,15 Notably, about 10% of patients with atypical or “class 2” cyst distributions, described as unilateral, segmental, asymmetric, lopsided, or with atrophy, were excluded from the Mayo Clinic classification, but have a mild prognosis and are less likely to have a pathogenic PKD1 or PKD2 variant.16 Here, PKD2 is linked to cyst.