- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 2 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: Hereditary paraganglioma-pheochromocytoma (PGL/PCC) syndromes are characterized by paragangliomas (neuroendocrine tumors of the autonomic nervous system) and pheochromocytomas (paragangliomas of the adrenal medulla). Pathogenic germline mutations in a number of genes, including SDHD, predispose to paraganglioma and pheochromocytoma.
Incidence: About 1 in 300,000 per year.
Inheritance: Autosomal dominant; disease manifestations generally occur when mutations in SDHD are inherited from the father (but not from the mother) due to a parent of origin effect.
Cause: Pathogenic succinate dehydrogenase, subunits B, C, and D (SDHB, SDHC, and SDHD) gene mutations. Mutations in other genes, including TMEM127, EGLN1, MAX, SDHA, and SDHAF2, may also be causative.
Clinical Sensitivity: 15 percent.
Methodology: Bidirectional sequencing of all coding regions and intron-exon boundaries of the SDHD gene; multiplex ligation-dependent probe amplification (MLPA) to detect large SDHD deletions/duplications.
Analytical Sensitivity and Specificity: Sequencing: 99 percent. MLPA: 90 and 99 percent, respectively.
Limitations:Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations and deep intronic mutations will not be detected. The breakpoints of large deletions/duplications will not be determined. Mutations in genes other than SDHD are not evaluated.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|2007123||HPGL-PCC (SDHD) Seq, DelDup Specimen||31208-2|
|2007124||HPGL-PCC (SDHD) Seq, DelDup Interp||41061-3|
- Succinate Dehydrogenase genetic assay
- Hereditary PGL/PCC Type 1 molecular assay
- Paraganglioma (SDHD) Sequencing and Deletion/Duplication
- PCC (SDHD) Sequencing and Deletion/Duplication
- PGL (SDHD) Sequencing and Deletion/Duplication
- Pheochromocytoma (SDHD) Sequencing and Deletion/Duplication
- SDHD Gene
- SDHD Sequencing and Deletion/Duplication
- Stromal Tumor (SDHD) Sequencing and Deletion/Duplication
- Succinate Dehydrogenase, subset C (SDHD) Sequencing and Deletion/Duplication