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GENATLAS PHENOTYPE

last update : 08-11-2016

Symbol	PGL4
Location	1p36.13
Name	hereditary paraganglioma 4
Corresponding gene	SDHB
Main clinical features	hereditary susceptibility to PGL development of slow-growing, highly vascular, generally benign neoplasms, usually of the head and neck with the carotid body as the major tumor site, neuroectodermal origin rare tumours that derive from minute, diffuse paraganglionic tissues which are located internally and centrally around the major arteries, nerves, within organs and distributed from the skull base to the pelvic floor (Baysal 2008) pheochromocytoma, multiple catecholamine-secreting head and neck paragangliomas and retroperitoneal pheochromocytomas, carotid body tumors and multiple extraadrenal pheochromocytomas succinate dehydrogenase complex B deficiency
Genetic determination	autosomal dominant
Prevalence	20p 100 of all paraganglioma
Function/system disorder	endocrinology
	neoplasia
Type	susceptibility factor

Gene product

Name

B subunit of the mitochondrial succinate dehydrogenase complex II

Mechanism(s)

Gene mutation	Chromosome rearrangement	Effect	Comments

various types
deletion			of exon 1 in Iberian Peninsular people, probably due to a founder effect

Remark(s)

hereditary susceptibility to familial paraganglioma syndromes is mainly due to mutations in one of six genes, including three of the four genes encoding the subunits of the mitochondrial succinate dehydrogenase complex II

Genotype/Phenotype correlations

features of SDHB mutation-associated disease include a later age of onset, extraadrenal (abdominal or thoracic) tumors, and a higher rate of malignant disease and possibly extraparaganglial neoplasias, including renal cell and thyroid carcinomas

In contrast, SDHD mutation carriers, in addition to head and neck paragangliomas, should be observed for multifocal tumors, infrequent malignancy, and the possibility of extraadrenal pheochromocytoma