Our mouse behavioral phenotypes are echoed in research describing patients with BP1-2 duplications (which include the CYFIP1 gene), noting that while half of BP1-2 duplication carries have developmental delay or speech delay [63], the phenotypes are highly variable, signifying that additional, unknown genetic modifiers may be necessary to cause ASD-associated deficits [12, 64]. This evidence concerns the gene CYFIP1 and Delayed speech and language development.