PKHD1 and autosomal dominant polycystic kidney disease: One essential observation is the careful selection and validation of appropriate reference genes as a basis for normalizing the variability between samples in the corresponding study designs to each animal model used in the literature for experimental ADPKD research, amongst them Ksp/cre mice, Pkhd1/cre mice, Kif3aflox/flox mice, Pkd2flox/flox mice, Pkhd1−/− mice, Hnf-1βflox/flox mice, miR-17∼92flox/flox.