Mental Illness and Genetics

Mental Illness

Mental health conditions can range from mild depression or anxiety, to severe mental illnesses like schizophrenia or bipolar disorder, or anywhere in between. A mental illness can have a major impact on your life, so it’s understandable if you’re worried about developing one or passing one on to your children. Maybe you have a close family member who has a mental illness that you’ve heard “runs in families” and you’re wondering – is mental illness genetic?

Is Mental Illness Genetic?

Mental health conditions are usually the result of several different factors. So, while there is “no single genetic switch that when flipped causes a mental disorder,” genetic factors can play a role in the development of a mental illness. 

Dr. Jimmy N. Avari, Associate Professor of Clinical Psychiatry at Weill Cornell Medical College and Assistant Attending Psychiatrist at New York-Presbyterian Westchester Behavioral Health Center, says that “genes are clearly an important part of many psychiatric illnesses.”

Many studies that have been done on twins confirm this. Identical twins share 100% of their DNA and fraternal twins share 50% of their DNA, so there should be no major biological differences between them. Researchers can also assume that when twins are raised in the same house by the same parents, there won’t be any major environmental differences. This controlled environment means that if the twins being studied both develop a certain condition, it may be due to genetics. 

Dr. Avari says:

“Twin studies of major depressive disorder have showed that if one twin has the illness, a fraternal twin has an increased likelihood of developing the disorder and an identical twin’s likelihood is even higher.”

This is strong evidence for the role of genetics in mental illness.

What Causes Mental Illness?

According to research analysis from the National Institute of Mental Health (NIH), mental illness is usually caused by a combination of four main factors:


Genetics can play a role in mental illness, but having a family member with a mental illness doesn’t automatically mean you’ll develop one yourself.

Your risk also depends on how many and which family members you have who have experienced mental illness. For example, schizophrenia occurs in 1% of the general population – but it occurs in 10% of people who have a first-degree relative (like a parent or sibling) with schizophrenia. But keep in mind that even if you have a close family member with mental illness, that doesn’t mean you will definitely develop a mental illness yourself. Having a close family member with a condition is only a risk factor, not a direct cause.

So while you may have a genetic vulnerability that may predispose you to developing a mental illness, other factors play a role, too.


Biological factors can include anything that has negative effects on the body. These can be internal or external and might include abnormal functioning of nerve pathways, chemical imbalances in the brain, brain injury, prenatal damage, chronic illness, infections or substance abuse.

Environmental Factors

Certain things in your environment can contribute to the development of mental illness. These can be things in your home (whether that’s your current home or the home you grew up in) or the country, city or neighborhood you live in. This includes things like crime, racism, poverty, poor housing, pollution or toxins.

Psychological Factors

Psychological factors that can contribute to mental illness include:

  • Adverse childhood experiences (ACEs) like experiencing or seeing abuse, neglect or household dysfunction
  • Experiencing stressful situations like the death of a loved one, a divorce, job loss or financial or relationship problems
  • Trauma
  • Low self-esteem
  • Feelings of loneliness or isolation

How To Reduce Your Risk of Developing Mental Illness

Even if your genetics put you at greater risk of a mental illness, that doesn’t mean you’re doomed to develop one. Staying vigilant for symptoms, seeking professional help and taking care of both your physical and mental health will greatly reduce your risk.

Get Better Sleep

Research has linked poor sleep with mental health conditions. Getting enough high-quality sleep can reduce your risk of mental illness

Get Enough Exercise

Staying physically active can help you to prevent and manage many physical and mental health issues. Exercise can improve your mental health by:

  • Reducing stress and anxiety levels
  • Boosting your mood and self-esteem
  • Improving cognitive function
  • Improving your quantity and quality of sleep
  • Increasing social interaction and feelings of connectedness

Eat a Healthy Diet 

A healthy diet – one that includes a variety of fruits, vegetables and whole grains, and limits processed foods, saturated fats, and refined sugars – is, along with exercise, one of the easiest ways to improve and maintain health and wellbeing. 

Learn To Manage Stress

We all have stress, but when you let it get out of control, that’s when it becomes a problem. There are many ways to manage stress. The key is finding what works for you. Some stress-relieving techniques include:

  • Exercise
  • Meditation
  • Yoga
  • Hobbies
  • Spending time in nature
  • Socializing with friends and family

Limit Substance Use

Using substances like alcohol or drugs can often have a negative impact, especially if you’re using substances to excess. It can also be a major problem if you take medication for an existing mental health condition, since most medications have interactions with alcohol and other drugs.

Build Up Your Support System

Having a strong support system is one of the most important factors that contribute to good mental health and overall wellbeing. Whether it’s your biological family or a circle of good friends, having a few people you know you can trust and turn to in a time of need is essential. If you feel like your current support system is weak (or nonexistent), don’t give up. Get involved in your community via volunteering or other activities and go out and meet your people. 

Support for Mental Illness in Region Five

Are you worried about developing a mental illness? Seeing a mental health professional regularly is one of the best ways to notice early symptoms and prevent or manage any problems that may come up.

If you live in the Greater Tidewater Hampton Roads Area of Virginia, also known as coastal, southeastern Virginia, you can always find help at Region Five. Region Five is your primary point of entry for affordable and accessible mental health help.

If you live in Region Five, make an appointment for same-day access to services at your local Region Five community services board. If you live in another area of Virginia, find your local CSB here.

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