Test Catalog

Test ID: KVAR2    
Known Variant Analysis-2 Variants

Useful For Suggests clinical disorders or settings where the test may be helpful

Diagnostic or predictive testing for specific conditions when 2 DNA sequence variants of interest have been previously identified in a family member, and follow-up testing for these specific variants in other family members is desired


Carrier screening for individuals at risk for having 2 DNA sequence variants that were previously identified in a family member


Segregation analysis for 2 familial DNA sequence variants

Genetics Test Information Provides information that may help with selection of the correct genetic test or proper submission of the test request

Documentation of the specific familial variant is required and must be provided with the specimen in order to perform this test.


This test should be used for targeted (site-specific) testing for 2 sequence variants identified in any of the genes listed in the Clinical Information section.


Note: If testing is needed for a gene not on this list, see 1 of the following:

-PKLRG / Pyruvate Kinase Liver and Red Blood Cell (PKLR) Full Gene Sequencing and Large Deletion Detection, testing for known familial large deletions in the PKLR gene. PKLR gene sequencing for 2 variants may be requested by ordering using this test (KVAR2).

-FMTT / Familial Mutation, Targeted Testing, which includes targeted and site-specific and deletion or duplication testing for additional genes.

Reflex Tests Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.

Test IDReporting NameAvailable SeparatelyAlways Performed
MATCCMaternal Cell Contamination, BYesNo
CULFBFibroblast Culture for Genetic TestYesNo
CULAFAmniotic Fluid Culture/Genetic TestYesNo

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

For prenatal specimens only: If amniotic fluid (nonconfluent cultured cells) is received, amniotic fluid culture will be added and charged separately. If chorionic villus specimen (nonconfluent cultured cells) is received, fibroblast culture will be added and charged separately. For any prenatal specimen that is received, maternal cell contamination studies will be added.


If the 2 familial variants were previously identified at an outside laboratory, sending DNA from a family member with a positive genetic test result to be used as a positive control is strongly recommended to ensure that the specific familial variant can be detected by our laboratory. Proband samples should be sent as a separate (KVAR2) order, under the proband's identifiers (ie, do not send the patient and proband samples under the same order). If a positive control is not provided, negative results will be reported with a stated limitation that the laboratory's ability to detect the familial variant has not been confirmed and a false-negative result cannot be ruled out.

Special Instructions Library of PDFs including pertinent information and forms related to the test

Method Name A short description of the method used to perform the test

Polymerase Chain Reaction (PCR) Followed by DNA Sequencing Analysis

NY State Available Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name Lists a shorter or abbreviated version of the Published Name for a test

Known Variant Analysis-2 Variants

Aliases Lists additional common names for a test, as an aid in searching

Activin A Receptor, Type II-Like I
Aortic aneurysm
Aortic dilatation
Aortic dissection
Arrhythmogenic right ventricular cardiomyopathy (ARVC)
Arrhythmogenic right ventricular dysplasia (ARVD)
Arterial tortuosity
Arteriovenous Malformations (AVM)
Brugada syndrome
Cardiofaciocutaneous (CFC)
Costello Syndrome (CS)
Dilated Cardiomyopathy (DCM)
Familial Hypercholesterolemia (FH)
Familial Mutation
Familial Thoracic Aortic Aneurysm and Dissection (FTAAD)
Hereditary Hemorrhagic Telangiectasia (HHT)
Hypertrophic Cardiomyopathy (HCM)
Known Mutation
Known Variant
Left ventricular non-compaction (LVNC)
LEOPARD Syndrome (LS)
Loeys-Dietz syndrome
Marfan syndrome (MFS)
Mitral valve prolapse
Multiple Lentigines syndrome
Noonan Syndrome (NS)
Osler-Rendu-Weber (ORW) Disease
Osler-Weber-Rendu (OWR) Disease
Thoracic Aortic Aneurysm and Dissection (TAAD)
Vascular aneurysm
Atypical Hemolytic Uremic Syndrome (aHUS)
Autoinflammatory bone disease
B-cell Deficiency
Inflammatory Bowel Disease
Severe Combined Immunodeficiency (SCID)