The occurrence of a kidney disease phenotype in B6.Podocin/cre,Pdss2loxP/loxP but not B6.PEPCK/cre,Pdss2loxP/loxP mice resolves a long-standing question regarding the cellular localization of the primary defect in B6.Pdss2kd/kd mice [3],[20]. The gene discussed is PCK2; the disease is kidney disorder.