Language evolution resulted from changes in our biology, behavior, and culture. One
source of these changes might be human self-domestication. Williams syndrome
(WS) is a clinical condition with a clearly defined genetic basis which results in a
distinctive behavioral and cognitive profile, including enhanced sociability. In this paper
we show evidence that the WS phenotype can be satisfactorily construed as a
hyper-domesticated human phenotype, plausibly resulting from the effect of the WS
hemideletion on selected candidates for domestication and neural crest (NC) function.
Specifically, we show that genes involved in animal domestication and NC development
and function are significantly dysregulated in the blood of subjects with WS. We also
discuss the consequences of this link between domestication and WS for our current
understanding of language evolution.