Further, PLD2 is not only involved in neurotransmission and neurodevelopment, but also affected in neurological disease (Gratacòs et al., 2009; Ghim et al., 2016), while ATF5 is an important regulator of cerebral cortex formation, which functions in cerebral cortical neuroprogenitor cells to maintain their proliferation and block their differentiation into neurons; ATF5 is also associated with bipolar disorder (Kakiuchi et al., 2007). Here, ATF5 is linked to bipolar disorder.