Williams syndrome

synonym: elfin facies syndrome
https://doi.org/10.1351/goldbook.11383

Congenital disorder with characteristic facies (described as elf-like), short stature, outgoing personality and mild mental retardation; associated with contiguous gene deletions on chromosome 7.

Source:
PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 821 (https://doi.org/10.1515/pac-2015-1202)