Transcriptome analysis of Chd8 S62X heterozygote mutant and wild-type mice

Autism spectrum disorders (ASD) are ~4-times more common in males than females, and CHD8 (a chromatin remodeler)-related ASD shows a strong male bias (~5:1), although the underlying mechanism remains unclear. Chd8-mutant mice with a C-terminal protein-truncating mutation (N2373X) display male-preponderant behavioral deficits as juveniles and adults, although whether this also applies to other Chd8 mutations remains unknown. Here we report that new Chd8-mutant mice with a stronger N-terminal protein-truncating mutation (S62X) display male-preponderant autistic-like behaviors at juvenile stages, but as adults, both males and females share behavioral deficits. Excitatory synaptic transmission is suppressed and enhanced in male and female juvenile Chd8+/S62X mice, respectively, but similarly enhanced in adults. ASD-like transcriptomic changes occur monophasically in newborn and juvenile (but not adult) males but biphasically in newborn and adult (not juvenile) females. Therefore, a strong CHD8 mutation induces early-onset ASD-like phenotypes in males but late-onset phenotypes in females after juvenile-stage female protection. Whole brain transcriptome analysis of Chd8 S62X heterozygote mutant and wild-type mice