Genes and Mental Illnesses: Is There a Connection?

https://www.sydney.edu.au/news-opinion/news/2024/04/29/do-our-genes-play-a-role-in-depression--.html

Psychologists have been studying the brain and the cause of mental illnesses for at least 150 years. Many have claimed that the outside environment along with trauma have been the main cause of a mental illness. It was a relatively recent connection to study it with genetics/the gene. There are some who have worked with geneticists to point out, that there may be more than one connection between the brain, the mental illness and the gene. Genes tend to copy specific information from parents and pass it to their children. Coding a string of proteins that call for the makeup of a mental illness may not be any different than them coding it for hair color. There have been studies that show the coding sequences for certain mental illnesses such as depression may have overlapping codes for ADHD and schizophrenia as well. So removing a person from a harmful environment may not be the end all factor, if a certain mental illness was already programmed into a hard drive. 

This specific study is showcasing the reactive depression vs the endogenous depression. Meaning- are there people who have it developed due to environment or are people just born with it. Will those born with it built in have less of a stressful environment or more of a stressful environment, may have been one of the main questions that the study was trying to find out. A study across 14,000 people have showed that those with the genetic makeup of a mental illness has reported MORE of a chance of stressful factors. 

However, it is more complex than that because the study later showed that there was a combination of all factors involved (biological, environmental, and genetic) and that they were not independent of another. Other studies have not only tested genes vs depression but have extended the study to depression, genes and twins. Will those who share similar DNA be more prone to the same mental illnesses? The study tested fraternal twins vs identical twins to see if there was more or less of a link together. A main showcase of the study was pointing out that although the twins shared a lot of similar DNA how they processed the outside environment was different, thus furthering the endogenous vs reactive argument. 

https://www.sciencedirect.com/science/article/pii/S0022395624004278

edit: due to a miscommunication in registering I just copied and pasted my own work from a different account. Not plagiarizing or stealing someone else's work.