Alternate test when clinical/family history is classic for HHT. Test does not detect large duplications/deletions.
Polymerase Chain Reaction/Sequencing
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Transport 3 mL whole blood. (Min: 1 mL)
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Background Information for Hereditary Hemorrhagic Telangiectasia (ACVRL1 and ENG) Sequencing
Characteristics: Recurrent nosebleeds, telangiectases (mouth, face, hands, GI tract), arteriovenous malformations (lung, brain, liver, spine).
Inheritance: Autosomal dominant
Penetrance: Approaches 100 percent by age 40.
Cause: Pathogenic variants in the endoglin (ENG), activin A receptor type II-like 1 (ACVRL1 or ALK1), SMAD4 or other unidentified gene(s).
Clinical Sensitivity: Approximately 75 percent
Methodology: Bidirectional sequencing of the coding regions and intron-exon boundaries of ENG and ACVRL1, the 5' untranslated region of ENG, and a region of ACVRL1 intron 9 encompassing the CT-rich variant hotspot region.
Analytic Sensitivity and Specificity: 99 percent
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region and intronic mutations, large deletions/duplications, and mutations in genes other than ENG and ACVRL1 will not be detected.
Compliance Statement C: For human genetic inheritable conditions and mutations. This test was developed and its performance characteristics determined by ARUP Laboratories. The U. S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
81406 (ENG); 81479
|Component Test Code*||Component Chart Name||LOINC|
|2001357||HHT, Sequencing - Specimen|
- ACVRL1 and ENG sequencing
- HHT sequencing