The main features of Prader-Willi syndrome are:
-
Early hypotonia (floppy body)
-
Severe feeding difficulties
-
Developmental delay
-
Later on in life over eating and obesity
-
Delayed puberty
-
Short stature
Genetic causes
80% of people with PWS have a deletion of chromosome 15 (a spontaneous deletion on the chromosome from the father). The other main cause is maternal UPD of chromosome 15. Rarer causes include imprinting problems on chromosome 15.
Useful Links
http://www.ncbi.nlm.nih.gov/books/NBK1330/
References
-
Cassidy, S. B. and D. J. Driscoll. "Prader-Willi syndrome." Eur.J.Hum.Genet. 17.1 (2009): 3-13
-
Sahoo, T., et al. "Prader-Willi phenotype caused by paternal deficiency for the HBII-85 C/D box small nucleolar RNA cluster." Nat.Genet. 40.6 (2008): 719-21.