What is Prader-Willi syndrome?

What is Prader-Willi syndrome?

• Prader-Willi syndrome: A rare genetic disorder characterized by reduced muscle tone, obesity and small hands and feet.
• Prader-Willi syndrome: A syndrome characterized at birth by the lack of spontaneous movements and protective reflexes, thus giving an appearance of severe brain damage. Profound hypotonia may cause asphyxia. Sucking and swallowing reflexes are absent or decreased. Deficient thermoregulation, amyotonia, and hypogonadism are usually associated. After a few weeks or months, the affected infants become more responsive and more alert. Areflexia disappears gradually but hypotonia may persist longer. This phase is marked mainly by mental subnormality, delayed growth and motor development, speech defect, lack of emotional control, voracious appetite leading to obesity, hypotonia, hyperlaxity, delayed bone maturation, and multiple orofacial and other disoders. There is a tendency to develop diabetes mellitus and cardiac failure in some patients. Pain insensitivity is common. Prader-Willi habitus associated with osteopenia and camptodactyly is known as the Urban-Rogers-Meyer syndrome.
  Source - Diseases Database

Prader-Willi syndrome is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Prader-Willi syndrome, or a subtype of Prader-Willi syndrome, affects less than 200,000 people in the US population.
Source - National Institutes of Health (NIH)

Ophanet, a consortium of European partners, currently defines a condition rare when it affects 1 person per 2,000. They list Prader-Willi syndrome as a "rare disease".
Source - Orphanet

Name and Aliases of Prader-Willi syndrome

Main name of condition: Prader-Willi syndrome

PWS, Willi-Prader syndrome, Prader Labhart Willi syndrome, Obesity, muscular hypotonia, mental retardation, short stature, hypogonadotropic hypogonadism, and small hands and feet

Labhardt-Willi-Prader-Fanconi syndrome Source - Diseases Database

Diminished fetal activity, obesity, muscular hypotonia, mental retardation, short stature, hypogonadotropic hypogonadism, and small hands and feet, PWS, Prader-Labhart-Willi syndrome, Willi-Prader syndrome
Source - Office of Rare Diseases (ORD) of the National Institutes of Health (NIH)

Types of Prader-Willi syndrome:

Parent types of Prader-Willi syndrome: Chromosome conditions, Imprinted chromosome conditions

How many people get Prader-Willi syndrome?

Prevalance of Prader-Willi syndrome: estimated 1 per 10,000 - 25,000 people suffer from Prader-Willi syndrome, Genetics Home Reference website
Prevalance Rate of Prader-Willi syndrome: approx 1 in 10,000 or 0.01% or 27,200 people in USA [about data]

How serious is Prader-Willi syndrome?

Complications of Prader-Willi syndrome: see complications of Prader-Willi syndrome

What causes Prader-Willi syndrome?

Class of Condition for Prader-Willi syndrome: genetic chromosomal
Causes of Prader-Willi syndrome: see causes of Prader-Willi syndrome

Can anyone else get Prader-Willi syndrome?

Inheritance: see inheritance of Prader-Willi syndrome

Inheritance of genetic conditions: see details in inheritance of genetic diseases.

How is it treated?

Treatments for Prader-Willi syndrome: see treatments for Prader-Willi syndrome
Research for Prader-Willi syndrome: see research for Prader-Willi syndrome