What are the limitations of the jak2v617f interpreter?

While the jak2v617f interpreter is highly validated, it should not replace clinical judgment. OpiCalc provides the latest evidence-based limitations for the jak2v617f interpreter to ensure safe bedside use and optimal diagnostic accuracy.

How does the jak2v617f interpreter compare to other Hematology scores?

The jak2v617f interpreter is a gold-standard diagnostic tool. OpiCalc provides side-by-side clinical guidance to help clinicians choose the most specific evidence-based tool for their patient's presentation.

Is the jak2v617f interpreter free to use?

Yes. OpiCalc provides the jak2v617f interpreter completely ad-free and optimized for mobile bedside use, ensuring you can calculate medical risk swiftly and without distraction.

OpiCalc

927 Clinical Tools

OpiCalc

4Ts Score (HIT)aaIPI (Age-adjusted IPI)ABC Score (Massive Transfusion)Absolute Neutrophil Count Age-adjusted D-dimer Threshold aGvHD Grading (Glucksberg/MAGIC)AL Amyloidosis Staging (Mayo)Anti-Xa Monitoring Interpreter Antiphospholipid Syndrome Classification Binet / Rai Staging (CML)Blood Volume Calculator Caprini VTE Risk CISNE Score CLL-IPI Coombs-Negative Haemolysis Checklist Corrected Reticulocyte Count CRS Grading (ASTCT 2019)DAT Interpretation Algorithm Deauville Score Interpreter DIC Score (ISTH)DIPSS (MF)DIPSS-Plus (MF)DOAC Dose Selector DOAC Renal Dose Adjustment DRI (Disease Risk Index)Durie-Salmon Staging (historical)EBMT Risk Score ELN 2022 AML Risk Classification ELTS Score (CML)England & Fraser Index EUTOS Score (CML)Expected Hb Rise per RBC Unit Factor Inhibitor Bethesda Titre Interpreter Febrile Neutropaenia Risk (MASCC)Fibrinogen Replacement FLIPI (Follicular Lymphoma IPI)FLIPI-2 French TTP Score GAPSS (Global APS Score)Haemophilia Severity Classification HbS Percentage Target Calculator HCT-CI (Comorbidity Index)HEP Score Heparin Nomogram (Weight-based)Hepatic Iron Index HERDOO2 Rule HFE Haemochromatosis Risk Estimator ICANS Grading (ASTCT 2019)IMWG Response Criteria (Myeloma)IPI (International Prognostic Index)IPSID / Lugano Classification IPSS-M (Molecular IPSS)IPSS-R (Revised IPSS for MDS)Iron Deficit Calculator (Ganzoni Formula)ISS (Myeloma)ISTH Bleeding Assessment Tool (BAT)ISTH Non-Overt DIC Score ITP Bleeding Score iwCLL Response Criteria (2018)IWG ITP Response Criteria JAK2V617F Allele Burden Interpreter Karnofsky Performance Scale Leucostasis Risk Threshold Lupus Anticoagulant (LAC) Reporting Framework MAGIC aGvHD Biomarker Score MCV-based Anaemia Algorithm Mentzer Index MIPI (MCL IPI)MIPSS70+ v2.0 (MF)Mixing Study Interpretation MRD Assessment Threshold Interpreter mSMART 3.0 (Myeloma)MTP Activation Criteria NCCN-IPI NIH Chronic GvHD Scoring NTDT Iron Burden Estimator Padua RAM PBT (Paediatric BAT)PCNSL MSKCC Score PERC Rule Perioperative Anticoagulation Bridging PESI Score (PE Mortality)PLASMIC Score Platelet Increment Calculator (CCI)PNH Clone Size Interpreter R-IPI (Revised IPI)R-ISS (Revised ISS)Reticulocyte Index (RPI)Revised Geneva Score (PE)Revised Response Criteria (NHL)Revised Zubrod / ECOG Performance Shine & Lal Index Sickle Cell Disease Risk (TCD)SLiM-CRAB Criteria SOKAL Score (CML)Sokal/EUTOS/ELTS Comparison sPESI (Simplified PESI)TACO Risk Score Thalassaemia Transfusion Threshold Thrombocytopaenia Differential Thrombophilia Screening Eligibility Algorithm Time in Therapeutic Range (TTR)TLS Risk Classification Transferrin Saturation Calculator Vienna Prediction Model von Willebrand Factor Activity Interpreter Warfarin Dose Calculator Wells Score (DVT)Wells Score (PE)WHO 2022 AML Classification Mapper WHO Bleeding Scale YEARS Algorithm

JAK2V617F Allele Burden Interpreter

JAK2 V617F: The most common driver mutation in MPNs. Variant Allele Frequency (VAF) helps distinguish between phenotypes and assess biological drive.

Variant Allele Frequency (%)

Guidelines & Evidence

Clinical Details

Section 1

When to Use

Evaluating patients with suspected Myeloproliferative Neoplasms (MPN).

Interpreting VAF (Variant Allele Frequency) in the context of Polycythemia Vera (PV), Essential Thrombocythemia (ET), or Primary Myelofibrosis (PMF).

Distinguishing clonal MPN from secondary/reactive erythrocytosis or thrombocytosis.

Patient Population

Patients presenting with elevated haemoglobin, haematocrit, or platelet counts of unclear etiology.

Section 2

Formula & Logic

JAK2 V617F Positivity Rates

Condition	Prevalence (%)
Polycythemia Vera (PV)	> 95%
Essential Thrombocythemia (ET)	50 - 60%
Primary Myelofibrosis (PMF)	50 - 60%
Secondary Polycythemia	0%

Low VAF (CHIP)

A very low VAF (< 1-2%) in an otherwise healthy individual might represent Clonal Hematopoiesis of Indeterminate Potential (CHIP) rather than a definitive MPN.

Section 3

Pearls/Pitfalls

VAF and Phenotype

Higher VAF (> 50%) is more common in PV and PMF, often reflecting homozygous mutations due to uniparental disomy. Lower VAF is typically seen in ET.

Triple Negative MPN

If JAK2 V617F is negative in suspected ET or PMF, test for CALR (Calreticulin) and MPL mutations. If all three are negative, the patient is "Triple Negative".

Section 4

Evidence Appraisal

Guidelines

Somatic mutations of calreticulin in myeloproliferative neoplasms.

Klampfl T et al. • NEJM. 2013;369(25):2379-90.

View Source

Acquired mutation of the tyrosine kinase JAK2 in human myeloproliferative diseases.

Baxter EJ et al. • Lancet. 2005;365(9464):1054-61.

View Source

Section 5

Literature

Discovery

Discovered simultaneously by four independent groups in 2005. It revolutionized the diagnosis of MPNs, which were previously diagnoses of exclusion.

Last Comprehensive Review: 2026

Related Hematology Tools

IPSS-R

IPSS-M

WHO 2022 AML Classification Mapper

ELN 2022 AML Risk Classification

Have feedback about this calculator?Let us know.