Tumor-specific DNA sequences in human gliomas

Utilizing the technique of hydroxyapatite chromatography, normal cellular DNAs were used to recycle off the repeat or normal sequences found in [3H]DNA copied off 70S RNA from malignant astrocytomas. The recycled [3H]DNA were then used to hybridize against DNAs from normal human brain tissues and DNAs from malignant astrocytomas or Grade IV astrocytomas. The results indicated the presence of tumor-specific DNA sequences in malignant astrocytomas, absent in normal brain tissues. The percentages were 88% and 7%, respectively. When recycled medulloblastoma 70S[3H]DNA probes were utilized against DNA'S FROM Grade IV astrocytomas and from normal brain, similar results were obtained. The respective percentages of hybridization were 67% and 7%. Thus it would appear that malignant gliomas contain tumor-specific DNA sequences which are not found in normal brain tissues.