Test Code PKLRZ PKLR Full Gene Analysis, Varies
Ordering Guidance
Preliminary screening tests, such as complete blood cell count with peripheral smear, direct Coombs test, and pyruvate kinase enzyme activity assays (preferably as a part of EEEV1 / Red Blood Cell [RBC] Enzyme Evaluation, Blood) should be performed before ordering this test.
Targeted testing (also called site-specific or known variants testing) is available for variants identified in the PKLR gene. See FMTT / Familial Variant, Targeted Testing, Varies. To obtain more information about this testing option, call 800-533-1710.
Necessary Information
1. PKLR Gene Sequencing Patient Information is required. Testing may proceed without the patient information; however, it aids in providing a more thorough interpretation. Ordering healthcare professionals are strongly encouraged to complete the form and send it with the specimen.
2. Include healthcare professional's name and phone number with specimen.
Specimen Required
Specimen Type: Whole blood
Patient Preparation: A previous bone marrow transplant from an allogenic donor will interfere with testing. For instructions for testing patients who have received a bone marrow transplant, call 800-533-1710.
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Yellow top (ACD)
Specimen Volume: 3 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in original tube. Do not aliquot.
Specimen Stability Information: Ambient (preferred) 4 days/Refrigerated
Forms
1. PKLR Gene Sequencing Patient Information (T766) is required.
2. 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:
Secondary ID
610058Useful For
Aiding in the diagnosis of pyruvate kinase (PK) deficiency
Ascertaining a causative variant in the PKLR gene of patients with low or relatively low levels of erythrocytic PK enzymatic activity
Ascertaining carrier status of family members of individuals diagnosed with PK deficiency for genetic counseling purposes
Special Instructions
Method Name
Sequence Capture and Targeted Next-Generation Sequencing (NGS) followed by Polymerase Chain Reaction (PCR) and Sanger Sequencing
Specimen Type
VariesSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Varies | Varies |
Reject Due To
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.Reference Values
An interpretive report will be provided.
Interpretation
All detected variants are evaluated according to American College of Medical Genetics and Genomics recommendations.(3) Variants are classified based on known, predicted, or possible pathogenicity and reported with interpretive comments detailing their potential or known significance.
Method Description
Next-generation sequencing (NGS) and/or Sanger sequencing are performed to test for the presence of variants in coding regions and intron/exon boundaries of the PKLR gene, as well as some other regions that have known disease-causing variants. The human genome reference GRCh37/hg19 build was used for sequence read alignment. At least 99% of the bases are covered at a read depth over 20X. Sensitivity is estimated at above 99% for single nucleotide variants, above 94% for deletions-insertions (delins) less than 40 base pairs (bp), above 95% for deletions up to 75 bp, and insertions up to 47 bp. NGS and/or a polymerase chain reaction-based quantitative method is performed to test for the presence of deletions and duplications in the PKLR gene.
There may be regions of this gene that cannot be effectively evaluated by sequencing or deletion and duplication analysis as a result of technical limitations of the assay, including regions of homology, high guanine-cytosine (GC) content, and repetitive sequences.(Unpublished Mayo method)
The reference transcript for PKLR gene is NM_000298.6. Reference transcript numbers may be updated due to transcript re-versioning. Always refer to the final patient report for gene transcript information referenced at the time of testing. Confirmation of select reportable variants may be performed by alternate methodologies based on internal laboratory criteria.
The following additional noncoding variants are being analyzed by this test:
±30 bp flanking exons, c.-98 to c.-1, c.1269+43T>C, NM_181871.3 Exon 1
Day(s) Performed
Varies
Report Available
28 to 42 daysSpecimen Retention Time
Whole blood: 2 weeks (if available); Extracted DNA: 3 monthsPerforming Laboratory
Mayo Clinic Laboratories in RochesterCPT Code Information
81405
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
PKLRZ | PKLR Full Gene Analysis | 94212-8 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
618935 | Test Description | 62364-5 |
618936 | Specimen | 31208-2 |
618937 | Source | 31208-2 |
618938 | Result Summary | 50397-9 |
618939 | Result | 82939-0 |
618940 | Interpretation | 59465-5 |
618941 | Additional Results | 82939-0 |
621816 | Resources | 99622-3 |
621817 | Additional Information | 48767-8 |
621818 | Method | 85069-3 |
621819 | Genes Analyzed | 82939-0 |
621820 | Disclaimer | 62364-5 |
621821 | Released By | 18771-6 |