Genetic testing boosts detection of foetal abnormalities

4 February 2019 (Last Updated February 4th, 2019 10:26)

A team of researchers in the UK has studied the use of genetic testing to better detect abnormalities in developing babies which are identified during ultrasound scans.

Genetic testing boosts detection of foetal abnormalities
Genome sequencing results in the pregnancy timeframe are expected to aid additional diagnosis that can support care. Credit: Heather Mount on Unsplash.

A team of researchers in the UK has studied the use of genetic testing to better detect abnormalities in developing babies which are identified during ultrasound scans.

The team included scientists from the Wellcome Sanger Institute, University of Cambridge, University of Birmingham, Great Ormond Street Hospital (GOSH) and their partners.

Findings showed that genome sequencing could improve the diagnoses of abnormalities identified by ultrasound by approximately 10%.

“When the team carried out whole-exome sequencing on DNA samples from 610 pregnancies involving babies with identified abnormalities, new diagnoses of known genetic disorders were detected in 52 cases.”

The researchers said that without genomic information, these abnormalities may not have been detected until after pregnancy.

They believe that providing the genome sequencing results in the pregnancy timeframe would aid the additional diagnosis that can support care, counselling and the family’s decision-making.

When the team carried out whole-exome sequencing on DNA samples from 610 pregnancies involving babies with identified abnormalities, new diagnoses of known genetic disorders were detected in 52 cases.

The genetic diagnoses were observed to be more common in foetuses with heart defects, skeletal abnormalities or multi-organ problems. This finding is expected to enable certain ultrasound findings that can be prioritised for genetic testing.

GOSH Genetics and Fetal Medicine professor Lyn Chitty said: “The study shows that genome sequencing improves the diagnosis of genetic conditions in developing babies who have been found to have structural abnormalities during a routine ultrasound.

“Making these results available during pregnancy means we can offer better counselling to parents and enable access to appropriate care. The next step is to work on implementing this approach nationally so more families can benefit.”

The research is part of the Prenatal Assessment of Genomes and Exomes (PAGE) study, which is designed to gain better insights into genetic alterations in order to improve prenatal diagnostics and genetics-derived prognoses.