The Guardian Australia

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.

Jonathan Roberts is a registered NHS genetic counsellor and postdoctor­al researcher at the Society and Ethics Research Group at the Wellcome genome campus

 ?? Photograph: Reuters ?? ‘While a genetic test may indicate the presence of a condition, it cannot give precise informatio­n about how severely that child will be affected.’ Genetic testing laboratory in China.
Photograph: Reuters ‘While a genetic test may indicate the presence of a condition, it cannot give precise informatio­n about how severely that child will be affected.’ Genetic testing laboratory in China.

Newspapers in English

Newspapers from Australia