MUC1 and autosomal dominant medullary cystic kidney disease with or without hyperuricemia: Among the 93 families with ADTKD-MUC1 in Olinger et al.4 study, 87 presented with a cytosine duplication (27dupC, 93.5%), 3 with an adenine duplication (28dupA, 3.2%), 2 with a guanine insertion (26_27insG, 2.2%), and 1 with a small indel (23delinsAT, 1.1%).