[5Q minus syndrome. A rare disorder caused by loss of part of the long arm (Q arm) of human chromosome 5. This syndrome affects myeloid (bone marrow) cells, causing treatment-resistant anemia, and myelodysplastic syndromes that may lead to acute myelogenous leukemia. ( NCI )] (UMLS (NCI) C0740302) Myelodysplastic Syndrome Associated with Isolated del (5q) Chromosome Abnormality =Disease or Syndrome ;