Thousands of children with severe developmental disorders have benefited from more targeted treatments and support with genetic insights from the large-scale Deciphering Developmental Disorders (DDD) study, finds a new study. Researchers from the University of Exeter and the Royal Devon University Healthcare NHS Foundation Trust followed up on the impact of those diagnosed as part of the DDD study, a collaboration between the NHS and the Wellcome Sanger Institute. This large-scale project, which began over a decade ago, has led to life-changing diagnoses for over 5,500 families across the UK and Ireland and the discovery of 60 new genetic conditions.

The findings, published in Genetics in Medicine Open (14 October), reveal that over a thousand of those diagnosed were able to alter their treatment or undergo further medical testing based on their genetic findings, significantly improving their quality of life. The Deciphering Developmental Disorders (DDD) study included 13,500 families, recruited from 24 regional genetics services across the UK and Ireland. All the families had children with a severe developmental disorder, which was undiagnosed despite prior testing and likely to be caused by a single genetic change.

The Wellcome Sanger Institute sequenced all the genes in the children's' and parents' genomes to look for answers, a search which is still ongoing. In this new study, researchers analysed outcomes for 4,237 of the families who received a genetic diagnosis , findi.