Genetic counselling will be key to help parents navigate changes in prenatal testing | Jonathan Roberts
As a genetic counsellor I try to help people make sense of genetics, inheritance and their family history. One important area is having conversations with parents who have an increased risk of having a child born with an inherited condition or disability.
While prenatal genetic testing has been available for many years, until recently this was only possible using invasive procedures, which carried small risk of miscarriage. Now a new technology – non-invasive prenatal testing (NIPT) – allows parents to have genetic testing with no miscarriage risk by testing fetal DNA that is circulating in the mother’s blood.
The test, now available on the NHS, is used alongside other established tests as a screening tool for chromosome conditions, such as Down’s syndrome. NIPT can also be used in a small (but growing) number of situations as a diagnostic tool for people who have a known inherited condition in their family.
More extensive testing – including whole genome sequencing (WGS) – is also now available in certain cases to help diagnose newborns who may have a genetic condition. While the first human genome took about 13 years to complete, technological advancements mean we now measure the turnaround in weeks, not years. As the technology continues to improve it has been suggested that tests could be carried out for all newborns.
These two technological advancements taken together mean that it is likely that many more people having children will be talking to professionals such as myself about what the result of genetic testing means for them.
When making decisions parents often want to know two things about the result of a genetic test. First, how confident are you in the result of this genetic test? Second, what will my child’s life be like with this genetic condition? Increasingly these questions are not easy to answer because information from WSG is not always certain as it may remain unclear if a genetic variant found is the cause of a condition.
An additional uncertainty is that, while a genetic test may indicate the presence of a condition, it cannot give precise information about how severely that child will be affected. Even people with the same genetic variant within the same family can experience it very differently.
A significant challenge is how to make decisions regarding what conditions we can test for. As technology improves we will be able to test for many more genetic conditions, but what will the cutoff point be? Life-ending syndromes such as Edwards’ syndrome, or learning disabilities and neurodivergence?
In this matter medical professionals are often guided by the ethical and legal frameworks that underpin abortion law, as well reproductive genetic technologies, which talk about prenatal genetic testing for “serious” or “severe” conditions.
This is a reasonable approach, but the severity of many disabilities is highly variable; and whether someone experiences a disability as moderate or severe – or even as a disability at all – can also depend on their personal experiences and how they have been treated.
Another issue is what to do when someone asks for testing for a condition that – from a medical perspective – might be considered “mild” but the patient has experienced as severe. An example might be parents making compelling arguments about the discrimination they have faced resulting from neurodiversity, and their desire to avoid this for their children.
There is an argument that by widely and routinely screening for genetic conditions we will create a kind of negative feedback loop. The fewer people born with disabilities, the fewer resources will be invested in research, health and social care. This will make life harder for people with disabilities, which in turn increases the pressure for people not to have children with certain conditions.
Disability rights campaigners have pointed to countries such as Denmark and Iceland that have seen increased screening lead to a reduction in the number of people born with Down’s syndrome. However, evidence is not conclusive that the introduction of non-invasive testing will lead to a high rate of terminations.
But perhaps an ethical implementation of these technologies isn’t about creating a categorical list of conditions that are OK to test and those that aren’t, but rather about attending to how people are making decisions. People need to be informed, free from pressure, free from judgment and supported emotionally. In this regard one of the big challenges will be having enough time to provide counselling in this depth. It is time and empathy that will allow people to pause, think and decide what is right for them.