Largest-Ever Study Finds Genetic Markers for Schizophrenia
A collaboration of more than 100 scientists from several countries has identified 108 genetic markers linked to schizophrenia, according to research recently published in the journal Nature.
The study comprised the largest effort ever to genetically map schizophrenia; previous efforts to find solid genetic links to the serious mental illness have yielded no significant results. Eighty-three of the 108 genes identified as part of this latest research effort have never before been connected to schizophrenia.
The research involved more than 150,000 participants, 37,000 of whom had been diagnosed with schizophrenia. The teams of scientists mapped the genetic codes of each of the 150,000 study participants in order to isolate variations that were more apparent among the subjects with the illness.
Identifying individual genetic links to illnesses like schizophrenia takes a long time, because the influence of each single gene is quite small. However, gradually identifying large numbers of genes that contribute to the risk of schizophrenia gives researchers a much clearer picture of the biological systems that play the largest role in this disorder.
Schizophrenia and the Immune System
One of the physiological systems that the new research has linked more strongly to schizophrenia is the immune system. Previous research has hinted at a connection between schizophrenia and the immune system, and many scientists are encouraged by the apparent confirmation of this previous evidence.
Earlier studies have found that schizophrenia is more likely to affect families with autoimmune disorders. A greater incidence of schizophrenia has also been linked to children whose mothers catch certain viral infections during the second trimester of pregnancy.
Findings such as these allow future research to focus on increasingly narrow fields of possibility and get ever closer to zeroing in on the cause of schizophrenia. Isolating the source of the illness will help scientists identify better ways to treat the disorder as well as prevent the disorder from appearing.
Greater Risk With More Genetic Markers
Due to the fact that each of the identified genes has a relatively limited effect on its own, the researchers estimate that most people who are free of the illness have 20 to 30 of the genetic markers that have been linked to schizophrenia.
Nevertheless, the research did show that people with a significantly higher number of the genetic markers had a notably higher risk of schizophrenia. The participants with the highest number of genetic markers were 15 times more likely to have schizophrenia than those with a low percentage of the 108 genetic markers.
These figures have some scientists hopeful that they may be able to develop a genetic test for schizophrenia. Such a test could potentially be administered to young people well before any symptoms of the disease appear, and give them the option of early treatment.
However, the researchers add that much more investigation is required before that becomes possible. Although people with a significant number of genetic markers were more likely to have schizophrenia, they were still more likely to be free of the illness than to be afflicted by it.
This suggests that there is a great deal left to discover about the source of this mental illness. There may be more genetic factors that remain unidentified, or there may be situational factors that have to occur before the illness is triggered in people who are at the greatest risk.
Fighting a Costly Illness
Nevertheless, the progress demonstrated by this study gives experts hope that they are closer to unlocking the puzzle of schizophrenia. This serious mental disorder can be socially, economically and personally debilitating. It’s also an expensive illness from a public standpoint, costing the United States approximately $60 billion each year in treatment and other expenses related to the disruptive nature of the illness.