Several SAM-domain proteins that bind each other are mutated in patients with cystic kidneys or laterality defects, including the Ankyrin (ANK) and SAM domain-containing proteins ANKS6 and ANKS3, and the RNA-binding protein Bicc1.
These variants are unlikely to account for PKD in these patients, yet the screening of other affected populations may provide information about the involvement of PKDR1 as a modifier gene in cystic kidney disease.