PKD1 and polycystic kidney disease: Compound heterozygous PKD1 variants (p.Cys259Tyr and p.Ala1458fs) were identified and abdominal CT showed liver cysts and bilateral polycystic kidney disease at the age of 33, while only a total of 4 cysts (2 on each kidney) in the father (I-1, age 71) and no kidney cyst (image not shown, age 40) was detected in the sister II-2 (Fig. 5e).