t(3;21)(q26;q22)

**Semantic type:** Cell or Molecular Dysfunction

**Definition:** A cytogenetic abnormality that refers to the translocation of the long arm (q26) of chromosome 3 and the long arm (q22) of chromosome 21. It is associated with RUNX1/MECOM fusions, chronic myelogenous leukemia in blast crisis (BC-CML), myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML).

**Synonyms:** - t(3;21)(q26.2;q22) - t(3;21)(q26.2;q22)