How Genes Alter Your Mental Health
We are all made up of genes, the genetic code that makes us who we are. Without variety in this code, we would all be the same. Being the same may make certain processes easier, for example understanding each others’ behaviours and tendencies, but where is the fun in that? We each have our own unique set of skills, talents, habits and reactions, what causes these differences? It all comes down to a combination of past experiences and more importantly our genetics, this leads to an age-old concept of nature vs. nurture.
Which genes are responsible for these changes
We have all heard of various mental illnesses, including depression, anxiety and schizophrenia. It is hard to decipher where these conditions stem from and why certain people are more greatly affected. In recent years, studies have been completed and certain patterns have been identified.
Recent studies
In 2015, a study looked at mental illness in twins and concluded that the RBFOX1 gene has the potential to make someone more susceptible to anxiety. Other suggested genes include:
- DRD4 (Dopamine receptor D4),
2. HTR1A (5-hydroxy-tryptamine recepter 1A),
3. MAOA (Monoamine oxidase A)
4. PCLO (Piccolo presynaptic cytomatrix protein)
Both dopamine and serotonin receptors have been suggested and it is believed that depression is a result of an imbalance in serotonin and dopamine levels.
Measuring hormones
In the past, it was very difficult to measure these hormones accurately however we have since made significant breakthroughs in the field. Researchers at the MAYO clinic have concluded that through using deep brain stimulations, levels of serotonin in our brains can be detected. This tool is known as a WINCS or a Wireless Instantaneous Neurotransmitter Concentration System. In the case of dopamine, doctors can measure the density of our dopamine transporters which positively correlate with dopamine using nerve cells. Both of these techniques have helped us further understand the effects of these hormones.
It is important to note that the risk allele (a variant form of a gene that is located at the same location on a specific chromosome) is also required for consideration. Once the specific gene has been selected, we must look at which allele is the one responsible. This allele can be recessive genes and can pass symptoms of anxiety and depression across generations.
Depression being recessive
A British study suggests that a certain chromosome may have some impact on depression is recurrent. This chromosome is called 3p25–26 (also known as the depression gene) and is one of the most promising in that field. The studies of genes have been on the rise in recent years, however, we still have a very long way to go.
Why we feel anxiety and depression
Anyone who has suffered from mental health issues understands that it is not only emotional torment that you suffer from but physical pain. Often times it is simply muscle pain from constant worry, however, these symptoms can be crippling. Raises in blood pressure are extremely common, resulting in dizziness, confusion, sweat and panic attacks. The scariest part is that these feelings are often uncontrollable, these symptoms can present themselves any time, anywhere. The feeling of not being able to control our own feelings is crushing and often leads to symptoms of depression. It is difficult to learn to not only learn to deal with these feelings but to embrace them. We need to learn that there are so many others struggling with the very same things you do daily. Remember, you are not alone.
How does depression affect our brains?
Researchers also look at which parts of the brain anxiety and depression are present. The amygdala is a part of the emotional part of our brains (The amygdala is responsible for immediate emotional response) and is widely responsible for these symptoms. It is believed that when we feel symptoms of anxiety or depression, it is due to the fact that signals in our emotional brain overpower those in our cognitive brain. The emotional brain is overpowering the cognitive brain and these thoughts and feelings enter our consciousness.
Visual representation of depression
At age 16, Christian Hopkins was diagnosed with depression. He decided to take photos trying to capture what he has felt in his life, here are a few pictures from the collection:
Circadian clock and bipolar disorder
It is human nature to wake up and sleep with the sun. In recent years and with the drastic increase in screen usage and reduction in activity, people tend to rise and go to bed later than ever. This can be tied to depression and other forms of mental illness. When we look at major depressive disorder (MDD), it is clear that there is a pushback on our REM cycles as well as the time we wake up. The majority of studies surrounding mental illness and sleep patterns focus on bipolar (BPD) disorder. Often times people that suffer from BPD are also impacted by REM sleep latency, this can be tied to seasonal affective disorder as well as genetic polymorphism (When two or more alleles are found at a single locus at a frequency greater than 1%) in the CLOCK gene (the gene believed to be responsible for our circadian rhythms). Another big contributor is believed to be the GSK3 gene which is very common in BPD patients.
Anxiety and our circadian rhythm
Although many forms of mental illness are tied to our circadian rhythms, anxiety is not typically one of them. Instead, patients suffer from insomnia and nightmares. Anxiety is usually accompanied by other disorders such as depression, those other disorders usually have more of an impact on sleep. However, patients with anxiety can benefit from such alterations. Interesting tests have shown that altering circadian clock-related genes may have positive effects on anxiety. These mutations were performed on mice and led them to enjoy open spaces, which mice tend to avoid.
Given these early tests, we have learned that there is a strong correlation between BPD and the CLOCK gene. With this information, we can use CLOCK as a target region for future genetic modifications and studies.
Depression affect on our circadian rhythm
Sleep issues are prevalent in patients with depression and are often one of the first signs. Doctors have compared brain samples of post-mortem volunteers and found that the activity of genes in people suffering from depression at the time of death was not following a 24-hour cycle. The hypothalamus is largely responsible for setting the 24-hour pace in our bodies. Researchers took samples of genes from various major regions in our brains. For healthy samples, an average of 11 of the 16 genes showed the clearest cycle patterns cycled in four or more brain regions. In a variation, only two genes showed the same property of cycling, with non-reaching more than three regions in people suffering from depression. Another key point is that genes that should be shifting together were not. It is believed that these people were not sleeping at the correct time for their bodies, indicating that depression causes both shifting and disruption in circadian rhythm. Both patients use and not using antidepressants at the time of death and it is concluded that depression is responsible for these changes and not the medication. This suggests that rather than having a cycle, those with depression have a “flattened” rhythm.
The above diagram demonstrates the predicted time of death (Outer circle) and the actual time of death (Inner circle). We see that the predictions were much more accurate for “normal” people.
Conclusions
As we can see from various tests, studies and experiments, genes are tightly tied to sleep cycles and have extreme effects on our mental state. Mental health is a very difficult topic to speak about, however, it is necessary. There is science behind these problems and we need to do everything in our power to find the root causes. Through the use of gene editing and gene therapy, we can manipulate certain genes for example CLOCK in hopes of people suffering from severe mental trauma. We are not at this stage yet, but we are well on our way.
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