Schizophrenia and bipolar disorder both involve genetic mutations that increase the risk of developing the diseases, two new studies report.
The studies also found that the mental disorders share a large amount of genetic overlap.
In one of the studies, conducted at the University of Chicago, researchers reviewed 17 studies encompassing nearly 22,000 people, about half of which were schizophrenia patients. The study uncovered seven genetic variants, five of them new.
One in particular -- known as rs1625579 -- plays a key role in regulating brain cells. The results were published in Nature Genetics.
To scientists then duplicated the genome search with almost 30,000 other patients.
In the other study about patients with bipolar disorder, also published in Nature Genetics, researchers at Mount Sinai School of Medicine in New York first looked at the genomes of 7,481 people with the disorder and 9,250 healthy individuals. The study confirmed a strong link with the CACNA1C gene, which has also has been associated with schizophrenia.
Schizophrenia is characterized by hearing voices that are not real, as well as paranoid thinking and disorganized speech and thoughts. It affects about one percent of adults.
Bipolar disorder is characterized by drastic mood changes that swing from severe depression to euphoria, and it also affects about one percent of the population.
Researchers of both studies are hopeful that learning more about the affected pathways in the brain will lead to a better understanding of what causes schizophrenia and bipolar disorder, and that better drug treatments can be developed as a result.
