That discovery could help improve insight into childhood brain tumors, says an international team of scientists.

"Our findings suggest that brain tumors arising in different regions may be genetically distinct as a consequence of their unique cellular origins. This is yet another factor we need to consider when trying to understand how pediatric brain tumors form," study senior author Dr. David H. Gutmann, professor of neurology at Washington University School of Medicine in St. Louis, said in a prepared statement.

He led six laboratories in a detailed genetic analysis of pilocytic astrocytoma, the most common kind of childhood brain tumor.

"We were hoping to identify genes that contribute to the formation of these tumors and find indicators that might help us predict which tumors will be relatively well-behaved and which will be more aggressive," said Gutmann, who is also co-director of the neuro-oncology program at the Siteman Cancer Center.

"When we looked at gene activity levels in the tumors as a function of brain location ... a very interesting pattern began to emerge," he said.

The researchers found that tumors that develop in different parts of the brain retain distinct patterns of gene expression. This suggests that genetic fingerprints can be used to pinpoint the likely origins of brain tumors.

The study is in the Feb. 1 issue of the journal Cancer Research.

"There's been a movement in recent years to link normal brain development to pediatric neuro-oncology, and these findings affirm that as a necessary approach," Gutmann said. "We won't fully understand the causes of pediatric brain tumors until we consider them in the context of factors that shape the development and specialization of different brain regions."