Genetic variants in CYP24A1 lead to a range of phenotypical and biochemical presentations, including idiopathic infantile hypercalcemia, elevated concentrations of 1,25 dihydroxy vitamin D, adult onset nephrocalcinosis, hypercalciuria, hypercalcemia and nephrolithiasis. The gene discussed is CYP24A1; the disease is hypercalcemia disease.