CALR mutation (exon 9)
Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.
| ID | BIO-CALR |
|---|---|
| Type | Biomarker |
| Aliases | CALR mutationCalreticulin mutationМутація CALR (екзон 9) |
| Status | reviewed 2026-04-27 | pending_clinical_signoff |
| Diseases | None declared |
| Sources | SRC-ESMO-MPN-2015 SRC-NCCN-MPN-2025 |
Biomarker Facts
| Biomarker type | gene_mutation |
|---|---|
| Mutation details | {"exon": "9", "functional_impact": "Mutant CALR binds and constitutively activates MPL (thrombopoietin receptor) → JAK-STAT signaling", "gene": "CALR", "gene_hugo_id": "HGNC:1455", "hotspots": ["Type 1 — c.1092_1143del52 (52-bp deletion; ~55% of CALR-mut MPN)", "Type 2 — c.1154_1155insTTGTC (5-bp insertion; ~35%)", "Other type-1-like / type-2-like (~10%)"], "variant_type": "frameshift indel (exon 9)"} |
| Measurement | MethodPCR + fragment-length analysis (preferred — distinguishes type 1 vs type 2) OR Sanger / NGS for exact variant Unitscategorical; variant type reported Sensitivity requirementStandard PCR / fragment-length |
| Related biomarkers | BIO-JAK2 |
Notes
Diagnostic criterion for ET (~25%) and PMF (~25–30%); essentially absent in PV. Mutually exclusive with JAK2 V617F and MPL W515 (the three drive ~95% of MPNs). Type 1 (52-bp del) carries more myelofibrotic phenotype and better OS in PMF; type 2 (5-bp ins) more thrombocytosis-predominant ET phenotype with lower thrombosis risk. JAK inhibitors (ruxolitinib, momelotinib, fedratinib, pacritinib) are not mutation-specific — they target downstream JAK-STAT, so they work in CALR-, JAK2-, and MPL-driven disease. Mutant CALR is also a tumor-specific neoantigen — anti-mutCALR immunotherapy in early-phase trials.
Used By
Actionability
BMA-CALR-ET- CALR exon 9 indels are the second most common driver in ET (~25-30%) and a WHO 2022 / ICC...BMA-CALR-PMF- CALR exon 9 indels are the second most common driver in PMF (~25%) and a WHO 2022 / ICC 2...
Biomarker
BIO-JAK2- JAK2 mutation (V617F or exon 12)