Also, in case of a non PKD1 non PKD2 family, in which there is a clear ADPKD family history, but the PKD gene mutational analysis remains negative, exclusion of the disease in at-risk individuals will be possible only by means of a negative renal US at the age of 30–40 years or older (70). This evidence concerns the gene PKD1 and autosomal dominant polycystic kidney disease.