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Background: Genetic testing is recommended when the probability of a disease-associated germline mutation exceeds 10%. Germline mutations are found in approximately 25% of individuals with phaeochromcytoma (PCC) or paraganglioma (PGL); however, genetic heterogeneity for PCC/PGL means many genes may require sequencing. A phenotype-directed iterative approach may limit costs but may also delay diagnosis, and will not detect mutations in genes not previously associated with PCC/PGL., Objective: To assess whether whole exome sequencing (WES) was efficient and sensitive for mutation detection in PCC/PGL., Methods: Whole exome sequencing was performed on blinded samples from eleven individuals with PCC/PGL and known mutations. Illumina TruSeq (Illumina Inc, San Diego, CA, USA) was used for exome capture of seven samples, and NimbleGen SeqCap EZ v3.0 (Roche NimbleGen Inc, Basel, Switzerland) for five samples (one sample was repeated). Massive parallel sequencing was performed on multiplexed samples. Sequencing data were called using Genome Analysis Toolkit and annotated using annovar. Data were assessed for coding variants in RET, NF1, VHL, SDHD, SDHB, SDHC, SDHA, SDHAF2, KIF1B, TMEM127, EGLN1 and MAX. Target capture of five exome capture platforms was compared., Results: Six of seven mutations were detected using Illumina TruSeq exome capture. All five mutations were detected using NimbleGen SeqCap EZ v3.0 platform, including the mutation missed using Illumina TruSeq capture. Target capture for exons in known PCC/PGL genes differs substantially between platforms. Exome sequencing was inexpensive (<$A800 per sample for reagents) and rapid (results <5 weeks from sample reception)., Conclusion: Whole exome sequencing is sensitive, rapid and efficient for detection of PCC/PGL germline mutations. However, capture platform selection is critical to maximize sensitivity., (© 2013 John Wiley & Sons Ltd.)

Objective: Germline mutations in succinate dehydrogenase (SDH)B, SDHC and SDHD, encoding three of the four subunits of mitochondrial complex II, have been implicated in the tumourigenesis of familial paragangliomas and phaeochromocytomas. Twenty-three SDHB mutations have been identified to date., Patients: We present a novel missense SDHB exon 2 mutation (c.118 A > G; K40E) identified in an Australian family. The proband was diagnosed with phaeochromocytoma at an early age following an unexpected hypertensive crisis and was found to be SDHB mutation-positive. Subsequent genetic screening of 26 family members has identified 17 mutation-positive relatives. In addition to the proband, four mutation positive relatives were found to have clinical symptoms or a lesion and/or catecholamine excess after the identification of the mutation led to further evaluation. Both the proband and an uncle have required surgical removal of a tumour., Conclusions: This family indicates the importance of germline screening of first-degree relatives when a patient presents with an apparently sporadic extra adrenal phaeochromocytoma at a young age or whenever a patient with a nonsecretory paraganglioma is found.