Abstract:

Depression has highly complicated polygenic underpinnings that do not follow the law of Mendelian inheritance. However, existing research on the genetic mechanism of depression has primarily focused on the effects of single candidate genes. Recent studies using the method of polygenic risk scores and the gene by gene interactions approach have provided new evidence respectively for the existence of both additive genetic effects and interactive genetic effects on depression. These studies demonstrated that multi- genes interact with environmental factors in their effects on the etiology of depression, and gender has a strong influence on these interactions. It is assumed that the effects of multi-genes on depression would be possibly mediated by the specific endophenotypes, such as cognitive factors, personality and stress hormone. Future research in this realm should pay greater attention to the interactions between multi-genes and multi-environments, gender differences in the polygenic underpinnings and the dynamic changes in polygenic effects over development.

Key words: depression, polygenic, endophenotypes, gender difference