Optimising EXome PREnatal Sequencing Services

Watch this video for a simple introduction to diagnostic genetic testing in pregnancy

The optimising EXome PREnatal Sequencing Services (EXPRESS) policy report outlines actions to strengthen clinical implementation of, and further research on, prenatal exome sequencing services in the NHS. It explores the opportunities and challenges in establishing a new genetic testing service and captures key findings, including the views of parents and healthcare professionals. 

Why is prenatal exome sequencing needed? 

Fetal anomalies occur in approximately 2-5% of pregnancies and these are usually detected at the 20-week scan. A range of genetic tests can be carried out during pregnancy to determine if there is a genetic cause, however the majority – over 60% – are undiagnosed using these methods. Exome sequencing, which examines the 1-2% of the genome that encodes proteins, is a powerful approach where many genes can be examined with a single test, and can improve diagnostic rates. 

Developments in rapid sequencing pathways and the ability to deliver test results quickly enough to support clinical management of a pregnancy led, in 2020, to the NHS Genomic Medicine Service introducing a prenatal exome sequencing service in England. The EXPRESS study was a collaborative research study which explored the implementation of this service. 

Key findings and recommendations

The EXPRESS study found that parents and healthcare professionals welcomed the introduction of the service, and that good communication and close working between different groups of professionals supported successful implementation. 

Our report outlines recommendations for service delivery and future research opportunities. These include: 

• Further support for parents during and after testing, and healthcare professionals in terms of administration
• Workforce development – both the staff required to deliver services and their education
• Development of guidelines on use of prenatal exome sequencing, including essential pathway components
• Pathway audit and further development – where can pathways be streamlined, and delivered optimally
• Further research into the views of parents, particularly those from more diverse backgrounds and underserved populations. 

Read The optimising EXome PREnatal Sequencing Services (EXPRESS) policy report to find out more.