Chromosome studies in two human brain tumors.

The cytogenetic findings based on G- and C-banding in two human brain tumors (a meningioma and an astrocytoma) are reported. Both tumors were characterized by hypodiploid modal numbers (45 and 40 chromosomes, respectively), chromosome 22 abnormalities, and the presence of several markers. This observation supports the hypothesis of the association of No. 22 chromosome abnormalities with tumors of the brain.