In every pregnancy there is a chance that a child may be born with a genetic condition, even where both parents are perfectly healthy. Often without knowing it, most people are carriers of one or more so-called recessive conditions Each one of these conditions is rare, but if both members of a couple happen to be carriers for the same condition, then any child born to them has a 1 in 4 chance of having the condition. If we group hundreds of rare conditions together then about 1 in 150 couples will both be a carrier for the same rare condition. Expanded carrier screening uses new technologies to group many conditions together and tell couples whether they are both carriers of the same serious genetic condition. Couples can then make informed decisions about what to do about this increased risk.
Carrier screening for 50 serious hereditary conditions
The UMCG developed a test that screens for 50 serious hereditary conditions, most of which have an early onset and cannot be treated. Following public consultation and preliminary research, general practitioners were considered to be in the best position to offer the test to couples prior to conception. In this study, the couples were offered couple results only, that is, whether they were both carriers of the same condition, and not whether either one of them was.
Is it responsible to offer such a test?
Schuurmans found that such carrier screening offered through GPs and disclosed as a couple result satisfied the criteria for responsible implementation. The study involved 190 couples in Groningen, Friesland and Drenthe, all hoping to conceive. Of these 190 couples, 117 went ahead and took part in the screening. GPs, who received targeted training to deliver this test, were well motivated and able to provide the relevant information about the test and guide their patients through the process. Most participants considered they could make a well-informed decision about taking part and negative psychological outcomes were absent regardless of whether they opted for the screening or not. They were also happy to receive the results as a couple.
Offering screening to all couples hoping to conceive
According to Schuurmans, the study shows that it may now be possible to offer the UMCG test to all couples via their GP. Schuurmans: ‘The next step will be to set up a large-scale, nationwide study of the introduction of this screening. All couples in the Netherlands hoping to conceive could be offered this screening, with longer term follow-up than this study was able to provide, to monitor effects on couples and the decisions they make after finding they are a carrier couple. It is important to study the long-term societal implications at the same time. A pilot study following the Groningen model is currently being run in Australia. It is being funded by the government and 10,000 couples are taking part.
Research in two English fertility clinics
The UK arm of Schuurman’s PhD took place in the Faculty of Medicine at the University of Southampton. Schuurmans studied the offer of carrier screening at two fertility clinics noting the difference in what it is to be a ‘couple’ in this setting, especially when donor eggs or sperm are used. The study explored health professional views about the offer, and the ethical aspects involved. Health professionals wondered whether the donors should be informed about their individual results since the nature of the couple here was so different. They considered this information to be relevant for potential future pregnancies with other partners or donors. However, the expanded screening test can easily be repeated when a new couple is formed and so individual carrier states becomes less important.
Curriculum vitae
Juliette Schuurmans (Den Bosch, 1989) studied Medicine at Utrecht University. She conducted her research in the Genetics Department and the SHARE Research Institute of the UMCG, and with the CELS research group in the Faculty of Medicine at the University of Southampton. Her thesis is entitled: Population-based Expanded Carrier Screening Reporting Couple Results Only: A Mixed Methods Approach. Her work was supervised by Prof. I.M. van Langen, Prof. A.M. Lucassen, Prof. A.V. Ranchor, Dr M. Plantinga and Dr A. Fenwick. She now works as a resident in the Clinical Genetics Department of UMC Utrecht.