Somatic mutation of the V617F JAK2 gene in patients of the cardiovascular diseases

The JAK2 V617F somatic mutation is one of the most frequent markers of CHIP (clonal hematopoiesis of indeterminate potential). CHIP is characterized by the presence of a myeloid cells clone in peripheral blood in the absence of the sufficient reasons to diagnose the hematologic disease. The CHIP is proposed as a potential independent risk factor for vascular pathology. The aim of this study is to identify carriers of JAK2 V617F mutation among patients admitted for planned hospitalization at the Federal Center of Cardiovascular Surgery of Krasnoyarsk. Materials and methods. The study included 930 venous blood samples. JAK2 V617F mutation was detected by using the allele - specific real time polymerase chain reaction. Results. JAK2 V617F mutation was detected in 15 (1.6%) patients, but only two of them had blood cell count that could cause a hematological disease to be suspected. Conclusion. The inclusion of the JAK2 V617F mutation detection in the complex of laboratory tests of the cardiovascular patients can facilitate the timely identification of patients with increased thrombotic risk, as well as the timely diagnosis of myeloproliferative diseases.

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Detection of the JAK2 V617F Mutation by Real Time PCR in Granulocytes and Platelets of ET Patients.

Blood ◽

10.1182/blood.v108.11.4877.4877 ◽

2006 ◽

Vol 108 (11) ◽

pp. 4877-4877

Author(s):

Beatriz Bellosillo ◽

Eva Gimeno ◽

Raquel Longaron ◽

Lourdes Florensa ◽

Antonio Salar ◽

...

Keyword(s):

Real Time ◽

Direct Sequencing ◽

Specific Treatment ◽

Jak2 V617f ◽

Jak2 V617f Mutation ◽

Wild Type ◽

Rt Pcr ◽

Jak2 Mutation ◽

Allele Specific ◽

V617f Mutation

Abstract Introduction. The JAK2 V617F mutation has been detected in 23%–57% of ET patients by direct sequencing or allele-specific (AS) PCR. It remains unknown, however, if the mutation detected in the granulocyte population, may be equally detected in platelets from these patients. Objective. To compare the detection of the JAK2V617F mutation in granulocytes and platelets from ET patients by real time AS RT-PCR. Patients and methods. Platelets and granulocytes from 50 ET patients from a single institution were studied. Patients were diagnosed according to the WHO criteria. At the time when JAK2 mutation was analyzed 16/50 patients were receiving platelet-lowering therapy ± ASA, 14/50 patients only received ASA and 20/50 received no specific treatment. JAK2 mutation was analyzed by real-time AS RT-PCR with probes specific for the mutated and the wild type form. Results. The V617F JAK2 mutation was detected in 18 out of 50 patients in both granulocytes and platelets by real time AS RT-PCR, and was negative in both cell populations in the remaining 32 patients. In the V617F JAK2 positive cases, the mean Ct(V617FJAK2)/Ct(wild type JAK2) ratio was 1.074±0.062 for granulocytes and 1.038±0.039 for platelets (p=0.048). These values corresponded to a 17.79 ±7.4% of mutated population when granulocytes were analyzed, whereas, a significantly higher percentage of mutated population was observed, 23.45±7.78 %, when platelets were analyzed (p=0.032). Conclusions. The results of V617FJAK2 mutation detection by AS RT-PCR were the same in granulocytes and platelets (either positive or negative). The percentage of clonal population detected in ET patients was significantly higher in platelets than in granulocytes.

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Presence of JAK2 V617F Mutation in Peripheral Blood of Blood Donors with Upper-Limit Hematocrit and Platelet Values.

Blood ◽

10.1182/blood.v110.11.2533.2533 ◽

2007 ◽

Vol 110 (11) ◽

pp. 2533-2533

Author(s):

Paola Bianchi ◽

Elisa Fermo ◽

Fulvio Mozzi ◽

Maurizio Marconi ◽

Alberto Zanella

Keyword(s):

