Boertin et al. (46) reported a significant association of copeptin levels with ADPKD severity in a prospective study of 79 ADPKD patients (baseline GFR 96.8 ± 18.2 ml/min/1.73 m2) followed-up for 11 years. The gene discussed is AVP; the disease is autosomal dominant polycystic kidney disease.