DSC2 Mutation Analysis
Desmocollin 2, encoded by DSC2 gene, is a calcium-dependent glycoprotein that is a member of the desmocollin subfamily of the cadherin superfamily. Along with the desmogleins, these desmocollins are found primarily in epithelial cells where they constitute the adhesive proteins of the desmosome and are required for cell adhesion. DSC2 gene contains 16 exons and spans around 36 kb genomic distance that was mapped to chromsome 18q12.1. Alternative splicing of exon 16 results in two distinct protein isoforms. Mutations in DSC2 are associated with familial arrhythmogenic right ventricular dysplasia/cardiomyopathy type 11 (ARVD/C11). ARVD/C is an autosomal dominant disease characterized by partial degeneration of the myocardium of the right ventricle, electrical instability and sudden death. Definitive genotype/phenotype correlations have not been described.
The John Welsh Cardiovascular Diagnostic Laboratory offers molecular genetic testing for DSC2 mutations. Individuals are tested by automatic fluorescent DNA sequencing of the coding exons of the DSC2 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 familial arrhythmogenic right ventricular dysplasia/cardiomyopathy type 11 (ARVD/C11).
Genomic DNA is analyzed for DSC2 mutations by automatic fluorescent DNA sequencing of the coding exons of the DSC2 gene, as well as the exon/intron junctions and a portion of the 5' and 3' untranslated regions. 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 (Full Gene)||$1200 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 coding exons 1-16 of DSC2.
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