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bioRxiv · 10.1101/2020.02.05.936260

Effects of a postnatal Atrx conditional knockout in neurons on autism-like behaviours in male and female mice

Abstract

BackgroundAlpha-thalassemia/mental retardation, X-linked, or ATRX, is an autism susceptibility gene that encodes a chromatin remodeler. Mutations of ATRX result in the ATR-X intellectual disability syndrome and have been identified in autism spectrum disorder (ASD) patients. The mechanisms by which ATRX mutations lead to autism and autistic-like behaviours are not yet known. To address this question, we generated mice with postnatal Atrx inactivation in excitatory neurons of the forebrain and performed a battery of behavioural assays that assess autistic-like behaviours. MethodsMale and female mice with a postnatal conditional knockout of Atrx were tested in a battery of behavioural tests that assess autistic features. We utilized paradigms that measure social behaviour, repetitive and stereotyped behaviours, as well as sensory gating. Statistics were calculated by two-way repeated measures ANOVA with Sidaks multiple comparison test or unpaired Students T-tests as indicated. ResultsThe behaviour tests revealed no significant differences between Atrx-cKO and control mice. We identified sexually dimorphic changes in odor habituation and discrimination; however, these changes did not correlate with social deficits. We additionally observed sex-specific differences in sociability, vertical episodes, and acoustic startle response when results were analyzed by sex. ConclusionThe postnatal knockout of Atrx in forebrain excitatory neurons does not lead to autism-related behaviours in male or female mice.

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BibTeXRIS

Martin-Kenny, N. A., Berube, N. G.. 2020-02-07. Effects of a postnatal Atrx conditional knockout in neurons on autism-like behaviours in male and female mice. https://doi.org/10.1101/2020.02.05.936260

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