Hox Genes: Literature Review and Clinical Overview of Human Defects and Cancer

In animals appendage placement and axial arrangement is dependent on four to forty-eight Hox genes. Hox genes are evolutionarily conserved because mutations are usually lethal, and the presence of Hox genes is evidence for common descent among animals. Experiments with Drosophila melanogaster (the common fruit fly) result in extreme defects when Hox genes are altered. Natural mutations in HOXA13, HOXA1, HOXA2, and other human Hox genes result in more subtle defects and abnormalities of the limbs, genitals, face, and inner-ear. New research suggests that Hox genes are involved in far more processes than initially thought, including oncogenesis. Understanding the role of Hox genes in oncogenesis could potentially be useful in developing therapies used to treat cancer.