In adulthood, ERα has been predominantly linked to reproductive neuroendocrine and sexual behaviors [1,2], whereas ERβ has been associated with many non-reproductive neurophysiological functions such as learning and memory [3,4], anxiety-related behaviors [5,6], and the stress response of the hypothalamic-pituitary-adrenal (HPA) axis [7]. This evidence concerns the gene ESR2 and Anxiety.