Overall, particularly after early life conditions that lower the level of maternal care, SERT+/− mice and rats can be more sensitive compared to SERT+/+ mice and rats, to develop anxiety- and depressive-like behavior or increased stress coping (Carola et al., 2008; van den Hove et al., 2011; van der Doelen et al., 2013), whereas in other studies using different stressors no such interaction effects were found (e.g., Kloke et al., 2013; Bodden et al., 2015). Here, SLC6A4 is linked to Anxiety.