Development and inter-laboratory validation of unlabeled probe melting curve analysis for detection of JAK2 V617F mutation in polycythemia vera.
BACKGROUND
JAK2 V617F, a somatic point mutation that leads to constitutive JAK2 phosphorylation and kinase activation, has been incorporated into the WHO classification and diagnostic criteria of myeloid neoplasms. Although various approaches such as restriction fragment length polymorphism, amplification refractory mutation system and real-time PCR have been developed for its detection, a generic rapid closed-tube method, which can be utilized on routine genetic testing instruments with stability and cost-efficiency, has not been described.


RESULTS
Asymmetric PCR for detection of JAK2 V617F with a 3'-blocked unlabeled probe, saturate dye and subsequent melting curve analysis was performed on a Rotor-Gene® Q real-time cycler to establish the methodology. We compared this method to the existing amplification refractory mutation systems and direct sequencing. Hereafter, the broad applicability of this unlabeled probe melting method was also validated on three diverse real-time systems (Roche LightCycler® 480, Applied Biosystems ABI® 7500 and Eppendorf Mastercycler® ep realplex) in two different laboratories. The unlabeled probe melting analysis could genotype JAK2 V617F mutation explicitly with a 3% mutation load detecting sensitivity. At level of 5% mutation load, the intra- and inter-assay CVs of probe-DNA heteroduplex (mutation/wild type) covered 3.14%/3.55% and 1.72%/1.29% respectively. The method could equally discriminate mutant from wild type samples on the other three real-time instruments.


CONCLUSIONS
With a high detecting sensitivity, unlabeled probe melting curve analysis is more applicable to disclose JAK2 V617F mutation than conventional methodologies. Verified with the favorable inter- and intra-assay reproducibility, unlabeled probe melting analysis provided a generic mutation detecting alternative for real-time instruments.
Department of Laboratory Medicine, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China.
Zhiyuan
Z
Wu
Hong
H
Yuan
Xinju
X
Zhang
Weiwei
W
Liu
Jinhua
J
Xu
Wei
W
Zhang
Ming
M
Guan
D045744:Cell Line, Tumor; D004252:DNA Mutational Analysis / Q000295:instrumentation / Q000379:methods*; D015342:DNA Probes / Q000737:chemistry* / Q000235:genetics; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics*; D007753:Laboratories; D020125:Mutation, Missense / Q000235:genetics*; D021141:Nucleic Acid Amplification Techniques; D009691:Nucleic Acid Denaturation; D011087:Polycythemia Vera / Q000201:enzymology / Q000235:genetics*; D044366:Transition Temperature
D015342:DNA Probes; D053614:Janus Kinase 2