81. 已知基因突變發生在 polycystin 1 及 polycystin 2的是:(A)兒童多囊腎(childhood polycystic kidney)(B)成人多囊腎(adult polycystic kidney)(C)後天性囊病(acquired cystic disease)(D)尿毒性髓質囊病 (uremic medullary cystic disease)