Schizophrenia is a mental disorder characterized by an impaired ability to perceive reality. People with this condition experience hallucinations, delusions or disorganized speech and thought patterns.
Although researchers have uncovered evidence that schizophrenia genetic factors exist, the link between schizophrenia and genetics remains unclear. Is schizophrenia genetic? Environmental, psychological and social factors contribute to the development of schizophrenia, but genetics seem to play an important role as well.
Schizophrenia Genetic Risk Factors
Family and twin studies have been useful in determining schizophrenia genetic risk factors. In the general population, the possibility of developing schizophrenia is approximately 1 percent, according to the National Institute of Mental Health (NIMH) (2009). If you have a parent, brother or sister with schizophrenia, this figure increases to 10 percent.
A second degree relative with schizophrenia also increases a person’s risk of schizophrenia. Second degree relatives include aunts, uncles, cousins and grandparents. Schizophrenia genetic risks increase significantly when more than one family member has the disorder.
Twins and Schizophrenia Genetic Factors
Identical twins share the same genetic makeup. The NIMH (2009) reports that a twin has a 40 to 65 percent chance of developing schizophrenia if her twin is diagnosed with the disease. If schizophrenia was only linked with a particular gene or set of genes, then both twins would develop the disease.
Is Schizophrenia Genetic?
Although schizophrenia genetic factors are important, family studies imply that a complex mix of genetic and environmental factors influence the onset of schizophrenia. Some scientists believe that genes responsible for schizophrenia are only activated when a person is in a specific environment.
This supports the idea that both nature and nurture play a role in the development of schizophrenia. If an individual has a genetic predisposition to schizophrenia, she must also experience environmental stressors to actually develop the condition. So, overall, is schizophrenia genetic? The answer at present appears to be yes, but genetics alone don’t result in disease manifestation.
Tests for Schizophrenia Genetic Factors
No laboratory tests exist at this point for identifying schizophrenia genetic risk. Research has identified approximately a dozen schizophrenia genetic risk factors and evidence suggesting that people who develop schizophrenia have high rates of rare genetic mutations. These mutations can affect multiple genes, and could cause disruption of normal brain functions.
Chances are slim that a single gene will be identified as the cause of schizophrenia. It’s more likely that genetic factors, environment and personal brain chemistry all affect the development of schizophrenia.
National Institute of Mental Health. (2009). What causes Schizophrenia? Retrieved July 27, 2010, from http://www.nimh.nih.gov/health/publications/schizophrenia/what-causes-schizophrenia.shtml
Schizophrenia. (n.d.). The causes of schizophrenia. Retrieved July 7, 2010, from http://www.schizophrenia.com/hypo.php#genes
Varma, S. (1997). Genetics of schizophrenia and affective disorder – An overlap. Retrieved July 7, 2010, from http://priory.com/psych/genetics.htm