Polycythemia Vera ◽

Blood Donors ◽

Jak2 V617f ◽

Jak2 V617f Mutation ◽

Myeloid Metaplasia ◽

Specific Pcr ◽

Upper Limit ◽

Allele Specific ◽

V617f Mutation ◽

Allele Specific Pcr

Abstract The somatic mutation V617F of JAK2 gene has been identified as a pathogenic factor in typical chronic myeloproliferative diseases (MPDs), in particular polycythemia vera, essential thrombocythemia, and myelofibrosis with myeloid metaplasia. Recently, two studies showed the presence of this mutation also in 37/3935 subjects with non haematological diseases (Xu et al, 2006) and 5/52 healthy donors (Sidon et al, 2006), suggesting that V617F mutation may occur in the absence of MPD phenotype and that probably is not sufficient per se to induce MPDs. The aim of this study was to search for the presence of JAK2 V617F mutation in healthy blood donors with confirmed upper-limit Hct and/or Plts values. Actually, previous studies indicated that some subjects with upper-limit Hct levels have early stages of polycythemia vera (Zanella et al, 1987). We studied 177 consecutive repeat blood donors (92 M, 85 F; median age 45 years, range 19–66) displaying Hct and/or Plts values higher than the 75° percentile of the normal reference distribution (Hct > 0.47 for M and > 0.42 for F; Plts > 300×109/L), confirmed on at least two different occasions in the last 12 months. All subjects had been accepted for blood donation on the basis of negative clinical history and normal results on both physical examination and routine laboratory testing. 83 of them (55 M and 28 F) had upper-limit Hct levels (median 0.48, range 0.47-0.51 for M; 0.43, range 0.42-0.47 for F); 85 had Plts > 300×109/L (median 338×109/L, range 300–454), and 9 donors had both upper-limit Hct and Plts. DNA was extracted from whole blood; all samples were analyzed by allele-specific polymerase chain reaction (PCR) according to Baxter et al (2005), and by fluorescent allele specific PCR (McClure et al, 2006) on ABI PRISM 310 Genetic Analyzer. Ten subjects were found to be positive for V617F mutation by fluorescent PCR, showing a positive signal when compared to a positive control corresponding to 2% of V617F mutated allele. Six of them showed a positive band also on agarose gel when analyzed with allele specific PCR. The presence of mutation was confirmed by enzymatic digestion with BsaXI. Hematological data of mutated subject are reported in the table. No statistically significant differences of hematological parameters were present between V617F positive and negative subjects. In conclusion, the presence of a V617F positive clone (albeit in a small amount), was found in 4% (3 F and 1 M) donors with upper-limit Hct and in 6% (2 F, 4 M) donors with Plts > 300×109/L. The follow up of these subjects will ascertain whether V617F mutation is a prelude to a myeloproliferative disease. Sex Age (years) Hb (g/dl) Hct Plts (×109/L) WBC (x109/L) Upper-limit Hct 1 F 66 15.1 0.45 202 4.85 2 F 51 14.4 0.43 235 6.40 3 F 64 15.7 0.45 198 7.75 4 M 58 15.9 0.48 220 7.30 Plts > 300×109/L 5 F 53 13.7 0.40 360 6.97 6 F 63 13.5 0.40 301 9.2 7 M 47 15.2 0.45 334 8.64 8 M 47 13.8 0.41 316 6.35 9 M 19 15.2 0.44 321 8 10 M 37 16.1 0.45 379 7.9

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JAK2 V617F mutation testing in polycyhemia vera and polycythemia vera-like disease: impact on thrombotic risk.

Experimental Hematology ◽

10.1016/j.exphem.2014.07.092 ◽

2014 ◽

Vol 42 (8) ◽

pp. S26

Author(s):

Rossella Cacciola ◽

Elisa Seria ◽

Maria Torre ◽

Emma Cacciola

Keyword(s):

Polycythemia Vera ◽

Jak2 V617f ◽

Mutation Testing ◽

Jak2 V617f Mutation ◽

Thrombotic Risk ◽

Disease Impact ◽

V617f Mutation

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Refractory anemia with ringed sideroblasts associated with marked thrombocytosis (RARS-T), another myeloproliferative condition characterized by JAK2 V617F mutation

Blood ◽

10.1182/blood-2006-02-005751 ◽

2006 ◽

Vol 108 (7) ◽

pp. 2173-2181 ◽

Cited By ~ 143

Author(s):

Hadrian Szpurka ◽

Ramon Tiu ◽

Gurunathan Murugesan ◽

Samer Aboudola ◽

Eric D. Hsi ◽

...

