The clinical impact of such signal dysregulation can be appreciated in disorders, which involve mutations in this metabolic pathway: patients with mevalonate kinase deficiency develop severe and recurring autoinflammatory fevers, associated with dysregulated B-cell responses including elevated serum immunoglobulin levels.78 Patients with mevalonate kinase deficiency demonstrated reduced frequency of CD24hiCD38hi B cells and poor IL-10 responses across all B-cell subsets when compared with healthy individuals. The gene discussed is IL10; the disease is hyperinsulinemic hypoglycemia, familial, 4.