PKD1 and cystic kidney disease: In the current study, we generated heterozygous PKD1 KO cloned pigs harboring the unique mutation c.152_153insG (PKD1insG) in the first exon of PKD1. The resulting PKD1insG/+ cloned pigs displayed characteristics of an ADPKD model, including (i) neonatal renal cyst formation, (ii) progressive cyst development during animal growth, and (iii) sustained fertility after sexual maturation.