Gene expression profiling in myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are a heterogenous group of hematopoietic stem cell disorders characterized by dysplastic blood cell formation and peripheral blood cytopenias. Up to 30% of patients with MDS will progress to a highly chemotherapy-resistant secondary acute myeloid leukemia (sAML). We identified mutations in U2AF1 in MDS patients and patients with U2AF1 mutations are at an increased risk of developing sAML. We identified mutations in U2AF1 in patients with MDS and hypothesized that U2AF1 mutations may represent a novel mechanism that could alter gene expression in MDS. To elucidate gene expression changes associated with U2AF1 mutations, we analyzed the global mRNA expression profile obtained from bone marrow CD34+ cells purified from 6 MDS patients with a U2AF1 mutation, 9 MDS patients without a mutation, and 4 normal donors.