Specimen Collection
Note:
All samples should be forwarded to LabPlus at room temperature within 24hours.
4 mL CPD Blood (Preferred)
4 mL CPD Bone Marrow (Preferred)
4 mL EDTA Blood
4 mL EDTA Bone Marrow
Turnaround Time: Within 2 weeks, 4 days
Diagnostic Use and Interpretation
This test detects insertion/deletion mutations in exon 12 of the NPM1 gene. 45% of AML patients have a normal karyotype and of these approximately 60% will have a mutation within the NPM1 gene. These patients may also have a FLT3 mutation and so testing for FLT3 and NPM1 in tandem is recommended. Those patients who DO NOT have a FLT3 mutation but DO have a NPM1 mutation are more likely to have a good response toward treatment.
References:
R G W Verhaak et al., Blood, 2005, 106 (12): 3747.
See also:
FLT3 Mutation Analysis
Contact Information
To contact the Molecular Haematology team please call:
For more information about the Molecular Haematology service at LabPLUS:
Molecular Haematology information page
Information on NPM1gene Mutations:
Mutations within the Nucleophosmin (NPM1) gene have been described in patients with acute myeloid leukaemia (AML). Although chromosomal translocations are common in AML there is a significant group of patients (45%) who have a normal karyotype. Of these patients approximately 60% will have a mutation within the NPM1 gene. Patients may also have a FLT3 mutation and so testing for both FLT3 and NPM1 is recommended. Those patients who do not have a FLT3 mutation but do have a NPM1 mutation have a good response toward treatment and a significantly better overall and disease free survival.
The NPM1 gene mutations described so far all lie with exon 12 and are either insertions of just four bases or insertion/deletions which all result in a frame-shift and elimination of one or both of the c-terminal tryptophan residues. An exon 12 PCR product is produced for each patient and direct sequencing is used to identify the underlying defect.
References:
Falini B. et al. New Eng J Med. 2005;352:254-266.
Thiede C. et al. Blood. 2006;107:4011-4020.
Grisendi S et al. Nat Reviews. 2006;6:493-505.