Background: FACL6 is involved in activation of long-chain fatty acids for both synthesis of cellular lipids, and degradation via beta-oxidation. It plays an important role in fatty acid metabolism in brain and the acyl-CoAs produced may be utilized exclusively for the synthesis of the brain lipid. FACL6 is expressed predominantly in erythrocyte precursors, in particular in reticulocytes, fetal blood cells derieved from fetal liver, haemopoietic stem cells from cord blood, bone marrow, and brain. Expression is low at earlier stages of erythroid development but is very high in reticulocytes. This protein is involved in myelodysplastic syndrome (MDS) with basophilia, acute myelogenous leukemia (AML) with eosinophilia, and acute eosinophilic leukemia (AEL). It is characterized by a chromosomal translocation t(5,12)(q31,p13) that involves ETV6 and ACSL6.