A Novel Approach using CRISPR-Cas9 and Long-Reads to Analyze Biallelic PKD1 Inactivation in Human Cystic Epithelial Cells for ADPKD

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is the leading cause of genetic kidney failure, accounting for 6-10% of all dialysis patients in the United States. This monogenic disease is characterized by the formation of fluid-filled cysts in the kidneys and enlargement resulting in renal failure, with the only treatment options being dialysis or transplant. A mutation in one allele of the polycystin-1 (PKD1) gene accounts for 85% of ADPKD cases. While germline mutations typically result in uniform phenotype expression, a sporadic and non-uniform cyst formation is seen in ADPKD.

Likewise, in inherited cancers, tumors only develop in cells where a second somatic mutation occurs in addition to the germline mutation in all cells. Both cysts and tumors are also clonal, arising from a single mutated cell resulting in abnormal growth. These similarities suggest that Knudson’s “two-hit” hypothesis, which was found to be true for numerous cancers involving tumor suppressor genes, may be applicable to ADPKD.