The role of gene duplication in the evolution and function of the vertebrate Dlx/distal-less bigene clusters.

ABSTRACT

The Dlx gene family controls developmental patterning principally in the pharyngeal and cranial regions. We review the structure and function of these genes in the vertebrates and relate these properties to their evolution. We particularly focus on the Dlx3-7 bigene cluster which we postulate to be more derived phylogenetically and functionally than the other two bigene clusters, Dlx1-2 and Dlx5-6. We stress the transcriptional control of the Dlx3-7 bigene cluster, and postulate its control by Dlx1-2.