Q: I know PWS is a genetic syndrome, so does that mean it runs in your family?
A: Short answer, no. You have to know by now though, that I can't leave it at the short answer. I am compelled to explain. ha!
PWS is genetic in that it occurs as a result of her genes. The most common way for PWS to occur is by a small deletion on the 15th chromosome. That piece that should have been donated from dad was just lost way back in the beginning when cells divided. In Ayden Jane's case, there were 3 pieces (trisomy), 2 identical pieces of my chromosome and the one from dad. Since trisomy in that particular region is "not compatible with life" the extra is kicked out. Only in Ayden Jane's case the 'extra' was daddy's so she actually has two momma chromosomes in that little spot. (there is one other way but I will come back to that)
The result of both of these is that every cell in her entire body is missing this tiny piece. It is a very complicated region which helps to direct the hypothalamus and control temperature regulation, sleep cycle, energy balance, satiety, hormones, endocrine system .... okay so now you realize what Ayden Jane and her friends are up against!
In both of these forms of PWS (called deletion and UPD) the PWS just a random occurrence. It occurs in approximately 1 out of every 12 or 15 thousand births. Nothing we did caused it and there would be no greater risk of it happening again if we were to have another child. (NOT happening)
The only way that PWS can be an inherited syndrome is in a specific portion of cases where it is caused by an imprinting error. All the correct pieces are there but they are turned off. If a child has PWS by imprinting defect it is best to discuss with a geneticist if they are the very small portion that are at higher risk for future children to also be born with PWS.
A: Short answer, no. You have to know by now though, that I can't leave it at the short answer. I am compelled to explain. ha!
PWS is genetic in that it occurs as a result of her genes. The most common way for PWS to occur is by a small deletion on the 15th chromosome. That piece that should have been donated from dad was just lost way back in the beginning when cells divided. In Ayden Jane's case, there were 3 pieces (trisomy), 2 identical pieces of my chromosome and the one from dad. Since trisomy in that particular region is "not compatible with life" the extra is kicked out. Only in Ayden Jane's case the 'extra' was daddy's so she actually has two momma chromosomes in that little spot. (there is one other way but I will come back to that)
The result of both of these is that every cell in her entire body is missing this tiny piece. It is a very complicated region which helps to direct the hypothalamus and control temperature regulation, sleep cycle, energy balance, satiety, hormones, endocrine system .... okay so now you realize what Ayden Jane and her friends are up against!
In both of these forms of PWS (called deletion and UPD) the PWS just a random occurrence. It occurs in approximately 1 out of every 12 or 15 thousand births. Nothing we did caused it and there would be no greater risk of it happening again if we were to have another child. (NOT happening)
The only way that PWS can be an inherited syndrome is in a specific portion of cases where it is caused by an imprinting error. All the correct pieces are there but they are turned off. If a child has PWS by imprinting defect it is best to discuss with a geneticist if they are the very small portion that are at higher risk for future children to also be born with PWS.
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