The signs and symptoms of<unk>  vary widely. In addition to multiple osteochondromas and enlarged parietal foramina, affected individuals often have intellectual disability and delayed development of speech, motor skills (such as sitting and walking), and social skills. Many people with this condition have distinctive facial features, which can include a wide, short skull (brachycephaly); a prominent forehead; a narrow bridge of the nose; a shortened distance between the nose and upper lip (a short philtrum); and a downturned mouth. Less commonly,<unk>  causes vision problems, additional skeletal abnormalities, and defects in the heart, kidneys, and urinary tract.
Potocki–Shaffer syndrome
Lamb-Shaffer syndrome
Frey's syndrome
Banki syndrome
Upshaw–Schulman syndrome
Brown's syndrome
Wilkinson's syndrome
Kleine–Levin syndrome