Keyword(s):

Melting Curve ◽

Jak2 V617f ◽

Jak2 V617f Mutation ◽

Refractory Anemia ◽

Melting Curve Analysis ◽

Jak2 Mutation ◽

Ringed Sideroblasts ◽

Polymerase Chain ◽

V617f Mutation ◽

Reaction Sequencing

Abstract JAK2 V617F mutation recently was identified as a pathogenic factor in typical chronic myeloproliferative diseases (CMPD). Some forms of myelodysplastic syndromes (MDS) show a significant overlap with CMPD (classified as MDS/MPD), but the diagnostic assignment may be challenging. We studied blood or bone marrow from 270 patients with MDS, MDS/MPD, and CMPD for the presence of JAK2 V617F mutation using polymerase chain reaction, sequencing, and melting curve analysis. The detection rate of JAK2 V617F mutants for polycythemia vera, chronic idiopathic myelofibrosis, and essential thrombocythemia (n = 103) was similar to the previously reported results. In typical forms of MDS (n = 89) JAK2 V617F mutation was very rare (n = 2). However, a higher prevalence of this mutation was found in patients with MDS/MPD-U (9 of 35). Within this group, most of the patients harboring JAK2 V617F mutation showed features consistent with the provisional MDS/MPD-U entity refractory anemia with ringed sideroblasts and thrombocytosis (RARS-T). Among 9 RARS-T patients, 6 showed the presence of JAK2 V617F mutation, and in 1 patient without mutation, aberrant, positive phospho-STAT5 staining was seen that is typically present in association with JAK2 V617F mutation. In summary, we found that RARS-T reveals a high frequency of JAK2 V617F mutation and likely constitutes another JAK2 mutation-associated form of CMPD.

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Acquisition of the V617F mutation of JAK2 is a late genetic event in a subset of patients with myeloproliferative disorders

Blood ◽

10.1182/blood-2005-11-009605 ◽

2006 ◽

Vol 108 (4) ◽

pp. 1377-1380 ◽

Cited By ~ 197

Author(s):

Robert Kralovics ◽

Soon-Siong Teo ◽

Sai Li ◽

Alexandre Theocharides ◽

Andreas S. Buser ◽

...

Keyword(s):

Jak2 V617f ◽

Myeloproliferative Disorders ◽

Janus Kinase ◽

Jak2 Mutation ◽

Genetic Event ◽

Allele Specific ◽

Unknown Gene ◽

Clonal Origin ◽

Polymerase Chain ◽

V617f Mutation

AbstractAn acquired gain-of-function mutation in the Janus kinase 2 (JAK2-V617F) is frequently found in patients with myeloproliferative disorders (MPDs). To test the hypothesis that JAK2-V617F is the disease-initiating mutation, we examined whether all cells of clonal origin carry the JAK2-V617F mutation. Using allele-specific polymerase chain reaction (PCR) assays for the JAK2 mutation and for the X-chromosomal clonality markers IDS and MPP1, we found that the percentage of granulocytes and platelets with JAK2-V617F was often markedly lower than the percentage of clonal granulocytes determined by IDS or MPP1 clonality assays in female patients. Using deletions of chromosome 20q (del20q) as an autosomal, X-chromosome–independent clonality marker, we found a similar discrepancy between the percentage of cells carrying JAK2-V617F and del20q. Our results suggest that in a proportion of patients with MPDs, JAK2-V617F occurs on the background of clonal hematopoiesis caused by a somatic mutation in an as-yet-unknown gene.

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Development of a Quantitative Real-Time Polymerase Chain Reaction Assay for the Detection of the JAK2 V617F Mutation

Journal of Molecular Diagnostics ◽

10.2353/jmoldx.2007.060083 ◽

2007 ◽

Vol 9 (1) ◽

pp. 42-46 ◽

Cited By ~ 17

Author(s):

Elizabeth C. Wolstencroft ◽

Katy Hanlon ◽

Lorna W. Harries ◽

Graham R. Standen ◽

Alexander Sternberg ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Real Time ◽

Polymerase Chain Reaction Assay ◽

Jak2 V617f ◽

Jak2 V617f Mutation ◽

Chain Reaction ◽

Polymerase Chain ◽

V617f Mutation

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The JAK2-V617F mutation is frequently present at diagnosis in patients with essential thrombocythemia and polycythemia vera

Blood ◽

10.1182/blood-2006-01-013540 ◽

2006 ◽

Vol 108 (6) ◽

pp. 1865-1867 ◽

Cited By ~ 156

Author(s):

Eric Lippert ◽

Marjorie Boissinot ◽

Robert Kralovics ◽

François Girodon ◽

Irène Dobo ◽

...

