Myelodysplastic Disease Associated with Deletions of Chromosome 5q Region

The only cytogenetic alteration defining a subtype of a myelodysplastic syndrome is represented by the deletion of the long arm of chromosome 5 (del(5q)), now classified as MDS with isolated del(5q). This subtype is associated with a peculiar phenotype mainly dependent by the haploinsufficiency of several genes located on the deleted arm of chromosome 5. These patients show a good prognosis and respond to treatment with lenalidomide, but some cases progress to acute myeloid leukemia. Molecular studies have in part elucidated th heterogeneity of MDS with isolated del(5q) mainly related to the association with different co-mutations that may affect leukemic transformation and survival.