Cystic fibrosis and genetic screening: time for a conversation?
In recent years, the capacity of genetic medicine and technologies has expanded dramatically. A technique called whole genome sequencing (WGS), for example, using CRISPR technology, can relatively quickly and easily ‘sequence’ (or unravel) a person’s entire genome in order to look for genetic variants that might cause disease (now, or in the future) and even predict a person’s reaction to certain medicines.
Genomic sequencing such as this could also be used as a potential screening tool for the whole population, enabling people to make informed decisions about having children. For example, who they have children with, or even the genetic make-up of their future child. This type of reproductive genetic screening could be undertaken at three principal points in a couple’s reproductive journey:
1) Prior to conception (ie before pregnancy) to identify genetic carriers (potentially influencing who has children together).
2) During pregnancy to identify carrier status in the parents (and potentially also the foetus).
3) Shortly after birth to identify babies with genetic disease (as well as some carriers).
Whilst cystic fibrosis (CF) was added to the list of conditions that are screened for in all UK newborns (using the ‘heel prick test’) in 2007, these more recent developments in genetic medicine suggest that earlier screening tests (before or during pregnancy) are likely to eventually be available to the wider public as standard, regardless of known family medical history, to complement, and potentially replace, later screening tests.
This shift towards earlier tests is significant in genetic conditions such as cystic fibrosis. Whilst newborn screening facilitates earlier detection and treatment for babies with CF, pre-conception and pre-natal screening programmes may be used for possible earlier intervention and preparation for becoming a parent of a child with a life-limiting genetic condition. However, it may also be used to prevent the births of children with CF altogether, either by alerting carrier couples before they conceive or offering selective pregnancy termination to those couples with affected foetuses identified during pregnancy.
A preventative approach to screening like this has a variety of social and ethical implications. Whilst on the one hand, earlier tests may help future parents to make informed decisions about whether they feel they can cope with having a child with a condition like CF (thus increasing their reproductive freedom), on the other, it will also give people life-changing decisions to make about genetic conditions they are likely to have never encountered before.
How a person feels about the prevention of lives affected by CF through screening is likely to vary from person to person. However, very little research has been done to explore this. Where research does exist, this usually only reports on the views of the general public towards preventative screening and does not account for those who live closely with the condition.
Families and adults living with CF are important – if not the most important – stakeholder group in this debate. Affected families and adults, by virtue of them being experts on their own condition, are ideally positioned to consider how an earlier detection of CF may have impacted their own lives and decisions. Similarly, they will be able to reflect on how the introduction of preventative screening might affect them and their families, now and in the future.
The Cystic Fibrosis Screening Survey (UK) has been designed to ensure that the views of the CF community are accurately captured, explored and subsequently included in debates around preventative genetic screening. Given the surge of developments in genetic medicine such as CRISPR and the growing market for consumer genetic testing (such as AncestryDNA and 23andMe) along with the relatively recent appearance of campaign groups that are critical of screening practices (for example, the ‘Don’t Screen Us Out’ campaign in relation to Down’s syndrome screening), now is the time to start a dialogue around genetics and screening so that people living with the conditions that could be screened for not only have a voice, but one that will be heard before the debate and developments move on ever further ahead.