Tetratricopeptide repeat domain 9A knockout induces social anxiety and impairs offense behaviors in female mice

Objective(s): The involvement of tetratricopeptide repeat domain 9A (TTC9A) in anxiety-like behaviors through estrogen action has been reported in female mice, this study further investigated its effects on social anxiety and aggressive behaviors. Materials and sMethods: Using female Ttc9a knockout (Ttc9a-/-) mice, the role of TTC9A in anxiety was investigated in non-social and social environments through home-cage emergence and social interaction tests, respectively, whereas aggressive behaviors were examined under the female intruder test. Results: We observed significant social behavioral deficits with pronounced social and non-social anxiogenic phenotypes in female Ttc9a-/- mice. When tested for aggressive-like behaviors, we found a reduction in offense in Ttc9a-/- animals, suggesting that TTC9A deficiency impairs the offense responses in female mice. Conclusion: Future study investigating mechanisms underlying the social anxiety-like behavioral changes in Ttc9a-/- mice may promote the understanding of social and anxiety disorders.