CUL4B and syndromic intellectual disability: As both BRWD3 and CUL4B are part of the same complex it is likely that alterations of BRWD3 influence the ubiquitin-proteasome system similarly to other intellectual disability syndromes, whose prototype is represented by the Angelman Syndrome which is caused by mutations of the ubiquitin ligase-encoding UBE3A gene (MIM 105830).