Mental illness like all other diseases, is contributed to by genetic factors. Whether they encode for having the mental illness, by constructing an abnormal brain chemistry, or make one more susceptible to having a mental illness. note: Mental illness is also very much contributed to by environmental factors. Because there is a genetic link to mental illness, the specific genes that contribute to mental illness can be found.
Researchers from QIRM Berghofer have mapped out the genes that contribute to depression and anxiety, using genetic data from over 400 thousand individuals. 674 genes were identified and 509 of those genes were relevant in both illnesses (roughly 75%). The researchers also discovered when analyzing the genes only linked to anxiety, there was a strong overlap with genes linked to hypertension. Genes only linked to depression had a strong overlap with genes linked to hypertriglyceridemia, which suggests depression may also have metabolic components. I think the more we learn about the genetic linkages to mental illness the easier it will be to treat and or medicate for individuals. I think pretty soon, when someone has depression or anxiety we can analyze their genome find the exact receptor problem their genes have coded and create a individual specific inhibitor (or reuptake inhibitor) to treat them.