Genetic Predisposition to Schizophrenia May Increase Risk to Psychosis from Cannabis use

 

    

    According to Translational Psychiatry, researched showed that people with genetic predisposition to schizophrenia had higher rates of psychotic experiences compared to general cannabis users. The researched showed that “the true influence of genetics on the cannabis-psychosis relationship may be even greater than what we found here.” The study was done on general cannabis user and participants with the highest genetic risk scores for schizophrenia. For people who used cannabis before, about fifty percent reported psychotic experiences. For the participants who had the highest genetic risk scores for schizophrenia, sixty percent of them showed psychotic experiences. Overall, researchers are still trying to gain a deeper understanding about the connection between cannabis and psychosis. The findings of this research will help make more informed decisions about drug use.

Articles:

https://neurosciencenews.com/cannabis-psychosis-schizophrenia-18235/

https://www.nature.com/articles/s41398-021-01330-w

Four Different Genes Associated With Schizophrenia

Schizophrenia is a brain disorder that alters someone's perception of reality and causes abnormal social behavior, with symptoms beginning around age 20. There is currently no cure, and as negative social connotations associated with the disease continue to grow, a scientific obligation to understand schizophrenia on a deeper, genetic level arises. In January of this year, multiple scientists from NYU and other institutions did just that - after analyzing 48 separate case studies of people with schizophrenia, it was discovered that four separate signaling genes are involved with the disease. Combinations of these four genes lead to differing phenotypic expressions that may explain why the symptoms of schizophrenia are so widely varied. A quick Google search pulls up a slew of symptoms - from behavioral (social isolation, lack of restraint, aggression), to cognitive (delusion, amnesia), to psychological (hallucination, paranoia), and beyond. It's not surprising that Kranz et al.'s study revealed at least four different genes involved with this disease that affect a person's phenotype, classifying schizophrenia as a polygenic disorder. They also discovered that these genes impact the growth or regulation of nerve circuits within the brain.

In order to conduct this study, scientists studied 48 ethnically diverse individuals all affected with the disease. They had them undergo targeted exome sequencing of the four genes in question: PTPRG (Protein Tyrosine Phosphatase, Receptor Type G), SLC39A13 (Solute Carrier Family 39 (Zinc Transporter) Member 13), TGM5 (transglutaminase 5), and ARMS/KIDINS220 (Ankyrin repeat-rich membrane spanning protein or Kinase D-Interacting Substrate of 220 kDa). 15 out of the 48 cases (a little over 30%) were all shown to have "rare or novel missense coding variants" (Kranz et al. 2016) in one or more of these genes.

The first gene, PTPRG, was shown to influence traits such as working memory deficits and connection of nerve cells as they form nerve networks. The second gene, SLC39A13, was shown to be associated with severe negative symptoms, global cognitive deficits and poor educational attainment (suggesting a developmental disorder). This can lead to low achievement at school and decreased levels of motivation. The third gene, TGM5, is associated with slow processing speed, childhood attention deficit disorder and other milder symptoms of schizophrenia. Also, this gene is associated with stabilization of proteins that can lead to degenerative conditions that are found in Huntington's disease. The fourth gene, ARMS/KIDINS220, plays a role in global cognitive deficits with good educational attainment, suggesting neurodegeneration after a certain age, usually a little later in life (around 22).

This experiment is extremely important for psychologists, psychiatrists, neurologists, those affected with schizophrenia, and those who may be at risk. Instead of using 'schizophrenia' as a blanket term for everyone exhibiting multiple and varied symptoms of psychosis, this study directly implies that person-specific treatments are needed. If two people both have schizophrenia, their phenotypic expressions may be greatly varied, but may receive the same treatment - which may help one and not the other, or help neither at all. In the future, it's possible schizophrenia may be broken down into multiple classifications of different disorders, which makes more sense in terms of treatments. I hope this experiment leads to more studies, shedding better light on this disorder, reducing the stigma surrounding it, and ultimately leading to some type of cure.





Original Article: http://www.medicalnewstoday.com/articles/309631.php

Psychosis from marajuana may be due to a genetic variation

Scientists from King's College London's Institute of Psychiatry have found that there is a strong influence of the genetic variant, AKT1 on psychosis induced by the use of marajuana. A study was conducted in which researchers genotyped and  investigated the AKT1 gene in 700 participants. AKT1 codes for a protein, RAC-alpha serine/threonine-protein kinase and also signals dopamine. Dopamine levels are abnormal in marajuana users experiencing psychosis. From their study, these researchers were able to conclude that the AKT1 genotype highly influences psychosis in marajuana users.

What led them to this conclusion was that they discovered that people who frequently used marjuana and possessed this gene variant, were twice as likely to develop mental impairment usually associated with the intake of pot. Their chances heavily increased, as much as seven times as much, if they were frequent and daily users. With this new information, it will not be long before treatments are created that reverse this process of psychosis after the intake of this drug.

Artistic tendencies linked to ‘schizophrenia gene’

A genetic mutation that is linked to psychosis and schizophrenia is also shown to influence creativity. This may be one of the reasons why mutations that increase the chances of a person having a mental illness have not been filtered out of our genes. The gene neuregulin 1 has been linked to mental illness and a single DNA letter mutation of this gene has been linked to psychosis, poor memory, and sensitivity to criticism.



Salvador Dali's mental disorders were also the key to his creativity.

This study genotyped 200 adults who were considered and scored to be creative. People who had two copies of the neuregulin 1 mutation had higher scores on their creativity than did those who had either one or no copies of the neuregulin 1 mutation. How this affects creativity has yet to be determined however, the likelihood of having schizotypal traits with two copies of the mutation was no more likely than the other participants. It is suggested that this mutation could dampen the prefrontal cortex that helps to control mood and behavior. It could make come people very creative and make others psychotic. Intelligence could help to determine which of these occurs, with smarter people having a tendency to be more creative and less smart people having more psychotic issues. Those with high intelligence and psychosis tend to have a better time dealing with their psychosis and expressing it.

I find this information to be very interesting as it is a kind of typical assumption in society sometimes that insanity and creativity may be linked. Now there seems to be a genetic factor causing this. It would be interesting to see what other traits could be linked to genetics.

 

Link Between Schizophrenia and Bipolar Disorder Found

A recent study into the genetic imperatives of schizophrenia has found a total of seven locations on the genome that have been linked to the disease. A previous study into Bipolar disorder revealed a finding of four genes linked to the ailment. Interestingly enough, three of these genes crossover and are some of the same ones found on schizophrenia, thereby confirming the link between the two disorders. Researchers previously had already suggested that the two disorders were linked, but never had any definitive proof. Due to the complexity of the diseases, it was difficult to dissociate the different genes complexes and environmental factors involved. These studies have allowed scientists to identify a whole host of genetic risk factors associated with the two disorders. Furthermore, by knowing exactly which genes trigger which psychosis, researchers can now develop more effective drugs to target those specific areas.

http://medicalxpress.com/news/2011-11-powerful-genetic-psychosis-date.html (Article Link)