Treatment for HPS-related IBD resembles those for Crohn’s disease and ulcerative colitis, but responses to therapy are variable in patients with HPS, many of whom presented poor clinical response to corticosteroids and had to be treated with anti-TNF alpha biologic drugs (Felipez et al., 2010; Hazzan et al., 2006; Kouklakis et al., 2007). The gene discussed is TNF; the disease is Hermansky-Pudlak syndrome.