Multiple endocrine neoplasia type 1 (MEN1, OMIM #131100) is a genetic disease caused by pathogenic variants in the MEN1<\/em> gene. It mainly leads to a predisposition to parathyroid tumors with primary hyperparathyroidism (PHPT), pancreatic islet cell tumors, and adenohypophysis (anterior pituitary neuroendocrine tumors, PitNET). All in all, the MEN1 tumor spectrum includes more than 20 endocrine and non-endocrine tumors, which may occur in different combinations.<\/p>\n<\/div> Synonym:<\/p>\n<\/div><\/div><\/div> Wermer syndrome<\/p>\n<\/div><\/div><\/div><\/div> Gene:<\/p>\n<\/div><\/div><\/div> MEN1<\/i><\/p>\n<\/div><\/div><\/div><\/div> Gen\u00ade product:<\/p>\n<\/div><\/div><\/div> Menin protein<\/p>\n<\/div><\/div><\/div><\/div> Function:<\/p>\n<\/div><\/div><\/div> Presumably functions to regulate the cell cycle, transcription, and to maintain genomic stability<\/p>\n<\/div><\/div><\/div><\/div> Pattern of inheritance:<\/p>\n<\/div><\/div><\/div> Autosomal dominant; around 10% de novo mutations<\/span><\/p>\n<\/div><\/div><\/div><\/div> Prevalence:<\/p>\n<\/div><\/div><\/div> 1:20.000 \u2013 1:40.000<\/p>\n<\/div><\/div><\/div><\/div> Genotype-phenotype correlation:<\/p>\n<\/div><\/div><\/div> unknown<\/p>\n<\/div><\/div><\/div><\/div> Penetrance:<\/p>\n<\/div><\/div><\/div> With regard to all clinical manifestations: over 50% at age 20 and over 95% at age 40<\/p>\n<\/div><\/div><\/div><\/div><\/div><\/div>