Keyword(s):

Polycythemia Vera ◽

Essential Thrombocythemia ◽

Quantitative Polymerase Chain Reaction ◽

Jak2 V617f ◽

Allelic Frequency ◽

Jak2 V617f Mutation ◽

Mrna Levels ◽

Expression Levels ◽

Allele Specific ◽

V617f Mutation

AbstractWe determined the allelic frequency of the JAK2-V617F mutation in DNA and assessed the expression levels of the mutant and wild-type JAK2 mRNA in granulocytes from 60 patients with essential thrombocythemia (ET) and 62 patients with polycythemia vera (PV) at the time of diagnosis. Using allele-specific quantitative polymerase chain reaction (qPCR), we detected JAK2-V617F in 75% of ET and 97% of PV at diagnosis. The total JAK2 mRNA levels were elevated in ET, PV, and secondary and idiopathic erythrocytosis, suggesting that hyperactive hematopoiesis alters JAK2 expression. The expression levels of JAK2-V617F mRNA were variable but strongly correlated with the allelic ratio of JAK2-V617F determined in DNA. Thus, differences in JAK2-V617F expression, markedly lower in ET than in PV, reflected different percentages of granulocytes carrying the mutation. Moreover, allelic ratios higher than 50% JAK2-V617F, indicating the presence of granulocytes homozygous for JAK2-V617F, were found in 70% of PV at diagnosis but never in ET.

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PCR-HRM for Detecting JAK2V617F Gene Mutation: Is It a Sensitive Assay?

Basic & Clinical Cancer Research ◽

10.18502/bccr.v11i4.5722 ◽

2021 ◽

Author(s):

Mitra Rezaei ◽

Mihan PourAbdollah Toutkaboni ◽

Babak Salimi ◽

Sharareh Seifi ◽

Fatemeh Maryam Sheikholeslami

Keyword(s):

Jak2 V617f ◽

Jak2 V617f Mutation ◽

Sensitive Assay ◽

Chain Reaction ◽

Jak2 Mutation ◽

Pcr Rflp ◽

Polymerase Chain ◽

Neoplastic Disorders ◽

V617f Mutation ◽

Sensitivity Specificity

Background: A substitution of G to T at nucleotide 1849 in exon 14 of the Janus kinase2 (JAK2) gene is well recognized in myeloproliferative neoplastic disorders (MPNs). Based on WHO guidelines, detection of the mutation is very important to confirm the disease in suspected patients. Methods: Eighty-seven patients with different background diseases were tested for JAK2 V617F mutation by four different methods, including polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), amplification refractory mutation system (ARMS), polymerase chain reaction-high resolution melting (PCR-HRM), and two different commercial kits. Results: The mean age of patients was 53.38±17.43 years, 72.4% were males, and 37.6% were females. JAK2 mutation was detected in 16 patients (18.3%). Of those, 7 (43.75%) suffered from PV, 5 (31.25%) from ET, 3 (18.75%) from PMF, and 1 (6.15%) from unclassified neoplastic disorders. The frequency of JAK2 mutation was 71.4% (5/7) in PV, 80% (4/5) in ET, and 66.7% (2/3) in PMF patients. The sensi- tivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and GE of PCR-HRM for detection of the JAK2 mutation was 86.7%, 100%, 100%, 97.3%, and 97.7%, respectively. While the sensitivity, specificity, PPV, NPV, and GE of PCR-RFLP were 93.3%, 80.5%, 50%, 98.3%, and 82.7%, respectively. On the other hand, the sensitivity, specificity, PPV, NPV, and GE of ARMS assays were evaluated by about 80%, 96%, 100%, 96%, and 96.5%, respectively. Conclusion: This study showed that PCR-HRM was a more sensitive assay to detect the JAK2 V617F mutation than the other assays. So, it can be used as a quick, easy, and effective method for screening the JAK2 V617F mutation in patients with MPNs disorders. PCR-RFLP must accompany it as a gold standard method for confirmation of the mutation of JAK2 V617F.

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Detection of the Janus kinase 2 V617F mutation using a locked nucleic-acid, real-time polymerase chain reaction assay

African Journal of Laboratory Medicine ◽

10.4102/ajlm.v7i1.658 ◽

2018 ◽

Vol 7 (1) ◽

Author(s):

Tshiphiri Senamela ◽

Marleen Kock ◽

Piet Becker ◽

Joachim J.C. Potgieter

Keyword(s):

Polymerase Chain Reaction ◽

Nucleic Acid ◽

Real Time ◽

Jak2 V617f ◽

Locked Nucleic Acid ◽

Jak2 V617f Mutation ◽

Chain Reaction ◽

Pcr Assay ◽

Polymerase Chain ◽

V617f Mutation

The purpose of this study was to develop a real time polymerase chain reaction (PCR) assay for the detection of the JAK2 V617F mutation that could be used in diagnostic laboratories. Sanger sequencing and a newly developed locked nucleic-acid, real-time PCR assay were used to detect the JAK2 V617F mutation. There was 100% agreement between the sequencing and PCR analysis. Both assays were able to detect the mutation in all 24 of the 60 test specimens harbouring the mutation.

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