NINJ2 and major depressive disorder: Single nucleotide polymorphisms studies points out that mutations of Ninj2 could be risk factors of ischemic stroke and multiple sclerosis,[11] and even associated with suicide attempts.[12] Recent studies indicate that the expression of Ninj2 is downregulated in mice with stress‐induced depression.[13] However, whether and how Ninj2 plays a role in the development of depression is largely unknown.