The Genetics of Mental Illness

Researchers have long believed that genetics put some people at higher risk for mental illness than others, but exactly which genes are involved has remained a mystery. Even very large studies have come up with relatively few insights into the genetics of mental illness. But a study published last week in The Lancet is shedding some light on the connection between genetics and mental illness. The study is the largest mental illness study done to date, and used genetic data from over 60,000 people of European ancestry. The scientists, led by Dr. Jordan Smoller from the Massachusetts General Hospital in Boston, looked at five different forms of mental illness: autism spectrum disorder, bipolar disorder, attention deficit-hyperactivity disorder, major depression disorder, and schizophrenia. They found four different genetic associations with mental illness in general, and surprisingly they discovered that three of the four associations were involved in all five conditions. This means that the same genetic variants involved in depression may also be involved in schizophrenia.  This genetic similarity between different forms of mental illness was suspected from previous studies in which twins would have different forms of mental illness. Another interesting aspect of this new study was the importance of calcium channels. Calcium is important for muscle contractions and heart beats, and calcium channels are gates that let calcium in and out of our cells. Two of the four genetic variants that the researchers found occur in genes that encode these calcium channels, suggesting that calcium channels may also be important for mental health. Sometimes research discoveries seem too removed from our day-to-day life to matter.  Yet this new insight into calcium channels could lead to new treatments, and new treatments would mean good news for millions.  During the course of this year, it is estimated that one in ten of us will suffer from a mood disorder, such as depression or bipolar disorder.  If it’s not you, it may be someone you know.  That makes this study pretty exciting for us all.

This graph shows the prevalence of different forms of mental illness in US adults in any given year. Statistics are from NIMH.

 SNPwatch gives you the latest news about research linking various traits and conditions to individual genetic variations. These studies are exciting because they offer a glimpse into how genetics may affect our bodies and health; but in most cases, more work is needed before this research can provide information of value to individuals. For that reason it is important to remember that like all information we provide, the studies we describe in SNPwatch are for research and educational purposes only. SNPwatch is not intended to be a substitute for professional medical advice; you should always seek the advice of your physician or other appropriate healthcare professional with any questions you may have regarding diagnosis, cure, treatment or prevention of any disease or other medical condition.
  • DCWilson

    And what about rs1024582, another one of the four key SNPs mentioned in the Lancet paper? Is it the A or G allele that is associated with the risk factor for mental illness?

    The amazing thing about the Lancet study, which I read the day it came out, is that it clearly demonstrates the significance of the four loci and then declines to state which allele is is associated with the risk state at every one.

  • Aaron

    Where can this and all other SNP results in my account?
    It seems like many blogs mention SNPs that aren’t in my account.
    It would be nice if there were a collection of them all from blogs.
    Like along with the disease risk, carrier status, drug response, there would be another section with misc findings that are talked about in blogs.

    • ScottH

      Aaron, If you are logged into your 23andMe account while looking at this post you will see your results for the SNPs identified in the paper. If not, you can click on the “log-in” link where we call out the SNP. You can then see your genotype for the SNP.

  • MarktheArch

    Is there any marker that my 23and Me profile evaluated to see if I, personally, have a predisposition to one of these mental illness? I don’t think I do, and neither do I. (Seriously wondering but not worried here). My kids and wife have diagnosed me with ADHD, and I am suspicious.

    • MarkTheArch

      I guess I have to answer myself here. 23andMe has verified I am of Western European Ancestry and has also verified my risk of any mental illness is that same as expected for others with Eastern European.
      IE., 23andMe has told me nothing I didn’t already know.

    • ScottH

      We do have a preliminary reports that looks at your genetic risk for ADHD, Bipolar Disorder, and schizophrenia. You can look at what your genetic risk for the disease is for each of these conditions. The reports also detail the studies upon which these are based.

  • LMar

    I suspect mental illness in my family. Both parents say they have no clue if there is. Yet, not only do they both have diagnosable (but are undiagnosed) mental illnesses, I have been diagnosed.

  • Sieglinde

    Mental illness
    Is mental illness a genetically inherited problem or environmentally induced?
    This question can only be answered if we test first the fetus, then after birth, and again at the age of ten and at last as an adult.
    That abuse is causing gene alteration is documented in these reports:
    “Increased methylation of glucocorticoid receptor gene (NR3C1) in adults with a history of childhood maltreatment: a link with the severity and type of trauma”
    Biomarker for PTSD and Why PTSD Is So Difficult to Treat
    Scientists Identify Depression and Anxiety Biomarker in Youths
    Childhood Adversity Increases Risk for Depression and Chronic Inflammation
    Depression Linked to Telomere Enzyme, Aging, Chronic Disease
    My suspicion is mental illness is the result of genetic alteration, caused by neglect (also not being breast fed), physical and mental abuse and sexual abuse/rape: meaning, an abused child grows up with lack of oxytocin, too much adrenalin and low serotonin, just to mention a few.
    The consequences are: anxiety, depression, and/or PTSD and many more permanent psychological disorders.
    What good does it do if we know that genes are altered if we cannot deliver a cure?
    Humanity would benefit on a great scale if we aim for preventing gene methylation, so we don’t pass on faulty genes to the next generation.
    Will 23andme take on the challenge to prove or disprove, if mental illness is man-made and the reason for gene alteration?

    • relivschmidt

      Finding the origin is important but while we wait let’s treat with products that flip the off switch on bad genes. Lunasin peptides do this. Reliv has it. I share it with others.

  • tommyc

    In response to Sieglinde; it has been/is mom and dad’s experience with our children that even a household totally void of violence and abuse of any kind, genetics by itself has played a dominate role in our children’s upbringing. Their convoluted perceptions about themselves, the world around them, etc… However, that said, mom and dad now feel that if our children had been all born a little later, (5-8 years in general) we could have been involved in parenting classes targeted to our children’s particular genetic challenges that could have greatly alleviated many or their troubling misconceptions.

  • I did not know that calcium channel is responsible for mental health, yes this is essential component for initiation of muscle contraction and for the conductive system of our heart.This study helps us to do better for the people with mental illness or psychological disorder.

  • Tiffany Lee Brown

    I don’t suppose anyone knows of a third-party site that will let me find this information in my 23andme raw data, similar to finding out about methylation and detox profiles on geneticgenie? For Entertainment Purposes Only, of course!