PCDHGC3 and autosomal dominant intellectual disability-craniofacial anomalies-cardiac defects syndrome: In Arboleda-Tham syndrome, there is a small DMR intergenic to most of the PCDHG genes in this cluster and positioned at the 5′ end of PCDHGC3. In Weaver syndrome there is a DMR with minor hypomethylation at the stretching from the same 5′ end of PCDHGC3 Arboleda-Tham that spans through to the shared 3′ end of PCDHG genes.