Cystic Fibrosis

Question

Hello,
we have 3 daughters, the one in the middle died 1976 at the age of 5 years of Cystic Fibrosis. The two other children are healthy. The oldest daughter has two healthy children. The youngest daughter would also like to have children.
My question: As my wife and I are carriers of the illness, we probably have transmitted the illness. One of my daughters could therefore also be a carrier. Are there any possibilities today that one can assess if my daughter is also a carrier of the illness before the beginning of a pregnancy or is it only possible to make the diagnosis during pregnancy?

Thank you very much for your answer,
Yours sincerely,

Answer

Dear questioner,
the probability to be carrier for CF is 66,7% (2/3) for each of your daughters. With a molecular genetic investigation, it is possible to precise this probability (to assure being a carrier or probably to rule it out). For this aim it would be necessary not only to investigate the DNA genetic material from your daughter but probably also from you and your wife. If it is possible to show that your daughter has neither inherited your mutation of the CFTR-gene, nor the mutation of your wife, then she will not have children suffering from CF. If the investigation shows that your daughter is a carrier of a mutation of the CFTR-gene, an investigation of the partner of your daughter would be possible, in order to assess his staus of being a carrier.
I would advise your daughter a genetic conselling at a specialist for human genetics in oder that the possibilities and limits of a molecular genetic investigation can be explained explicitly to your daughter.
Specialists for human genetics are available at any university hospital and at many large hospitals or in a private office (look at the "yellow pages" of the telephone book). It is advisable in any case to get advice before a pregnancy and probably have a molecular genetic investigation being done.

Yours sincerely,
Dr. M. Stuhrmann-Spangenberg

20.11.2008