Here we investigate if the PRKACA mutations leading to hyperactivity of PKA signalling in CPA are associated with the loss of RIIβ protein levels and demonstrate a clear connection between RIIβ protein levels and the mutation status of PRKACA. Furthermore, we describe a comprehensive pattern of PKA subunits expression in the different zones of the adrenal cortex and speculate about the functional consequences of these findings. This evidence concerns the gene PRKACA and congenital primary aphakia.