The 15q duplication syndrome (dup15q) refers to a number of related conditions.
Location: 15q11.2 to q13.1 in the Prader-Willi/Angelman critical region (PWACR)
Change: at least one extra copy of the PWACR derived from the mother (trisomy or tetrasomy). Trisomy occurs when there is an interstitial duplication within the maternally derived chromosome. Tetrasomy occurs when there is a supernumary chromosome with 2 copies of the region derived from the maternal chromosome.
Clinical features:
(1) hypotonia with onset during infancy
(2) motor delays
(3) intellectual disability, speech and language delays, developmental delay
(4) autism spectrum disorder or emotional lability, rarely psychosis
