Downregulation of [GABA.sub.A] receptor protein subunits α6, β2, δ, ζ, γ2, θ, and ρ2 in superior frontal cortex of subjects with autism

We measured protein and mRNA levels for nine gamma-aminobutyric acid A ([GABA.sub.A]) receptor subunits in three brain regions (cerebellum, superior frontal cortex, and parietal cortex) in subjects with autism versus matched controls. We observed changes in mRNA for a number of [GABA.sub.A] and [GABA.sub.B] subunits and overall reduced protein expression for [GABA.sub.A] receptor alpha 6 (GABRα6), [GABA.sub.A] receptor beta 2 (GABRβ2), [GABA.sub.A] receptor delta (GABRδ), [GABA.sub.A] receptor epsilon (GABRζ), [GABA.sub.A] receptor gamma 2 (GABRγ2), [GABA.sub.A] receptor theta (GABRθ), and [GABA.sub.A] receptor rho 2 (GABRρ2) in superior frontal cortex from subjects with autism. Our data demonstrate systematic changes in [GABA.sub.A&B] subunit expression in brains of subjects with autism, which may help explain the presence of cognitive abnormalities in subjects with autism.