TBR1 and Global developmental delay: Developmental disorders caused by mutations in GATAD2B (OMIM 615074) (54), ADNP (OMIM 615873) (55), BCOR (OMIM 300166) (56) and NR2F1 (OMIM 615722) (57) have features that overlap with those of TBR1-related disorder, including developmental delay, ID, speech and language impairments and autistic behaviors.