Nature has been pitted against nurture for centuries. People have always pondered the question of whether human behaviour is primarily dictated by genetic hard-wiring or by our experiences and environmental factors.
The debate has lasted so long because we know comparatively little about the functioning of the human brain. As a result, disorders of the brain have been the subject of much conjecture, discussion and even controversy.
Even today, the causes of many psychiatric illnesses are basically unknown. Researchers are working hard to determine just how much of a role our genes play in our mental health and how often brain disorders are the result of a neglected youth or stressful life circumstances.
As is often the case in life, the answer is proving to be more gray than black and white. While mapping the human genome, researchers are pinpointing genes that appear to be involved in psychiatric illnesses such as schizophrenia, bipolar disorder and depression.
This is not surprising to doctors since the illnesses often appear to affect more than one member of the same family and more commonly affect biological relatives than adopted ones.
On the other hand, research also shows that stressful life circumstances or severe neglect can work to physically change the make-up of a person’s brain and make them more susceptible to mental illness in the future. Likewise, some people whose genes may point to a susceptibility to mental illness, never exhibit any symptoms.
All of this information will be used by doctors to create more tailored treatments for many psychiatric illnesses. It is now being discovered, for example, that schizophrenia and bipolar disorder are not always as distinct as was once believed. They may often share some genes and their specific clinical symptoms may depend on which of the many contributing genes are present in a particular individual.
In recent years a number of studies have begun to identify specific genes involved in a variety of psychiatric disorders. These kinds of discoveries may lead to more streamlined treatments in the future that will depend on which genes are affected in each patient.
While the role of genetics in psychiatry is still being actively explored, it is becoming increasingly clear that our genes influence everything from our personality traits to specific psychiatric disorders.
In the end, the age-old debate of nature vs. nurture will be reframed. Our genes may predispose us toward a certain psychological profile, but our circumstances and the choices we make in life can either switch those genes on or leave them dormant. Future treatment will reflect this more sophisticated understanding of the relationship between nature and nurture.
Dr. Latimer is president of Okanagan Clinical Trials and an Okanagan psychiatrist.