We first examined genes thought to have a role in the formation of ring sideroblasts in human SF3B1-mutant MDS, namely TMEM14C25 and ABCB7,28, 29 for which aberrant 3′ splicing was observed in humans, but not in Sf3b1K700E/+ mice. This evidence concerns the gene SF3B1 and myelodysplastic syndrome.