A complex rearrangement of chromosome 7 in human astrocytoma.

Chromosome 7 is a frequent site of cytogenetic aberrations in human astrocytomas. One region that is often targeted in human astrocytomas is on 7p. The U251 human glioblastoma cell line has a region of gain of genetic material on 7p similar to that seen in human astrocytomas. We used several cytogenetic techniques to study chromosome 7 in U251 cells and identified a complex rearrangement that accounts for gain of chromosome 7 genetic material in the cell line. The characteristic rearrangement suggests a mechanism leading to 7p gain in primary grade IV astrocytomas.