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Test ID HEMP Hereditary Erythrocytosis Mutations, Whole Blood

Useful For

Definitive evaluation of an individual with JAK2-negative erythrocytosis associated with lifelong sustained increased red blood cell (RBC) mass, elevated RBC count, hemoglobin, or hematocrit


This test is not intended for prenatal diagnosis.

Genetics Test Information

This test is a third-order test and should be ordered when the patient meets the following criteria: diagnosis of erythrocytosis, JAK2 V617F is negative, and p50 values are normal.

Method Name

Polymerase Chain Reaction (PCR) Amplification/Sanger Sequence Analysis

Reporting Name

Hereditary Erythrocytosis Mut, B

Specimen Type

Whole blood

Ordering Guidance

This is a third-order test for specific variants. For a complete evaluation including p50 testing, hemoglobin electrophoresis testing, and hereditary erythrocytosis variant analysis in an algorithmic fashion, order REVE1 / Erythrocytosis Evaluation, Whole Blood.


This test does not provide a serum erythropoietin (EPO) level. If EPO testing is desired, see EPO / Erythropoietin, Serum.

Specimen Required

Container/Tube: Lavender top (EDTA)

Specimen Volume: 3 mL

Collection Instructions: Send whole blood specimen in original tube. Do not aliquot.

Specimen Minimum Volume

0.5 mL

Specimen Stability Information

Specimen Type Temperature Time Special Container
Whole blood Refrigerated (preferred) 30 days
  Ambient  14 days

Reference Values

An interpretive report will be provided.

Day(s) Performed

Monday through Friday

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

81479-Unlisted molecular pathology procedure

LOINC Code Information

Test ID Test Order Name Order LOINC Value
HEMP Hereditary Erythrocytosis Mut, B In Process


Result ID Test Result Name Result LOINC Value
34645 EPOR Gene Sequencing Result 82939-0
34646 PHD2 Gene Sequencing Result 82939-0
34647 HIF2A Gene Sequencing Result 82939-0
34648 Molecular Interpretation 69047-9
35000 Reviewed By 18771-6

Test Classification

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

Profile Information

Test ID Reporting Name Available Separately Always Performed
MINT Molecular Interpretation No Yes
EPOR EPOR Gene, Mutation Analysis, B No Yes
HIF2A HIF2A Gene, Mutation Analysis, B No Yes
PHD2 PHD2 Gene, Mutation Analysis, B No Yes

Testing Algorithm

This evaluation is recommended for patients presenting with lifelong erythrocytosis, usually with a positive family history of similar symptoms. Polycythemia vera should be excluded prior to testing as it is much more common than hereditary erythrocytosis and can be present even in young patients. A JAK2 V617F or JAK2 exon 12 variant should not be present. Additionally, p50 testing should be performed and a normal result confirmed before ordering this test.


Additional testing for BPGM full gene sequencing and VHL gene erythrocytosis variant analysis will always be performed at an additional charge.


See Erythrocytosis Evaluation Testing Algorithm in Special Instructions.

Report Available

10 to 25 days

NY State Approved



1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available in Special Instructions:

-Informed Consent for Genetic Testing (T576)

-Informed Consent for Genetic Testing-Spanish (T826)

2. Erythrocytosis Patient Information (T694) in Special Instructions

3. If not ordering electronically, complete, print, and send a Benign Hematology Test Request Form (T755) with the specimen.

Additional Tests

Test ID Reporting Name Available Separately Always Performed
BPGMM BPGM Full Gene Sequencing Yes Yes
VHLE VHL Gene Erythrocytosis Mutations No, (Order VHLZZ) Yes