ENG Mutation Analysis
Endoglin protein, encoed by the ENG gene, is a type I membrane glycoprotein located on cell surfaces. It is a component of the transforming growth factor beta receptor complex and binds TGFB1 and TGFB3 with high affinity and TGF-beta 2 less efficiently. It interacts with TCTEX1D4 and ARRB2. In addition to TGF-beta signaling, endoglin was found to be involved in the cytoskeletal organization affecting cell morphology and migration. Endoglin has a role in the development of the cardiovascular system and in vascular remodeling. The ENG gene contains 15 exons spanning over 250 kb of genomic distance that was mapped to chromosome 9q34.11. Mutations in ENG gene were associated with the autosomal dominant disorders of hereditary hemorrhagic telangiectasia type 1 (HHT1) and pulmonary arterial hypertension (PAH). Definitive genotype/phenotype correlations have not been described.
The John Welsh Cardiovascular Diagnostic Laboratory offers molecular genetic testing for ENG mutations. Individuals are tested by automatic fluorescent DNA sequencing of the coding exons of the ENG gene. We strongly recommend initial testing of a clearly affected individual, if available, in order to provide the greatest test sensitivity and clearest interpretation of results for subsequent family members. Genetic counseling is recommended for all individuals.
Reasons for Referral
Molecular confirmation of the diagnosis of pulmonary arterial hypertension (PAH) and hereditary hemorrhagic telangiectasia type 1 (HHT1)
Genomic DNA is analyzed for ENG mutations by automatic fluorescent DNA sequencing of the coding exons of the ENG gene, as well as the exon/intron junctions and a portion of the 3` untranslated region. Patient DNA is sequenced in both the forward and reverse orientations. If a mutation is identified, additional family members are analyzed only for the familial mutation by automatic fluorescent DNA sequencing.
|Service||Direct and Institutional Billing||CPT Codes|
|Index Case (Male or Female)||$800 per sample||81406, G0452|
|Additional Family Members||$300 per sample; known familial mutation only||81403, G0452|
DNA Sequencing Analysis: Approximately 99 percent detection of mutations in the coding exons of ENG
Blood (preferred): EDTA (purple-top) tubes: Adult: 5 cc, Child: 5 cc, Infant: 2-3 cc
Tissue: Frozen (preferred), RNAlater, Formalin-fixed, Paraffin-embedded
Other Body Fluids: Call to inquire
Buccal Swabs: One swab from each cheek