The symptoms associated with this syndrome are variable, but common features include: low birthweight, low muscle tone at birth, poor feeding in infancy (often requiring feeding by tube for a period) and oromotor dyspraxia together with moderate developmental delays and learning disabilities but amiable behaviour. Other clinically important features include epilepsy, heart defects (atrial septal defect, ventricular septal defect) and kidney/urological anomalies. Silvery depigmentation of strands of hair have been noted in several patients. With age, there is an apparent coarsening of facial features. 17q21.3 was reported simultaneously in 2006 by three independent groups, with each group reporting several patients, and is now recognised to be one of the more common recurrent microdeletion syndromes. In 2007, a patient with a small duplication in same segment of DNA was described. An overview of the clinical features of the syndrome, by reviewing 22 individuals with a 17q21.31 microdeletion, estimated the disorder is present in 1 in every 16,000 people.
Koolen–De Vries syndrome
Urbach–Wiethe disease
Van Den Bosch syndrome
Van der Woude syndrome
Van Gogh syndrome
Baggio–Yoshinari syndrome
Barakat-Perenthaler syndrome
Aagenaes syndrome