NRAS And FMS Gene Mutation In Idiopathic Thrombocytopenic Purpura And Myelodysplasic Syndrome

Object Idiopathic thrombocytopenic purpura is an immune-mediated thrombocytopenic disease, which is the most common cause for abnormal bleeding. Myelodysplastic syndrome is an acquired clonal disease affecting both hemopoietic stem cell and progenitor cell , characterized by ineffective hematopoiesis and dyshaematopoiesis; They are distinctly different in pathogenesis, course of disease and prognosis. But both of them may first present as isolated thrombocytopenia, diagnosis established by exclusion ,the overlapping clinical appearance make the differential diagnosis difficult. This research discuss the NRAS, FMS gene mutation in aged idiopathic thrombocytopenic purpura patients and myelodysplastic syndrome patients to augment the understanding of the pathogenesis of ITP and improve the differential diagnostic criteria with myelodysplasia syndrome.Materials and Methods The research is a case-control study. We collected the bone marrow of 25 ITP patients , 8 MDS patients and 10 normal controls in Han nationality, and separated the mononuclear cells from the bone marrow which include substantial immature cells ,then extracted their genomic DNA. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was performed to detect the point mutation frequency of 12> 13 codon in N-ras gene and 301,969 codon in FMS gene in aged ITP patients, which occurred more frequently in MDS patients.Results No mutation was found in normal controls . In 25 ITP patients, One mutation of NRAS gene was detected, One mutation of FMS gene is found in another patient. Three mutations were positive in MDS patients. Among them two has NRAS gene mutation(25%),one has FMS gene mutation(12.5%).Conclusions ITP and MDS may be overlapping in clinical manifestations and pathogenesis, and the patients with NRAS and FMS gene mutation should be ruled out from ITP and classified into MDS again.