 It was named this because some people with the disease had cysts (small holes) in the middle (medulla) of their kidneys.It has since then been found that these cysts are uncommon and are not found in the majority of the patients with MUC1 mutations.For this reason, this name has been abandoned, scientists (part of the Kidney Dialysis Initiatives and Global Outcomes group) specializing in this disease came together formally and created an official name for this and similar conditions.