Analysis of the genetic pattern of individuals with schizophrenia has discovered numerous variations in DNA that increase the risk of developing the disease.

Significantly, many of these variations occur in genes that affect signaling among brain cells.

“When we compared the genomes of patients with schizophrenia to those of healthy subjects, we found variations in genes that regulate brain functions, several of which are already known to be perturbed in patients with this disorder,” said study leader Hakon Hakonarson, M.D., Ph.D., director of the Center for Applied Genomics at The Children’s Hospital of Philadelphia.

“Although much research remains to be done, detecting genes on specific pathways is a first step to identifying more specific targets for improved drug treatments.”

Researchers also found that the genes and signaling systems linked to schizophrenia had some overlap with those for autism and for attention-deficit hyperactivity disorder.

In fact, the current study found deletions in the same region of chromosome 16 as that found in a copy number variations (CNV) study of autism spectrum disorders that Hakonarson led in 2009.

“Although different brain regions may be affected in these different neuropsychiatric disorders, these overlaps suggest that there may be common features in their underlying pathogenesis,” said Hakonarson.

“These genes affect synaptic function, so deletions or duplications in those genes may alter how brain circuits are formed.”

The research appears in the Proceedings of the National Academy of Sciences, published online this week.

Hakonarson said future studies will investigate how these CNVs and other CNVs yet to be discovered may alter brain function.

Ultimately, he added, better understanding of signaling pathways in the brain may enable researchers to devise better drugs for schizophrenia, drugs that can selectively act on those biological pathways, with better efficacy and fewer side effects for patients.

Source: Children’s Hospital of Philadelphia