Various IDELS of SLC29A3 have been linked to diseases including Faisalabad histiocytosis (FHC), H syndrome, sinus histiocytosis with massive lymphadenopathy (also known as familial Rosai-Dorfman disease), pigmented hypertrichosis and insulin-dependent diabetes have all been proposed to form part of a continuous ’SLC29A3 spectrum disorder’ (Morgan et al., 2010). The gene discussed is SLC29A3; the disease is H syndrome.