Many people consider suicide to be taboo, and it’s a subject that is often avoided. However, the more we understand the reasoning behind why some people are pressed to commit suicide, the better equipped we may be to offer support and guidance for treatment. Interestingly, certain lifestyles and various environmental factors might be able to influence a specific gene linked to stress, which could increase suicide risk in adults and even adolescents.
In a new study, researchers from Uppsala University, Karolinska Institutet, and Umeå University investigated the link between epigenetics and the severity of suicide attempts. They also assessed the pattern of epigenetic marks in adolescents at high-risk for mental illness.
Previously, we covered the well-known stress pathway – the hypothalamic-pituitary-adrenal (HPA) axis – and how epigenetics influences panic disorder via excitability of this channel. Other research suggests that an overactive stress system in people is related to a higher risk of suicide.
In the current study published in EBioMedicine, epigenetic changes of several HPA-axis coupled genes were assessed, including the corticotropin releasing hormone (CRH). The team looked at a popular epigenetic mechanism which suppresses gene expression, known as DNA methylation. It’s characterized by the addition of a CH3 group on to certain areas of DNA.
They examined 88 people who had attempted suicide and divided the participants into high- and low-risk groups. Blood samples were collected and the scientists measured the amount of DNA methylation in several genes related to the stress system.
“Two CRH-associated CpG sites were significantly hypomethylated in the high-risk group of suicide attempters,” the researchers reported. This suggested that a reduction of DNA methylation in this location might be an indicator of a person’s potential to commit suicide.
“Since psychiatric illness is a serious and growing public health problem, it’s important that we take early signs of psychiatric illness and suicidal behavior into consideration in suicide prevention,” said the head of the study, Jussi Jokinen, who is also a professor in psychiatry at Umeå University.
They also aimed to identify whether the epigenetic changes could also be found in adolescents who were much more likely to develop a psychiatric illness than others. They analyzed over 200 adolescents combined between the ages of 14 to 17 in two other cohort studies.
They discovered that children with a high risk for psychiatric illness had hypermethylation, or an increase of methylation, of the CRH-associated sites on their DNA. This was in contrast to hypomethylation seen in the group of high-risk suicide attempters.
“Our environment affects our genetic expression, which is usually referred to as epigenetic change. Even if we aren’t able to draw distinct parallels between the findings in these cohort studies, our results still point towards the importance of an optimal regulation of the stress system for psychiatric illness.”
Psychiatrists believe that over 90 percent of suicide cases are a result of a mental disorder and many of these people do not receive treatment for their illness. It’s a pressing matter, especially since the mental health of youth continues to worsen and most youths are unable to receive the help they need.
It’s intriguing to consider how someone’s environment or lifestyle might impact gene expression related to the stress system and how this might give us a glimpse into and individual’s possible suicide risk. However, more research should be conducted before we can draw any definite conclusions.
Overall, the researchers found that epigenetic effects on the body’s stress-system are associated with psychiatric illness and suicidal behavior, but the epigenetic signature varied between adults and adolescents. This evidence can guide new studies towards potential therapies and contribute to our efforts to help those who need it most.
Source: Jokinen, J et al. (2017). Epigenetic Changes in the CRH Gene are Related to Severity of Suicide Attempt and a General Psychiatric Risk Score in Adolescents. EBioMedicine, DOI: 10.1016/j.ebiom.2017.12.018.
Reference: Umea University. Genetic changes caused by environmental factors linked to suicide risk. Umea University. 18 Dec 2017. Web.