I have been asked this frequently over the last month, and it can be a difficult concept to explain. Put briefly, mental illness is thought to be due to a combination of your genetic makeup and your environments affect on your developing brain. There is a continual ‘Nuture vs Nature’ debate about mental illness. All mental illnesses (Schizophrenia. Depression, Bipolar Disorder, Anxiety Disorders, Substance Disorders etc) have been found to have genetic links. This means that ‘part’ of the illness is most likely inherited. It is not one specific gene that causes mental illness but is thought to be a cluster of genes in specific patterns which predispose to the development of the illness.

This results in what we call a ‘genetic vuneralbility’ Even if a person has that cluster of genes – it is not definite that they would develop a mental illness. Certain environmental stressors both internal and external stressors interact with your own genetic venerability – and may encourage the development of an mental illness.

Some environmental causes

– Loss of a parent at a young age

– Abuse – Sexual / Physical / Emotional

– Exposure to stress/ substances while in-utero. ( i.e.. while your mother was pregnant)

– Brain injury – Trauma

– Chronic medical disease – heart disease, cancer etc

– Substance Abuse – Alcohol, Cannabis, Codeine, Street drugs

– Traumatic event – natural disasters/ events where your life or someone else’s was at risk Here is a short easy to understand youtube video which explains this concept very briefly. He refers to the stress- diathesis model – similar to the gene-enviromental interaction as I described above.https://youtube.com/watch?v=1ZmSDpZAdNQ%3Ffeature%3Dplayer_detailpageframeborder%3D0allowfullscreen