DLX5 and autism: The human DLX genes are organized as bigene clusters on chromosomes 2q31.1 (DLX1/2) and 7q21.3 (DLX5/6) and their expression is controlled by intra- and extragenic enhancers [27-30] These genes are close to loci that have been linked with autism (2q32, and 7q22-31) [31-34].