Methods: Frequent homozygous deletions of the CDKN2 gene were detected in 81 cases of brain and spinal cord tumor resection specimens by PCR method.

• 方法：采用聚合酶链反应(PCR)对81例脑、脊髓肿瘤手术标本中CDKN2基因的丢失情况进行了检测。