GENETICS Brain tumors

NF-1:
von Recklinghausen, chromosome 17q11.2, 1/3,500 live births, NF1 encodes neurofibromin, autosomal dominant, 50% germline, 50% new mutations, peripheral nerve sheath neurofibromas, café au lait spots, optic and intracranial gliomas, and  bone abnormalities.

NF-2:
chromosome 22, 1/50,000 live births, NF2 encodes merlin, autosomal dominant, bilateral acoustic neuromas, gliomas, ependymomas, and meningiomas.

von Hippel-Lindau:
chromosome 3, autosomal dominant, renal
clear cell carcinoma, pheochromocytoma, hemangioblastoma, pancreatic tumors, and renal cysts.

Tuberous sclerosis (Bourneville’s disease): TSC1 on chromosome  9, TSC2 on chromosome 16, autosomal dominant, subependymal giant cell astrocytoma, retinal and rectal hamartomas.

Retinoblastoma:
Rb tumor suppressor gene, chromosome 13.

Li-Fraumeni syndrome:
germline p53 mutation = breast, sarcoma,
and brain CA.

Turcot’s syndrome:
primary brain tumors with colorectal CA.

Neuroblastoma:
N-myc amplication commonly seen and serves as a prognostic factor.