The Royal Devon University Healthcare NHS Foundation Trust is leading new research that builds on the findings of a revolutionary genetic study.  

Working in partnership with the University of Exeter, the research follows up on the impact of those diagnosed through the Deciphering Developmental Disorders (DDD) study. This cutting-edge research project has so far led to diagnoses for around 5500 people, with 60 new conditions discovered.

For Lisa Hawker, getting a diagnosis of her daughter Jaydi’s rare genetic condition was life-saving.

Jaydi has a rare form of dwarfism which affects around 50 known people across the world. Her early months were defined by long stints in hospital. She had a large number of tests which failed to identify the cause of her condition. Her clinical geneticist invited her parents to enrol her in an innovative national study, to try an identify the cause. She was four years old when a blood test showed very low numbers of blood cells. A bone marrow test showed her bone marrow wasn’t producing blood cells normally and her immunity was dangerously low. The doctors looking after Jaydi weren’t sure how best to manage her, but at almost the same time her genetic results from the largescale Deciphering Developmental Disorders study came in.

Dr Emma Kivuva, Jaydi’s clinical geneticist at the Royal Devon University Healthcare NHS Foundation Trust, said: “Jaydi’s results came at just the right time. They explained what was wrong with Jaydi, and this enabled her doctors to look after her appropriately. She was found to have a very rare condition that causes increased susceptibility to infection, and a greater risk of developing cancer, in particular leukaemia.”

The team advised a bone marrow transplant to significantly reduce Jaydi’s chance of developing leukaemia or a severe infection, and recommended additional vaccinations.

Jaydi’s mother Lisa, a single mum from Seaton, in Devon, said: “I really believe that if she hadn’t had that transplant, Jaydi wouldn’t be alive today. A simple cold could have killed her.”

The Hawkers are among 13,500 families, recruited from 24 regional genetics services across the UK and Ireland, to the Deciphering Developmental Disorders (DDD) study. The study is a collaboration between the NHS and the Wellcome Sanger Institute, funded by Wellcome and the Department of Health and Social Care, and supported by the National Institute for Health and Care Research Biomedical Research Centres in Exeter and Cambridge. 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.

All the families had children with a severe developmental disorder, which was undiagnosed despite prior testing through their national health service and likely to be caused by a single genetic change. The study has so far led to diagnoses around 5,500 people, with 60 new conditions discovered.

Now, new research involving clinical collaborators from all 24 recruitment centres has revealed that 28 per cent (1,183 people) of people in the study were able to change treatment or get further medical testing as a result of their diagnosis.

The study, published in the open-access journal Genetics in Medicine, also found that 76 per cent (3,214 people) of those diagnosed were given information or support specific to their condition. More than 20 per cent (880 people) joined patient support groups, such as Unique

Jaydi is among three per cent (143 people) who were able to start, review, stop or avoid specific therapies, which can have a major impact on quality of life, and can be lifesaving. Researchers expect this number would be greater in future, as new genetic therapies continue to develop.

For Lisa Hawker, the study has kept her “happy little girl” alive. Jaydi has overlapping conditions that mean she is non-verbal and has problems seeing and hearing, yet she lives life with a joyful energy. “She’s a total maniac,” her mother said. “She loves singing and dancing – she really is full of life. It’s so important to progress this research, because even finding people with the same condition for support is crucial. It makes you feel less alone. And for us, it saved Jaydi’s life.”

Read more about the findings on the University of Exeter website