For example, while some studies have found no significant difference in the methylprednisolone response among childhood idiopathic thrombocytopenic purpura patients with the MDR1 3435 C>T variant, others have reported differing responses in patients with rheumatoid arthritis depending on their MDR1 genotypes [71]. The gene discussed is ABCB1; the disease is thrombocytopenic purpura.