P16 DELETION AND MUTATION ANALYSIS IN HUMAN BRAIN-TUMORS

We screened human primary and recurrent malignant glioma, juvenile pil ocytic astrocytoma, medulloblastoma, and meningioma tissue specimens f or alterations in p16 gene structure. Single strand conformation polym orphism (SSCP) analysis was used to screen for point mutations, and a quantitative polymerase chain reaction-based assay was used to screen for homozygous gene deletions. In malignant glioma specimens, homozygo us p16 gene deletions were significantly more common in high-grade tum ors than in low-grade gliomas. Point mutations causing alteration in p redicted protein structure were not detected. Medulloblastomas showed rare homozygous deletions and no point mutations. No mutations were de tected in meningiomas.