 This study found that there is a strong genetic correlation between depression and breast cancer, as well as a possible causal relationship between the two conditions. The researchers also identified several specific genomic regions that are linked to both conditions, as well as five shared genes. Additionally, they used a method called bidirectional Mendelian randomization to show that depression causes an increase in the risk of developing breast cancer, while breast cancer does not cause an increase in the risk of developing depression. This suggests that there is a shared genetic basis between the two conditions, which could lead to further research into how to reduce the risk of breast cancer. This article was offered by Shuiyou Wu, Wenqiang Zhang, Zanying Zhao, and others.