Figure 4.

CHRNA7 transcript levels decline significantly with age in the human cortex. QRT–PCR analyses of CHRNA7 expression in normally developing control (CTRL, N = 20), Rett (RTT, N = 7) and autism (AUT, N = 12) were performed on RNAs isolated from frozen, post-mortem Brodmann area 9 cortices using CHRNA7- and GAPDH-specific primers. Fold change of CHRNA7 expression relative to GAPDH was calculated using the comparative Ct method for each sample. CHRNA7 expression declines rapidly from 4.0-fold relative to GAPDH in 4-month-old cortex to ∼0.4-fold in 57-year-old cortex. Analysis of CHRNA7 expression levels was done using a one-way ANCOVA with age as a covariate showing that age has a significant relationship to CHRNA7 expression (P< 0.0001).