Genetic counselling after carrier detection by newborn screening when one parent carries ΔF508 and the other R117H
- 1Genetic Health Services Victoria, Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Victoria, Australia
- 2Department of Respiratory Medicine, Murdoch Children’s Research Institute
- Correspondence to:
Ms L Curnow, Genetic Health Services Victoria, 10th Floor, Royal Children’s Hospital, Flemington Rd, Parkville Victoria 3052, Australia;
lisettecurnow{at}murdoch.rch.unimelb.edu.au
- Accepted 17 January 2003
Abstract
Newborn screening (NBS) for cystic fibrosis (CF) has been carried out in Victoria, Australia since 1989. The primary screen is immunoreactive trypsinogen (IRT) followed by ΔF508 mutation analysis. As part of this process, carrier babies are detected and their parents are routinely offered carrier testing as part of their follow up. The ΔF508 parent is identified and the other parent has an extended mutation analysis performed in case they are also a carrier. One of the mutations in the extended analysis is R117H which is associated with a broad phenotypic range, from CF with suppurative lung disease, to no clinical disease. We present four healthy ΔF508 carrier babies identified by our NBS service with both parents identified as carriers, one ΔF508 and the other R117H. Owing to the variable phenotype associated with R117H we have developed an approach to this difficult genetic counselling situation. Centres offering or considering NBS for CF will need an approach to this problem.
- CF, cystic fibrosis
- CFTR, cystic fibrosis transmembrane conductance regulator
- IRT, immunoreactive trypsinogen
- NBS, newborn screening
- cystic fibrosis
- genetic counselling
- newborn screening
