GABRB2 and in situ carcinoma: In the PFC, GABRB2 also exhibited a similar expression pattern as GABRA1. Analysis of the change in the mRNA level of GABRB2 revealed a significant effect of age [F(1, 32) = 14.324, P < 0.05], CIS exposure [F(1, 32) = 10.751, P < 0.05] and their interaction [F(1, 32) = 16.493, P < 0.05].