Korean J Hematol.  2009 Jun;44(2):100-103. 10.5045/kjh.2009.44.2.100.

Mutation of the N-ras Gene in a Patient Suffering from the Blast Phase of Chronic Myelogenous Leukemia

• Song SH
• Roh YW
• Ahn YW
• Kim YJ
• Byoun YS
• Choi JY
• Hwang DW
• Park BB
• Choi JH
• Kim IS
• Kim BK
• Lee YY

• KMID: 2252154
• DOI: http://doi.org/10.5045/kjh.2009.44.2.100

Abstract

The blast phase in chronic myelogenous leukemia (CML) is associated with mutation of several genes. It is well known that p53 gene mutation plays a key role in the myeloid or lymphoid blast phase of CML. But for the case of the N-ras gene, the association between N-ras mutations and the blast phase of CML is not yet known. We report here on a case of detecting N-ras point mutation without p53 mutation in a 64 year-old man who suffered from the lymphoblastic blast phase of CML.

Keyword

Chronic myelogenous leukemia; Gene mutation; Blast phase; N-ras

MeSH Terms

Blast Crisis
Genes, p53
Genes, ras
Humans
Leukemia, Myelogenous, Chronic, BCR-ABL Positive
Point Mutation
Stress, Psychological

Figure

• 

  Fig. 1. PCR-SSCP analysis of N-ras exon 1 in a patient with CML-blast phase. Band shift due to point mutation was detected on the arrowed sample. Controls included DNAs from a sample with known N-ras exon 1 mutation as a positive control (P), from normal lymphocytes as a normal control (W), and a negative control (no template DNA) (N).

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  Fig. 2. Dinucleotide sequencing of exon 1 of N-ras gene from DNA of a patient with CML-blast phase. Sequences are shown 5' (top) to 3' (bottom). A codon 13, GGT, was mutated to CGT, substituting an aminoacid arginine for glycine. Arrow indicates the base that has the point mutation.

• 

  Fig. 3. PCR-SSCP analysis of p53 gene of exon 5 (A), 6 (B), 7 (C), and 8 (D) in a patient with CML-blast phase. No band shift was observed in the patient (P).

Reference

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