not sure where this fits - cf carrier testing

[anonymous]

hi - my younger sister has cf, and unlike my extended family, i have not been tested to see if i am a carrier... my husband and i agree that i need to get tested, but neither of us know where to start, who to ask, and what to ask for. if there's any info i could get that would be fabulous. sorry to sound so uninformed, but i am.

catherine

 

[anonymous]

I was tested at my OBs when I found out that I was pregnant in April. It was a routne test that they do for all pregnancy's. I found out that I was a carrier and then my boyfriend had to be tested. We then found out that he was also a carrier. But we both had no other members of our family that we knew were carriers and we still have no idea what side it came from. We now have a one month old that does have CF.

 

[anonymous]

Some states automatically test, others do not. I live in a state which doesn't do carrier screening, so we didn't know DS had CF until a few weeks after he was born. Some states test the mother automatically and then if it's a positive test, they'll test the father. Being that you do have a family history, might be a good idea to request screening prior to planning a family.

 

[anonymous]

that's what i'm looking to do (pre-screen).... is there a particular test that is more effective than others to detect the various cf mutations? or is that something i even need to be concerned about when i get carrier tested.

catherine

 

[anonymous]

I believe they just test to see if you're a carrier. And several states test for several different genetic diseases, not just CF. If you're not a carrier, then I don't believe they'll suggest testing for your partner.

 

[anonymous]

Actually, if your sister knows which mutations she has, you can just request that you be tested for those mutations only. The testing should be cheaper and results quicker that way. Of course, this assumes that you both have the SAME biological parents - mother and father. Assuming that is the case, if you test negative for both mutations, then there is no need to have your partner tested. Even if he is a carrier, if you test negative, your children will at worst be carriers, at best be non-carriers.

If, however, you test positive for one or both mutations that your sister carries, then you should have your dh tested either through Quest's extended panel or Ambry's panel for all known mutations to ensure that he is not a carrier of any known mutations. THe genetic testing most drs offices use are just general screening tools and don't test for all mutations unless you specifically request, hence why you should request Ambry or Quest's extended panel.

If, however, you have a different biological parent than your sister (ie half siblings), then you should just request the full Ambry or extended Quest test to ensure the most accurate results possible.

Also, while Quest's extended panel and Ambry's panel test for all known mutations, there are still some unidentified mutations; therefore, it is at this time, impossible to conclusively rule out CF by genetic testing alone. The exception would be the case above - if you & your sister both have the same biological parents AND she knows BOTH of her mutations. In that case, if you test negative for both mutations, you are NOT a carrier for cf.

I hope that was helpful and not too confusing. Please ask if you have any other questions. Also, if you request the Quest test, be sure to specifically mention and double check with your dr that he/she does the EXTENDED panel since Quest has a brief carrier test, too that is used for the general population where there is no known family history of cf. (It tests for less than 100 mutations when there are well over 1000 known mutations.)

Good luck!!

 

[julie]

Catherine, glad to see you are so proactive about this!!!! I have a website that has the probabilities of inheriting CF, just wanted to post it in case the curiousity is there, but it won't be quite relevant until you and your husband do your carrier testing and find out the status. The link is <a target=new class=ftalternatingbarlinklarge href="http://www.cysticfibrosismaleinfertility.com/Where_to_begin_carrierTesting.html">http://www.cysticfibrosismaleinfertility.com/Where_to_begin_carrierTesting.html</a>

As far as the testing, most family practice doctors can order the testing. Is your sister a full or 1/2 sister? If she's full, you will know what potential mutations you would carry (granted, if she knows hers). If I were you, I would have yourself tested first and if the results reveal nothing, then testing your husband would be unnecessary but some would recommend it. If your sister doesn't know her mutations, I would recommend you request and extended panel test via Quest diagnostics. There are over 1000+ KNOWN CF mutations and more discovered all of the time. Here is a link to Quests website, <a target=new class=ftalternatingbarlinklarge href="http://www.questdiagnostics.com/hcp/topics/cf/cf.html">http://www.questdiagnostics.com/hcp/topics/cf/cf.html</a>. You could always go with a testing through Genzyme, but they only test for 25-89 of the most common mutations. If your sister has 2 common CF mutations then that's great, pretty easy to test you for. But if she's only had a sweat test, or had an extended muation test herself, I would recommend you just jump to the Quest test, especially with the family history of CF.

You aren't uninformed, don't feel bad. Not a lot of information is given about where people should begin with stuff like this. If you have any additional questions, please feel free to email me at division902@hotmail.com