Table 1.

Phenotype comparison of four rare chromosomal disorders and one monogenic Mendelian disorder reveals strong similarities and overlapping psychiatric symptoms^a

Genetic abnormality	PWS			VCF	SMS
	del 15q11	del 15q13.3	del 10q26	del 22q11	RAI1 (17p11.2)
OMIM	#176270	#612001	#609625	#192430	#182290
Depression	X	X		X	X
Rapid mood swings	X	X	X	X	X
Irritability	X				X
Hyperactivity		X	X	X	X
Impulsivity	X	X			X
Aggressiveness	X	X	X		X
Self-injurious behavior					X
Sleep disorder					X
Circadian abnormalities					X
Attention deficit	X	X	X	X	X
OCD	X	X		X	X
Anxiety disorders		X		X
Psychosis	X	X		X
Learning disability			X	X	X
Mild intellectual disability	X	X	X	X	X
Moderate intellectual disability	X	X	X	X	X
Severe intellectual disability		X	X	X
Language delay	X		X	X	X
Autistic features	X	X	X	X
Seizure disorders	X	X			X
Obesity	X				X
Cardiac abnormalities		X	X	X
Urogenital abnormalities			X
Endocrine abnormalities	X			X
Skeletal abnormalities	X	X	X		X
Facial abnormalities	X	X	X	X	X
Frequency	1:22,000	1:22,000	Unknown	1:2,000	1:15,000

Notes:

^aChromosomal deletion syndromes and monogenic Mendelian disorders share many symptoms with psychiatric disorders, even though the disease course is not specific for any one single disorder. The presence of intellectual disability, facial abnormalities, and neurologic symptoms could indicate a genetic syndrome rather than a common complex psychiatric disorder.

Abbreviations: OCD, obsessive–compulsive disorder; OMIM, Online Mendelian Inheritance in Man; PWS, Prader–Willi syndrome; RAI, retinoic acid-induced 1 gene; SMS, Smith–Magenis syndrome; VCF, velo–cardio–facial syndrome.