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Date of last update: 9/9/2017.

Forum Name: Pediatric Topics

Question: Prader-Wille syndrome

 Dawn 521 - Fri Dec 03, 2004 10:42 am

I have a handicapped son who shows signs of 100 percent prader but when the genetic fish test is done it says he is not geneticly is there other testing that can be done for prader wille or is it possible to have prader- wille and not test positive.?Our genetics doctor is very confused with the test result because like i said he is 100 percent prader.

Please help
 Dr. Heba Ismail - Sun Dec 05, 2004 3:39 pm

Dear Dawn,
In Prader-Willie Syndrome (PWS), if the FISH test comes back negative, the next step would be a test called the DNA methylation test. A relatively new test, DNA methylation can diagnose more than 99 percent of people with PWS, but it does not tell what could be the possible cause of PWS, so more testing is then needed. Sometimes, to confirm a suspected defect it may require testing in genetics laboratories specializing in PWS research.
 spaceghost1 - Fri Jan 20, 2006 3:42 am

My eldest sister had Prader Willie Syndrome. I would like to have children in the future, but I am afraid of having children with this defect. Who carries it? Mother? Father? and what tests are available to determine the carrier? Any info would be much appreciated. Thank you for your time! -AA
 Dr. Heba Ismail - Fri Jan 20, 2006 12:38 pm

Dear spaceghost1,
Prader Willi occurs when a baby fails to receive active genes from a specific section of the father’s chromosome 15 and there are three different ways by which this can happen.
You may wish to consult a genetics specialist, and there are now available a number of prenatal tests that can be performed for reassurance.

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