====== Prader-Willi Syndrome ======

====Main Features====
  * Neonatal
    * Neonatal hypotonia
    * Failure to thrive
    * Genital hypoplasia
    * Hypopigmentation of the skin, iris, and hair
  * Childhood
    * Excessive eating and gradual development of morbid obesity
    * Delayed Motor milestones and language development 
    * Cognitive impairment

====Eye Findings====
  * decreased visual acuity
  * iris and choroid hypopigmentation
  * refractive error
    * Myopia 40%
    * Hyperopia 25%
    * Astigmatism 25%
  * Amblyopia 16%
  * Strabismus 40%
    * congenital ocular fibrosis syndrome
  * cataracts
  * diabetic retinopathy
  * nystagmus
  * congenital ectropion uvea
  * Signs of oculocutaneous albinism can occur if deletion of the OCA2 gene which is found in the PWS critical region
====Other Findings====
  * Short stature and growth hormone deficiency
  * Delayed or incomplete secondary sexual characteristics 
  * Obesity complications
    * Sleep apnea
    * Diabetes mellitus
    * Atherosclerosis 
  * Epilepsy
  * Scoliosis
  * Behavioral problems and learning difficulties similar to autism spectrum disorder
  * Scoliosis
====Etiology====
  * loss of the paternal copy of chromosome region 15q11-q13
==== References ====
  * [[https://eyewiki.aao.org/Prader-Willi_Syndrome|EyeWiki Article]]
  * [[https://www.ncbi.nlm.nih.gov/books/NBK1330/#:~:text=Prader%2DWilli%20syndrome%20(PWS)%20is%20a%20complex%2C%20multisystem,short%20stature%20if%20untreated%20with|Gene Reviews]]

{{tag>syndrome}}