The report, published in the Journal of Biological Chemistry, said the findings may assist in the design of better drugs to treat the disorder, the NIH said Friday in a release.

Oxford Professor Amanda J. Law, a visiting scientist at the NIH, said the research expands on the discovery of genetic variations related to a gene that produces the protein Neuregulin 1.

Law and colleagues found that one of these DNA variations is associated with increased expression of a novel type of Neuregulin 1, called type 4, in the brains of patients with schizophrenia.

Other types of Neuregulin 1 proteins are involved in controlling how the brain develops and works in adults.

Researchers found that Neuregulin 1 type 4 is specifically expressed in the brain, unlike the other types of Neuregulin 1, and that the protein is 3.5 times more abundant in fetal brains. The report said the DNA changes may contribute to schizophrenia by modifying the development and wiring of the brain.