A subset of myelodysplastic syndromes (MDS) presents with ring sideroblasts (RS) mostly associated with SF3B1 (splicing factor 3B, subunit 1) mutation and are recognized as a subgroup of MDS by the 2022 World Health Organization (WHO) classification (called MDS with low blasts and mutated SF3B1 or MDS with RS) and the International Consensus Classification of Myeloid Neoplasms and Acute Leukemias (ICC) of 2022 (called MDS with mutated SF3B1) (1–3). The gene discussed is SF3B1; the disease is neoplasm.