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2 mutations, diagnosis:carrier

Jennifer11

New member
my daughter was born 10 months ago. about a week after we got home from the hospital her doctor called and said we had to take her to Hershey to get a sweat test done because something in her bloodwork came back positive for CF. During my pregnancy I had found out I was a carrier, so my b/f went to get his bloodwork done at the same place, he came back negative. What they didn't tell me untill I was down in Hershey was that they only test for the 80 most common mutations. Well they couldn't get enough sweat from my daughter because of her age, so they did another heel prick. two weeks ago I got a call from the CF councelor from Hershey and since I was in NY at the time, she had told me on the phone that she was positive for the disease and to bring her down on the 20th to start treatments of albuterol. we go to Hershey and they give another sweat test and they got a result of 18 and 20, which is low/normal. her regular pediatrician said she was just a carrier of 2 genes and that was that. her hershey specialist left it as her being non-symptomatic as of yet. Is she a carrier of 2 genes (is that possible)? gene mutations DF508 and L997F
Jennifer

Jennifer 28:carrier
Piper 10 wks: carrier of 2 mutations(or so what the Dr. says)
 

kybert

New member
no, it is not possible. 2 mutations/genes = cf. no doubt about it. it is very irresponsible of the doctor to say that your daughter does not have cf when its clear she does. she just doesnt have any symptoms, yet. you need to find another doctor asap.
 

julie

New member
This is sort of complicated....... I'll try my hand at it.

There ARE cases of people who have 2 mutations on the same chromosome (chromosome 7). Theoretically, a child gets 1 chromosome from each parent but there are rare cases of a child getting 2 of the same mutations from 1 parent. This really only becomes noticable if there is some sort of genetic defect involved (i.e. CF), like if a child gets 2 "defective" CF mutations from a father on chromosome 7 and NO chromosome 7 from the mother (the father is a carrier, the mother is NOT a carrier of any of the mutations). Other times there have been cases of someone having 2 CF mutations on 1 chromosome (again very rare) and the other chromosome does not harbor a CF mutation. Many times, this person will have a negative sweat test but still have some CF involvement. This becomes even more complicated because CF affects everyone differently-even sibilings with the exact same CF mutations, even TWINS! Therefore, one person in the above situation might have a positive sweat test and classic CF symptoms, whereas another person in the above situation will have a negative sweat test and NO classic CF symptoms, and then another case where a person in the above situation has a negative sweat test but the DO have classic CF symptoms.

It use to be thought that the mutations of this disease and the accuracy of a sweat test were pretty cut and dry and were indicative of YES you have CF or NO you don't have CF. As medicine and technology advances, it is becoming clear that this is NOT the case.

There are also numerous cases (moreso than the scenario above) where a child will test negative for a sweat test but be positive for carrying 2 mutations-which means they have CF. Apparently there are some mutations that don't cause a sweat test to be positive because that person doesn't create all that excess salt that is traditional for a CFer. Regardless of whether or not you have your boyfriend tested, the fact remains that your daughter has 2 CF mutations and therefore she DOES have CF. Whether or not she will have a mild case of cf....???? Only time will tell. I can not understand why the doctors office told you that she is only a carrier, it is very clear that there is MUCH confusion about CF muations but a negative sweat test does not mean that somebody is "clear" of CF (or in your case "only a carrier of 2 mutations) when they have 2 mutations. BUT, if her 2 mutations are on the same chromosome, that is an entirely different story and there is a person on this site who's child is in that situation. I am not sure if they categoried her daughter as a carrier of 2 mutations or if she has any CF symptoms. The next step would be to determine if your childs 2 mutations are on each of the chromosomes OR if they are 2 mutations on the same chromosome. Honestly though, I am not sure what kind of symptoms a person with 2 mutations on the same chromosome has..... if they have classic CF symptoms and problems of if they are spared that, or if it is on a case by case (as everyone's CF affects them differently).

I would definately find a CF specialist (other than this clinic in hershey that she is being seen at now) who won't settle with telling you she is a carrier of 2 mutations until they do all the chromosome testing to determine that. It is somewhat irresponsible of the clinic to tell you that!!!

I realize this is all pretty complicated so I hope it makes sense,
 
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