How high is the risk of CF-pregnancy?

Question

I am pregnant and the 3rd child of the cousin of my husband has now CF (both children before have also the gene but are not ill). I am now very afraid that my child has that, too. What can I do? My first child has nothing and in our family there is nothing known about disability or inheritable diseases. Can one do a test to me or to my husband if one of us also carries the gene (I thought that we both have to have it in order to bequest it) as I do not want to have an amniocentesis done unnecessarily. How can one test it? Thanks,

Answer

Hello dear questioner,

first of all I want to gratulate to your second child. We are delighted for you that your family grows and we wish you all, all the best.

Now to your question. A genetic investigation is possible in your case. Taking the blood sample can take pace via your general practitioner and it can be sent to a human genetic institute [translators comment: the following provided addresses were in Germany]. In the accompanying letter the genetic result of the affected relative should be communicated if possible. The investigation of the blood should then be performed with your sample and the one of the father of your child. Only in case a CF-gene would be detected in both healthy parents (you and your husband are healthy,we speak then of a carrier of the illness), there is a probability of the occurrence of the illness. In case only one parent should be carrier of the illness, CF can not occur in the offspring. In case of healthy parents, who come out to be gene carriers for CF in the genetic test, the risk of getting an ill child is 25% in each pregnancy, in 50% the child can be a healthy carrier of the illness and in 25% the child can be healthy without having any genetic carrier material. After having the result of your genetic analysis, I would in any case recommend to have a genetic couselling in an instute for human genetics near your home. The costs for the human genetic testing and the following genetic counselling in an institue for human genetics are in general covered by the insurances of affected familes (cases of CF among relatives).

Yours sincerely,
Dr. Christina Smaczny

08.06.2011