Depression is a quite widespread disease of nowadays. Scientific sources and mass media already have some success in conveying to society the thought that depression is something more than negative mood that can changed by itself. It is the disease, and like any other disease, it requires treatment. Even though depression can't be successfully cured, it is always the better way to prevent the disease. However, preventing depression requires at first answer the question about the causes of this disease. There are different views about this issue. Some researchers claim that the main cause of depression is genetic. Other claims that environment is more important in the context of depression. However, as it often happens, and as the studies confirmed, the both sides have correct suggestions and the both causes, genetic and environmental, are important for the development of depression.
As it was already mentioned above, there are some researchers who claim that genetic factor is the main cause of depression. For example, the study that genetic factors play important roles in the development of major depressive disorder (MDD), “as indicated by family, twin, and adoption studies, and may reveal important information about disease mechanisms”. As one can see, there are some studies that confirm the importance of genetic factor for the development of depression. However, not only the studies about the family, twin, and adoption show such results. England & Sim, (2009) refer to the studies of Sullivan, Neale, and Kendler, claiming that “about one-third of the risk for major depression in adults derives from genetic differences between individuals.” Moreover, the researchers even point to the specific genes that are related to the development of depression. Thus, England & Sim noticed that there are “several genetic polymorphisms have been linked to increased risk of depression in response to stress. Foremost among these are genes of the serotonin system (5-HT).” The fact that there are specific genes that take part in causing depression make the thesis about genetic as the key factor that causes depression especially strong. In any case, it must be clear that for depression, as for any other mental disease, genetic factor has quite an important role. Thus, Hyman wrote that “family, twin, and adoption studies have shown that, for schizophrenia, autism, manic depressive illness, major depression, attention deficit hyperactivity disorder, panic disorder and other mental illnesses, the transmission of risk is due to heredity”. In this way, there is a list of many mental disorders caused by genetic factors, and it is logical that depression can be among them. Besides, as it was mentioned above, the studies found specific genes that are related to the development of depression.
However, there is one more view on this issue. As far as depression is mental health, it is related not only to the physical state of human body, including all complex process and part of it but also with the human psyche. It is known the fact that human psyche and state of the body are related. Depending on the human emotions, the body produces different types of hormones which can affect the state of the body in one or another way and causes a person’s mood. Taking this into account one can consider an environmental factor as that which causes depression, comparing it with effect on low temperature on a human body. It is known fact that if a human is under the influence of low temperature long enough, he or she can get sick. However, it is also known that the low temperature by itself is not the reason for disease. Impact of low-temperature affects the human body, in particular, reduces the immunity, and that is why risks to get sick increases after the cases of freezing. The environmental factors can have the similar relationship with the depression. Even though the negative environmental factors can not be the main reason for depression they can have a generally negative effect on the mental state of the human, thus, they become the key factor that causes depression because without their impact it could not develop. There are some studies that confirm that the environmental factors cause depression. “Onset of mood disorders such as depression is undoubtedly impacted by stressful life events that occur in childhood” . The authors considered the study in which the researchers paid attention to the experience of approximately two thousands women of various socioeconomic levels, and came to the conclusion that “those with a history of childhood physical or sexual abuse had an increased risk of depression and anxiety” . The study also showed that women with a history of childhood abuse “have a four-fold increased risk of developing depression” and “early life trauma has also been shown to impact the clinical course of depression” . Generalizing the conclusion of the study, the researchers identified four main points about patients with depression who have a history of childhood trauma. The researchers wrote that such patients have “(a) lower rates of remission and recovery, (b) longer episodes of depression, (c) a more chronic disease course and (d) earlier onset of depressive symptoms” These results clearly show that the life experience and environmental factors are significant as causes of depression.