Gene mutations are responsible for at least 10 per cent of the non-familial cases of schizophrenia, researchers at Columbia University Medical Center have revealed.

The researchers said that scans of the genome of schizophrenics revealed the mutations that were present in the patients but not in their biological parents, who did not have the disease.

During the course of study, the researchers scanned the genome of 1,077 people which included 152 individuals with schizophrenia, 159 individuals without schizophrenia, and both of their biological parents for copy number mutations.

They found mutations, either a gain or loss of genes, in 15 individuals diagnosed with schizophrenia that were not present in the chromosomes of either biological unaffected parent.

The group said that only two of the mutations identified were found in persons without schizophrenia.

According to them, the participants in the study were from the European-origin Afrikaner population in South Africa, a genetically homogenous population that is ideal for genetic evaluation.

"We now know the cause of around 10 percent of the cases of sporadic schizophrenia," Nature magazine quoted Dr. Maria Karayiorgou, a professor of psychiatry who is one of the senior authors of the study, as saying.

"Schizophrenia is not as much of a 'big black box' as it used to be. The identification of these genes lets us know what brain development pathways are involved in disease onset, so that in the future we can look at better ways of treating this devastating disease," she added.