Prader-Willi syndrome

Recommend to others!


Prader-Willi syndrome is a complex genetic disease, affecting many parts of the body. This condition is characterized, in childhood, by weak muscle tone (hypotonia), feeding difficulties, slowed growth and delayed development.

Since childhood, patients develop an insatiable appetite, which leads to chronic overeating (hyperphagia) and obesity. Some people with this syndrome, especially those who are obese, develop diabetes type 2.


1. Overview
2. Prader-Willi syndrome – signs, symptoms and characteristics diseases
3. Causes of Prader-Willi syndrome
4. Tests and diagnosis
5. Treatment

Prader-Willi syndrome – signs, symptoms and characteristics diseases

People with Prader-Willi syndrome have learning disabilities and intellectual level is somewhere between low and moderate. Behavioral problems are common and manifest by temperamental outbursts, stubbornness and compulsive behavior.

Many of those affected shows sleep disorders. In addition, people who suffer from Prader-Willi syndrome have distinctive facial features: short stature, small hands and feet, skin may be unusually white, hair will be light and genitals may be underdeveloped.

Puberty is delayed or incomplete and patients are unable to have children. Prader-Willi syndrome occurs in both men and women.

Causes of Prader-Willi syndrome

Prader-Willi syndrome is caused by the absence of genes in a particular area of chromosome 15. Normally, people inherit a copy of this chromosome from each parent. In some genes cases are activated only the copies inherited from the father, for example (paternal copy).

Specific activation of genes passed from parents is caused by a phenomenon called genomic imprinting. Prader-Willi syndrome occurs when missing paternal chromosome 15 region containing these genes.

Researchers are still trying to identify the genes on chromosome 15 that are responsible for Prader-Willi syndrome characteristics. They found that removing OCA2 gene from chromosome 15 is associated with unusually white skin and very light hair color to some of those affected, because protein produced by this gene helps determine the color of the skin, hair and eyes.

Most cases of the disease (about 70%) occur when a segment of pattern chromosome 15 is removed from each cell. In 25% of cases, people with Prader-Willi syndrome have two copies of chromosome 15 inherited from the mother instead of one copy from each parent.

Rarely, Prader-Willi syndrome may be caused by a chromosomal rearrangement called translocation, a mutation or other defect that inactivates genes found on the paternal chromosome 15. Each of these genetic changes results in loss of gene function in a critical region of chromosome 15.

- In the first stage, a child who suffers from Prader-Willi syndrome will have difficulty growing and will take excessive weight. The child will not be able to drink from glass and must learn special feeding techniques until his muscles get stronger. Children diagnosed with this condition are less developed than their peers with them.

- Children aged 1-6 years suffering from Prader-Willi syndrome develop a sudden interest for food and will begin to overfeed. It is believed that a child suffering from this condition will never saturate after a meal. Parents of children with this syndrome often try to restrict their children’s access to food, but at that age children take weight quickly.

Tests and diagnosis

In infants, signs that may determine the doctor to ask for blood tests to detect Prader-Willi syndrome include:
- Poor muscle tone
- Almond eyes
- Narrowing head in the temples.

In older children the doctor may suspect Prader-Willi syndrome if they manifest:
- Behavior problems
- Excessive weight gain.

A definitive diagnosis can be established by laboratory analysis. Special genetic tests can identify abnormalities characteristic for Prader-Willi syndrome in the child chromosome.


Most of the children with Prader-Willi syndrome require special care and treatment.

- Proper nutrition – Many children with Prader-Willi syndrome have difficulty feeding due to low muscle tone. The doctor may recommend a diet with more calories to help the child gain weight and monitor development.

- Treatment with growth hormones – growth hormone stimulates the growth and influence convert food into energy (metabolism). Some studies have found that growth hormone treatment in children with Prader-Willi syndrome help their growth, improve muscle tone and decrease fat tissue, but long-term effects of growth hormone treatment are not known.

- Hormonal treatment for normal sexual development – endocrinologist is likely to recommend hormone replacement therapy to restore low levels of sex hormones. In addition, hormone replacement therapy can help reduce the risk that a child presents to developing osteoporosis.

- Healthy diet – As your child grows, you should follow the advice of a nutritionist for a healthy development, to follow a low calorie diet so as to have a normal weight thanks to an adequate nutrition.

- General Development – The child will probably have a number of treatments:

> physiotherapy for motor skills to be developed and strengthened
> therapy to develop verbal skills and language
> occupational therapy.

It may be helpful the treatment for overall development support for the patient to dispose of behaviors, age-appropriate social and interpersonal skills.

- Mental health – A psychologist or psychiatrist will recommend treatment and therapy in order to solve the children’s psychological problems such as obsessive-compulsive disorder or mood disorders. Other treatments may be necessary depending on the specific symptoms that the child manifests or complications that may occur.



Speak Your Mind


Current day month ye@r *