Genomic alterations in human glioma cell lines detected by restriction landmark genomic scanning.

Restriction landmark genomic scanning (RLGS) is a 2-dimensional gel analysis capable of detecting amplifications, deletions and rearrangements in genomic DNA. Using RLGS, we examined genomic DNA from each of 6 human-derived malignant glioma cell lines and from normal brain tissue samples. RLGS allows us to screen genomic DNAs as approximately 2,000 landmark sites in one procedure without any polymorphic markers. The resulting 2,000 spots in tumor samples were compared with those in normal brain. Six spots common to 5 of the 6 cell lines showed intensified signal, suggesting amplification of a tumor-specific DNA fragment. In addition, 25 spots common to 5 of the 6 lines showed a decrease in signal intensity, conversely indicating allelic loss of homozygous deletion. These results imply the existence of consistent genetic alterations in human glioma.