Prader-Willi syndrome


What is Prader-Willi Syndrome?

Prader-Willi syndrome (PWS) is a rare and complex genetic disease. PWS affects the whole body. When babies are born with Prader-Willi syndrome, they have low muscle tone (hypotonia), problems feeding, poor growth (failure to thrive), and developmental delays. Baby boys usually have undescended testicles.

Unlike babies with Prader-Willi syndrome, children with Prader-Willi syndrome are unable to feel full when they eat, so they have the urge to eat all the time (hyperphagia), which leads to severe and often life-threatening obesity as well as other related conditions, such as type 2 diabetes, high blood pressure, and heart disease. Individuals with Prader-Willi syndrome also tend to have decreased levels of hormones that control the development of secondary sexual characteristics, which leads delayed or absent puberty and typically also to infertility.

People with Prader-Willi syndrome can also be shorter than average (small stature) and typically have small hands and feet. Mild-to-moderate learning difficulties and intellectual disabilities are common, as are certain behaviors, such as obsessive-compulsive disorder, poor mood control, and stubbornness.

SOURCE: Emory University - Department of Human Genetics in collaboration with ThinkGenetic • • DATE UPDATED: 2016-06-18


"Prader-Willi Syndrome (PWS): Overview" Eunice Kennedy Shriver National Institute of Child Health and Human Development. National Institute of Health. June 2014. Accessed February 1, 2016.

"Genetics Home Reference: Prader-Willi syndrome" National Library of Medicine. National Institute of Health. June 2014. Updated 1 February 2016.

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