Carotid body paraganglioma and SDHD mutation in a Greek family.

Carotid body (CB) is a highly specialized paraganglion originating from the neural crest ectoderm. CB paraganglion can be caused either by a genetic predisposition (hereditary paraganglia) or by chronic hypoxic stimulation. Germline mutations in any of the following genes: SDHD, SDHC, SDHB, PGL2 or other unknown genes, can cause paragangliomas (PGLs). We studied a Greek family in which the two daughters had carotid body paraganglioma, whereas both parents did not. RNA extraction, reverse transcriptase polymerase chain reaction and direct DNA sequencing were performed, in order to identify SDHD mutations in all four exons. Our results revealed the existence of the missense mutation Y114C, in exon-4 of the SDHD gene, in the unaffected father and both affected sisters. DNA testing was performed, for the first time in Greece, on patients with carotid body tumor. This marks a new geographical location, in the literature, for this mutation.