No differences were detected between males and females of En2+/+, +/− and −/− mice for juvenile reciprocal social interactions, adult social approach, fear conditioning, Morris water maze, forced swim, tail suspension, acoustic startle, prepulse inhibition, pup ultrasonic vocalizations, anxiety-like behaviors, open field locomotor activity, rotarod performance, olfactory habituation/dishabituation, self-grooming, pup developmental milestones and the majority of general health parameters. This evidence concerns the gene EN2 and Anxiety.