[Molecular Biological Background of Neurofibromatosis Type 2].

Neurofibromatosis type 2(NF2)is a hereditary tumor syndrome characterized by bilateral acoustic nerve tumors, multiple schwannomas, and multiple meningiomas. About half of the patients develop familial onset through an autosomal dominant mode of inheritance. The causative gene of NF2 is the NF2 gene, and those who have a germline mutation of the said gene invariably develop the disease. On the other hand, about half of NF2 patients are sporadic cases. It is thought that the somatic mosaic of the NF2 gene is involved in most of the sporadic cases, in which germline mutation of NF2 is not detected. It is becoming clear that the clinical features, such as the life and functional prognoses of NF2 patients, differ depending on the genotype of the causative gene.