One of the longest running debates in the field of psychology is whether mental illness has a genetic or an environmental basis (‘Nature versus Nurture’). There has been evidence supporting both theories throughout the years, so most people agree that mental illness is caused by a combination of both kinds of factors.
Recent research has shown that there are some genetic similarities in people who have certain mental health conditions.
The new study examined the genetic information of people with autism, Attention-Deficit Hyperactivity Disorder (ADHD), major depression, schizophrenia, and bipolar disorder. The researchers found that the people in the study were more likely to possess certain genes than healthy people were.
Their findings were supported by the similarity of some of the keys symptoms presented by people with schizophrenia, major depression, and bipolar disorder. People with ADHD and autism (many of whom are diagnosed before age 18) also display some common behavioral symptoms.
It is rather common for an individual with a mental health illness to have close relatives who also have some kind of mental health condition. A person with an anxiety-related illness, for instance, is more likely than a healthy person to have a cousin or sibling with a disorder like depression or schizophrenia.
An article from Yahoo! News explains the research findings in greater detail: