In addition, cumulative evidences indicate importance of splicing factor gene mutations, which are most frequent mutations in MDS patients, in molecular pathogenesis of MDS.17, 18 Mutations of splicing factor genes may affect global gene expression and splicing, resulting in alteration of expression level and/or splicing in diverse genes, which may include the PLCG1 gene, involved in molecular pathogenesis of MDS. The gene discussed is PLCG1; the disease is myelodysplastic syndrome.