS cases.
authors.forename: H
authors.initials: H
authors.lastname: Hirai
authors.forename: Y
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Mano
authors.forename: K
authors.initials: K
authors.lastname: Hagiwara
authors.forename: Y
authors.initials: Y
authors.lastname: Maru
authors.forename: M
authors.initials: M
authors.lastname: Omine
authors.forename: H
authors.initials: H
authors.lastname: Mizoguchi
authors.forename: J
authors.initials: J
authors.lastname: Nishida
authors.forename: F
authors.initials: F
authors.lastname: Takaku
mesh_terms: D000595:Amino Acid Sequence; D000753:Anemia, Refractory / Q000235:genetics; D001483:Base Sequence; D001853:Bone Marrow / Q000473:pathology; D002471:Cell Transformation, Neoplastic; D003062:Codon; D006801:Humans; D009154:Mutation; D009190:Myelodysplastic Syndromes / Q000235:genetics*; D009693:Nucleic Acid Hybridization; D009857:Oncogenes; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras)
chemical_list: D003062:Codon; D011518:Proto-Oncogene Proteins; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)