Frequency of Non-Type I/II CALR Mutations in Patients Undergoing Molecular Diagnostics for…

Cohort studyDiseases (Basel, Switzerland)· May 2026

Frequency of Non-Type I/II CALR Mutations in Patients Undergoing Molecular Diagnostics for Myeloproliferative Neoplasms.

Tatiana Makarik, Elena Nikulina, Svetlana Treglasova … Andrey Sudarikov

Molecular Genetic PathologyCohort studyDiagnosisQ1IF 4.0

Non-type I/II CALR mutations found in 0.8% of myeloproliferative neoplasms-suspected cases tested

Frequency of Non-Type I/II CALR Mutations in Patients Undergoing Molecular Diagnostics for Myeloproliferative Neoplasms.

Tatiana Makarik … Andrey Sudarikov

Diseases (Basel, Switzerland) · May 2026 · Q1 in General Medicine

Background

Somatic CALR gene insertions/deletions in exon 9, causing frameshift, are a diagnostic sign of myeloproliferative neoplasms (myeloproliferative neoplasms).

Purpose

This study evaluates the frequency of rare mutations and demonstrates a germline rather than somatic nature for some of them.

Methods

A retrospective analysis of 8417 blood samples subjected to molecular diagnosis of myeloproliferative neoplasm (myeloproliferative neoplasms) was performed.

n = 68 cases

Results

0.8%

non-type I/II CALR variants are rare and often unrelated to the myeloproliferative neoplasms diagnosis

n = 68 cases

More results

We have identified 632 C ALR gene mutation-positive cases.

Most of the cases were typical insertions/deletions (5 bp/52 bp).

Non-type I/II frameshift or nonframeshift mutations were observed in 68 cases (11%).

The buccal swab samples obtained from 4 patients confirmed the germline nature of these variants.

“

Conclusion · 1 of 2

Non-type I/II CALR mutations, according to our data, could be found in 0.8% of myeloproliferative neoplasms-suspected cases, and may not be associated with the diagnosis.

Conclusion · 2 of 2

The detection of a non-standard CALR mutation with an allelic frequency close to 50% should raise suspicion of the possibility of a germline CALR variant, and such cases should be investigated further.

Frequency of Non-Type I/II CALR Mutations in Patients Undergoing Molecular Diagnostics for Myeloproliferative Neoplasms.

Frequency of Non-Type I/II CALR Mutations in Patients Undergoing Molecular Diagnostics for Myeloproliferative Neoplasms.

Related papers