New study uses whole genome sequencing to diagnose rare diseases 

The study shows that whole genetic sequencing is a better way of diagnosing rare diseases than normal testing methods

Spotted: Your ‘Genome’ is all the information needed to make you. This information is written in a chemical code—DNA—which is broken up into thousands of sequences called genes. Malfunctions in these genes can cause disease. Doctors conduct genetic tests to search for these malfunctions – a task made difficult by the sheer number of individual variations that make up a person’s unique Genome. Most tests only look at a few genes, but whole genome sequencing (WGS), by contrast, looks at a person’s whole genome at once.

Now, a study published in the New England Journal of Medicine has found that WGS can help uncover new diagnoses for people with rare diseases. The findings of the study are believed to provide enormous benefits for the UK’s NHS, and healthcare systems around the world.

For the study, which was carried out by Genomics England and Queen Mary University of London in collaboration with the National Institute for Health Research (NIHR) BioResource, the genes of 4,660 people from 2,183 families were analysed. The goal was to see whether WGS would be better at diagnosing rare diseases than other conventional testing methods.

The results revealed that using WGS led to a new diagnosis for an impressive 25 per cent of the participants. Of this quarter, 14 per cent ‘were found in regions of the genome that would be missed by other conventional methods, including other types of non-whole genomic tests.’

Many of the participants in the study suffered from rare diseases and had undergone years of appointments, without getting any answers. This included a 10-year-old girl who had waited seven years for a diagnosis. The diagnosis from the study meant she was able to receive a curative bone marrow transplant.

The quarter of participants who received a diagnosis will now be able to receive more appropriate clinical care: further family screening, dietary change, provision of vitamins and minerals, and other therapies.

“Our novel software, together with collection of detailed clinical data, was key to us being able to solve the “needle in a haystack” challenge of finding the cause of a rare disease patient’s condition amongst the millions of variants in every genome,” explains Professor Damian Smedley, the study’s lead author.

Springwise has previously encountered commercial applications of WGS in the form of an app that offers it as a consumer product, and a service that provides users with tailored health news based on their uploaded genomic data. However, this new study is a major breakthrough for WGS as a clinical diagnostic tool.