Prader – Willi
Syndrome
By Ria Gulati & Ami Bulsara
Period 4
Clinical Symptoms
•
•
•
•
Short stature
Poor motor skills*
Weight gain
Underdeveloped sex
organs
• Mild retardation and
learning disabilities
*motor skills: the ability to perform muscle-and-nerve acts that produce movement
Rare Symptoms
• Nearsightedness
• Light skin compared to
other family members
• High pain tolerance
• Skin picking
Problems Associated with Disease
• Constant feeling of hunger leads to obesity
• The overeating could become uncontrollable
and be life-threatening
Is it Common?
• common in all races
• However, in black patients,
growth is less affected
• About 1 in 10,000 to 1 in
15,000 people are affected
Mode of Inheritance
Is Prader – Willi Syndrome
autosomal or sex-linked?
Autosomal
Caused by a
Chromosomal Problem
• It is a chromosomal problem
caused when…
– Paternal genes on chromosome
15 are missing
– Inheritance of chromosome 15 is
twice from mother and none
from father
– Defect in paternal genes on
chromosome 15
Treatment of Symptoms
Weight management
Change of diet
Injection of hormones to
speed up hormonal
growth
Treatment of Gene Defect
There is no
treatment for this
gene defect
Is There a Cure? Gene Therapy?
There is no cure or
gene therapy available
at this point in time
Current Reseach
Prader – Willi Syndrome
Association funds research towards
•Obesity which is the #1 threat to PWS patients’ life
expectancy
•Respiratory which included pulmonary issues to
those with PWS
•Other which includes behavior, appetite suppressors,
brain imaging & functioning, etc.
Can PWS be Detected Prenatally?
Yes it can be detected while in the mother's womb
Diagnosis
• First, it is assessed by the clinic
• Then, it is confirmed by specialized genetic
testing on a blood sampling
Diagnosis (cont.)
DNA – based testing
determines whether the
Prader-Willi Critical Region
(PWCR) is maternally
inherited only
This process detects more than 99% of the
affected individuals
Carriers
Carriers cannot be detected!
?
?
?
?
?
?
Genetic Testing
People get it done in two types:
High Resolution Chromosomal Analysis
• Examination under a microscope
• It detects large deletions & other chromosomal
abnormalities
Genetic Testing (cont.)
FISH
• Stands for fluorescence in situ hybridization
(often done at the same time as chromosome
analysis)
• This test detects all common or typical
deletions
Quiz Questions
1. What are two clinical symptoms of PraderWilli Syndrome?
2. What are two rare symptoms?
3. What is the mode of inheritance?
4. Name one treatment of symptoms.
5. Can Prader-Willi syndrome be detected
prenatally?
Answers
1. Poor motor skills, mild retardation and
learning disabilities
2. Nearsightedness, high pain tolerance
3. Autosomal
4. Weight management
5. Yes
Works Cited
"Developmental Disabilities." Volunteers of America of Oklahoma. Web. 24 Mar.
2010.<http://www.voaok.org/Services/DevelopmentalDisabilities/tabid/3236/
Default.aspx>
"Genetics of PWS." Prader-Willi Association (USA). Web. 28 Mar. 2010.
<http://www.pwsausa.org/syndrome/Genetics_of_PWS.htm>.
"Prader-Willi Syndrome." GeneTests. Web. 28 Mar. 2010.
<http://www.geneclinics.org/profiles/pws/details.html>.
"Prader-Willi Syndrome - Genetics Home Reference." Genetics Home Reference Your Guide to Understanding Genetic Conditions. Web. 28 Mar. 2010.
fffff<http://ghr.nlm.nih.gov/condition=praderwillisyndrome>.
"Prader-Willi Syndrome - Labhart-Willi Syndrome - Information Page with
fdffffHONselect." Health On the Net Foundation. Web. 24 Mar. 2010.
fdfdf<http://www.hon.ch/HONselect/RareDiseases/EN/C10.597.606.
643.690.html>.
"Prader-Willi Syndrome: EMedicine Pediatrics: Genetics and Metabolic Disease."
EMedicine - Medical Reference. Web. 23 Mar. 2010.
xcdf<http://emedicine.medscape.com/article/94795z4-overview>.
Works Cited (cont.)
"Prader-Willi Syndrome: Treatment, Symptoms, Prevention, Cause, Risk,
hjhjhjComplications, Long-term Outlook." MamasHealth.com: Simple, Easy to
Understand Information about Health. Web. 23 Mar. 2010.
gjgjgj<http://www.mamashealth.com/syndrome/prader.asp>.
"QUESTIONS AND ANSWERS ON PRADER-WILLI SYNDROME." Prader-Willi
gjgjgjAssociation (USA). Web. 28 Mar. 2010. <http://www.pwsausa.org/faq.htm>.