Mental Illness Heredity: Does Mental Illness Run in Family?

People tend to believe that mental illnesses are inherited and if one person in a family has got some mental illness others are more likely to get it at some point. Mental illness is a very wide term and hence there cannot be an answer true for every condition. But, it is important to understand whether mental illnesses can be inherited or not. The information is even more important for people who have a family member with a mental illness and individuals with mental illness planning to start a family.

Can Mental Illness be Inherited? – Quick Answer!

There are hundreds of conditions that come under the umbrella term of mental illness. Some of these mental illnesses are hereditary in nature. But, no mental illness is 100% based on inheritance or genetic cause.

Many environmental factors are also responsible for mental illnesses despite the presence or absence of genetic reasons. This simply means that a person may get a mental illness due to other environmental factors even without the genetic factors for mental illness and a person with such gene may never develop a mental illness.

Having said that, certain mental disorders have a very high degree of heritability. In such cases, the possibility of getting the mental illness when someone else in family has it, increases significantly. Further, certain genetic mutations or polymorphism increases the chance of an individual to get mental illness without any family history of such mental illness.

In a nutshell, some mental illnesses can be inherited but the probability of getting a mental illness is not completely based on inheritance. The incidence of mental illnesses depends on various environmental factors too.

Environmental Factors Contributing to Mental Illness

As discussed above, genetics is not the only factor contributing to mental illnesses. There are many environmental factors that can contribute to mental illnesses. We can broadly classify those environmental factors into two categories – physical environmental factors and social environmental factors.

Physical environmental factors that may contribute to a mental illness include, but are not limited to the following –

• Poor nutrition
• Sleep deprivation
• Pollution
• Substance abuse
• Exposure to toxins during childhood
• Hazardous condition at work
• Extreme weather conditions
• Lack of sunlight

Social environmental factors that may contribute to mental illness include, but are not limited to the following –

• Social stigma (as for disability or LGBTQ community)
• History of abuse as a child
• Family discord or such traumatic experience during childhood
• Early loss of parents or loss of someone very close
• Poverty
• Lack of meaningful job, work, or hobby
• Toxic relationships
• Lack of self-care

Mental Illnesses with High Degrees of Heritability

Though no mental illness is based 100% on heritability some of them have significantly higher degrees of heritability.

Following table lists the estimated chances of heritability of schizophrenia and bipolar-disorder.

Here, we are providing a small list of common mental illnesses with high degrees of heritability.

1. Bipolar Disorder

It is considered the most highly genetically inherited mental illness. 70-90% of cases of bipolar disorder are attributed to inheritance rather than other environmental causes. Having first-degree relatives with bipolar disorder drastically increases the chance of developing bipolar disorder.

2. Schizophrenia

While the general population has a 1% risk of getting schizophrenia someone having a first-degree relative viz. parents or siblings with schizophrenia is at 10% risk of being schizophrenic. If both the parents are diagnosed with schizophrenia, their children have a almost 50% chance of getting the mental condition. The exact cause of schizophrenia is still unknown but genetics plays an important role in the development of schizophrenia.

3. Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a neuro-developmental disorder usually present from birth. Specific genes have been implicated with different disorders under ASD. According to a 2018 study, around 74-93% of ASD risk is inheritable. If the first child of parents is born with ASD the second child is 2-8% more likely to be born with ASD.

4. Attention Deficit Hyperactivity Disorder

Around 75% of ADHD cases in children and 35-75% cases in adults are determined by genetics. Siblings of someone with ADHD are four times more likely to develop ADHD as compared to those with no siblings with ADHD.

5. Major Depressive Disorder

Someone with a parent or twin with major depressive disorder is 40% more likely to get major depressive disorder as compared to someone with no close relative with MDD.

Looking After Your Mental Health

While everybody needs to take care of their mental health, you will want to be a little more cautious if someone in your blood relation has a mental illness. You should know that there’s no way to prevent the development of mental illness if something out of your control is causing it. But, you can take care of your mental health and make sure that no external factor catalyzes the development of mental illness.

Here are some tips that can help you to support your mental wellness. Try to incorporate these habits into your routine.

• Keep a Journal – Writing about your day viz. how you spent your day, how did you feel, etc. is considered a very good habit for mental health. Writing down the problems you face can help you to think clearly. Your journal can also help you track your mood and find the early signs of mental issues like stress and depression. Keeping a journal is a habit with multiple benefits.
• Get 7-9 hours of sleep every night – Lack of sleep can be the trigger to many mental health issues. So, be sure to take the recommended amount of night sleep without disturbances.
• Speak about your feelings to someone you trust – It is even more necessary when you are having negative thoughts and feelings. When a person keeps her feelings to herself she is more likely to overthink the issue and this may be a precursor to mental illnesses. So, make a few trusted friends and talk to them about your thoughts and feelings whenever you need them.
• Spend time with a loved one – Staying happy and cheerful is one of the best ways of keeping many mental health issues at bay. So, try to spend time with your loved ones as much and as often as possible. Share happiness and laughter.
• Get Regular Exercise – You must have heard that a healthy body is a home to a healthy mind. So, one of the best tips to keep your mind healthy is to keep your body fit. Include physical exercise in your daily routine to keep yourself physically and mentally healthy.
• Practice Meditation – More and more research and studies are confirming that meditation plays a very important role in keeping the mind healthy. Every individual must take a few minutes to practice meditation daily.
• Be Mindful – Mindfulness is considered one of the forms of meditation that you keep on doing the whole day. It is the practice of keeping your attention here and now. Being mindful has unthinkable benefits for our mental health.