There are four genes known to cause hereditary PGL/PCC syndrome; SDHD, SDHC, SDHB, and SDHAF2. The SDHD, SDHC, and SDHB genes encode three of the four subunits of the mitochondrial enzyme succinate dehyodrongenase (SDH) also known as mitochondrial complex II. The SDHAF2 gene is involved with the assembly of the SDH complex.
Mutations in the SDHB gene (1p36.13) are associated with extra-adrenal sympathetic paragangliomas that have a greater likelihood of being malignant. About 20-25% of hereditary PGL/PCC syndrome cases are due to mutations in the SDHB gene. Sequencing analysis will detect approximately 70-90% of disease causing mutations. About 10% of mutations in the SDHB gene are deletions. The penetrance of hereditary PGL/PCC in individuals with SDHB mutations is approximately 77% by 50 years of age.
Please note that mutations in the SDHB gene can cause paraganglioma and gastric stromal sarcoma, also known as Carney-Stratakis syndrome.
This test is for sequencing of the SDHB gene only.
- Confirmation of a clinical diagnosis of hereditary PGL/PCC syndrome.
Analytical Sensitivity: ~99%
Submit only 1 of the following specimen types
Preferred specimen type: Whole Blood
Type: Whole Blood
Specimen Requirements:In EDTA (purple top) or ACD (yellow top) tube:
Infants (<2 years): 2-3 ml
Children (>2 years): 3-5 ml
Older Children & Adults: 5-10 ml
Specimen Collection and Shipping: Refrigerate until time of shipment. Ship sample within 5 days of collection at room temperature with overnight delivery.
Specimen Requirements:OrageneTM Saliva Collection kit (available through EGL) used according to manufacturer instructions.
Specimen Collection and Shipping: Store sample at room temperature. Ship sample within 5 days of collection at room temperature with overnight delivery.
- Custom diagnostic mutation analysis (KM) is available to family members if mutations are identified by targeted mutation testing or sequencing analysis.
- Prenatal testing is available only for known familial mutations to individuals who are confirmed carriers of mutations. Please contact the laboratory genetic counselor to discuss appropriate testing prior to collecting a prenatal specimen.