To address directly this question and obtain a possible mouse model for PPNAD, we produced mice with targeted Prkar1a gene inactivation in adreno-cortical cells by mating Prkar1a floxed mice with Akr1b7-Cre mouse line, a Cre expressing line allowing specific gene ablation in the steroidogenic lineage of the adrenals [13]. This evidence concerns the gene PRKAR1A and primary pigmented nodular adrenocortical disease.