This Q&A is part of a series of articles for Rare Disease Day exploring the work in which BRC-funded researchers are involved. You can find our other articles here.

Dr Melita Irving trained in paediatrics before joining the clinical genetics department at Guy’s and St Thomas’ NHS Foundation Trust in 2000. She undertook a fellowship in skeletal dysplasia at the Royal Children’s Hospital, Melbourne, and has set up dedicated clinics in skeletal dysplasia and achondroplasia at Evelina London Children’s Hospital.

She is a consultant in the clinical genetics department at Guy’s and St Thomas’, which provides a service across south London, Kent and east Sussex.


I specialise in a branch of medicine called clinical genetics. My colleagues and I help to diagnose the risks to families of inheriting a particular disease and provide information on how that might affect them and their families – a service we call ‘genetic couselling’.

In recent years, my research has focussed on a skeletal dysplasia, or dwarfism. In particular, I have focussed on achondroplasia, the most common form of dwarfism, which affects one in 20-30,000 people.

While short stature is the most recognisable manifestation of Achondroplasia, the condition also carries with it a number of other potential complications and difficulties, such as neurological problems, bowed legs, joint problems, sleep apnoea and spinal cord compression. I am currently leading a multi-centre, multinational study in the UK to see whether a drug called Vosoritide could help to alleviate these problems.

Sam Short (right) with his mum Jen and brother Alex. Sam has Achondroplasia and is a volunteer on our trial at the Evelina London Children’s Hospital

World-class people and technology

Technological advances have made a huge impact on the study of all kinds of rare diseases. Here at Guy’s and St Thomas’ we have access to state-of-the-art clinical research facilities, technology and researchers which have helped to changed the pace at which discoveries have been made.

Searching for an individual gene that’s responsible for a particular condition used to be like searching for a needle in haystack without even being sure you were looking in the right haystack. The high-throughput sequencing machines at Guy’s and St Thomas’ give us a fast and cheaper way to analyse an extremely large number of genes quickly and simultaneously. This means that breakthroughs that used to take decades now take weeks.

We are extremely lucky to have the NIHR Biomedical Research Centre (BRC), which has not only invested in the research infrastructure but also helped us forge closer ties with our academic partner King’s College London.

In 2011, I was part of the team that discovered the gene responsible for the development of a rare form of severe childhood osteoporosis called Hajdu Cheney syndrome. The discovery was made possible thanks to the work of my team of clinical geneticists here at Guy’s and St Thomas’, researchers from KCL’s division of Medical and Molecular Genetics, and the state-of-the-art gene sequencing technology made available to us by the BRC.

Focussing on the detail to see the bigger picture

One of the most important changes in people’s attitudes to rare diseases has been the realisation that discoveries made in rare disease can have an impact on more common conditions.

Hajdu Cheney syndrome osteoporosis is so rare that personally I know many of the people in the world who have the condition. However, by discovering the individual gene behind that condition we have opened up a whole new focus for researchers looking into more common complex forms of the disease, such as the types that affect the elderly or people with cancer.

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