This is a pilot, open-labelled, to determine if oral administration of a single dose of ergocalciferol lowers plasma mucin-1 levels. The study population will include 40 healthy individuals and 40 individuals with ADTKD-MUC1.~The study consists of an initial screening, signing of consent of interested individuals, performance of pregnancy test in women of child-bearing age and screening labs, and administration of 200,000 units of ergocalciferol on Day 0 (On Study). Laboratory studies will be performed at baseline, on Days 3, 7, and 10.
To determine if a one-time oral administration of ergocalciferol results in a decline in plasma mucin-1 levels in healthy individuals and individuals with ADTKD-MUC1.