CEL can be an isolated ocular disease known as ectopia lentis syndrome (ELS) or be secondary to systematic disorders, such as Marfan syndrome (MFS), and both pathologies can be caused by fibrillin-1 (FBN1) mutations (Faivre et al., 2008). This evidence concerns the gene FBN1 and Chronic Eosinophilic Leukemia, Not Otherwise Specified.