ASXL1 Gene in AML

The ASXL1 (additional sex combs like 1) gene on 20q11 codifies the ASXL1 protein that belongs to protein complexes that play a role in gene expression and epigenetic regulation. ASXL1 is located near the DNMT3B gene and is part of a family of three genes (ASXL1, ASXL2, ASXL3) that are homologues to the Drosophila Asx gene. The ASXL1 gene contains a total of 14 exons and is expressed in the vast majority of hematopoietic cell types. While the specific job of ASXL1 in normal hematopoiesis and the involvement of mutated ASXL1 to the progression of hematopoietic malignancies have not yet been fully set forth, current data studies propose that ASXL1 is characterized as a tumor suppressor gene. Mutations in the ASXL1 gene are observed in myeloid malignancies usually associated with aggressiveness and poor clinical results and were reported first in the year 2009 in myelodysplastic syndromes (MDS). Nevertheless, ASXL1 gene mutations are also found in acute myeloid leukemia (AML) with normal karyotype as well as AML with myelodysplasia-related changes and AML with non-characteristic cytogenetic findings. Herein we examine the involvement of the ASXL1 gene in AML to address the importance of these ASXL1 mutations in the prognostic evaluation of AML.