The human brain is a very complex system, just like a city, it strives for order and efficiency. However, a patient with bipolar disorder has a very chaotic type of brain function; which causes mood changes and sometimes suicidal thoughts. Bipolar disorder is a common psychiatric mood disorder defined by recurrent episodes of abnormally elevated mood and depression, changes in energy and ability to carry out daily activities. (Joel, Jakosson and college) “Bipolar disorder (BD) is a chronic illness with a high risk of recurrence. This disease also leads to a high mortality rate by suicide." (Sabrina, Paterniti and Jean-Claude Bisserbe) Many studies show that this disorder is genetic and therefore runs in families, passing from generation to generation. The more related you are to a person with bipolar disorder, the more likely you are to have bipolar disorder. There are two types of bipolar disorder: bipolar I and bipolar II. “Bipolar I disorder is defined as present if the person experiences one or more episodes of mania and usually episodes of depression during his or her lifetime. The severity and duration of the episodes are often severe and may result in hospitalisation." (Black Dog Institute) “Bipolar II disorder is defined as present if the person experiences episodes of both hypomania and depression but no manic episodes. The severity of the highs does not lead to hospitalization." (Black Dog Institute) Bipolar disorder can cause depression, loss of sleep and/or appetite in patients. It could also make them feel worthless, guilty and hopeless, which could even lead to suicide if not treated properly. “Over 121 million people worldwide are affected by bipolar disorder. By 2020, depression is predicted to reach second place in the g...... middle of paper...... the purpose of this study was to investigate the potential role of monocyte chemoattractant gene polymorphism protein 1 in conferring susceptibility to mood disorders”. (Carlo, Altamura and colleagues) The results of their study suggest not only a clinical but also a genetic and biological difference between the subtypes of mood disorders. (Carlo, Altamura and colleges) There are many other studies being carried out all over the world; those were just some of the ones that were done. Every study that has been or will be done helps reach answers as to why and what causes bipolar disorder. There the lives of millions of people can be improved and treatment options will continue to grow dramatically. Every day a person is diagnosed with bipolar disorder, and every day we are closer to the answers on how to better cure and treat this great burden on a person's life.