The RAPSODI study: an online study to understand the association between the Gaucher-causing gene and Parkinson’s
By Naomi Limbachiya, RAPSODI study coordinator
Predicting the future
People with Gaucher’s disease are helping to revolutionise and expedite a new age of medicine that centres on prevention. For much time, science has concentrated upon the importance of accurately diagnosing illness, to help guide clinical decisions regarding treatment. Now, the focus has shifted towards preventing illness from developing and progressing. The idea behind this is to quantify early signs of disease progression and target the underlying mechanisms that cause them. Predicting the future is now considered an appropriate and achievable scientific endpoint.
The RAPSODI study
Over 100 people with Gaucher’s disease are part of the mission to accomplish just this, through the RAPSODI study. This is an online study which seeks to understand the association between the Gaucher-causing gene and Parkinson’s disease.
People with Gaucher’s disease have two copies of the GBA gene that are mutated. This means that someone with one mutated copy of the GBA gene will not have Gaucher’s disease but does have a small increased risk of developing Parkinson’s disease. This risk is very low, and research has found that the majority of those with one faulty GBA gene will not develop Parkinson’s disease. The aim of the RAPSODI study is to identify the reason for this discrepancy, to help develop neuroprotective treatments that will slow down and prevent Parkinson’s disease from developing in vulnerable carriers of the GBA gene.
The RAPSODI team acknowledge the importance of making research an enjoyable and comfortable experience for those involved. For this reason, the study is completely online, only requiring participants to have access to a keyboard and internet connection to take part.
Participants are asked to complete a series of questions and tasks measuring sleep, mood, memory, attention and movement. Participants also receive a saliva kit and smell test to complete at home and are requested to return this using a freepost envelope. The team use this saliva sample to identify changes in the GBA gene, along with another gene linked to Parkinson’s disease called LRRK2.
Importantly, all participants are given the choice as to whether they would like to be informed of their genetic results and whether they would like the team to notify their GP and clinician. Participants who would like to be informed of their results are given free genetic counselling by a member of the team. This involves discussing the exact change found and the implications that this may/may not have on a carrier’s relatives.
The team behind RAPSODI
The primary investigator for the study is Professor Anthony Schapira, a professor of neurology, the head of department of clinical and movement neurosciences at the University College London and an expert in the relationship between the GBA gene and Parkinson’s disease.
Professor Schapira said “The RAPSODI study was set up in 2016. It has been a great success and considerable thanks go to all those who have registered and participated. Particular thanks also to Stephen Mullin, Marco Toffoli, Soraya Rahall, Abbie Higgins, Naomi Limbachiya and Selen Yalkic who have made this project work and to Prof Hughes, Prof Mehta, Dr Moreno-Martinez and Alex Howard for their tremendous help and support.
“RAPSODI has enabled us to provide valuable insights into the relationship of changes in the GBA gene to the risk for developing Parkinson disease. This is due to the fantastic contribution of all those with GBA gene changes, as well as their family members and also those controls who have participated.
“Importantly, this work has laid the ground for the rapid development of new treatments that are now being tested in the clinic to prevent or slow Parkinson’s. Everybody’s contributions therefore have the potential to change a lot of lives for the better around the world.”
The team work alongside Professor Derralynn Hughes, who chairs the International Working group on Gaucher disease. She is a professor in haematology, the clinical director of research and innovation at the Royal Free London NHS Foundation Trust and an expert on Gaucher’s disease.
Professor Hughes describes the study as “a great opportunity for patients and physicians to understand more about the relationship between Gaucher and Parkinson’s and the opportunities to use this knowledge to develop new treatments”.
Dr David Moreno-Martínez, a senior lysosomal storage disorders fellow at Royal Free Hospital NHS, said “Through participating in the RAPSODI study, people affected with the variety of manifestations that stem from an alteration of the GBA gene are helping us to understand the mechanisms behind GBA-related Parkinson’s disease. The findings from this project might also impact the broader community, as people with non-GBA-related Parkinson’s disease, Gaucher’s disease and even other neurodegenerative diseases might benefit from them.
“Therefore, we are very grateful to all the participants for their help, as the data they provide us with is invaluable and will probably constitute the building blocks for future support for many people around the world.”
The study recruits those who have Gaucher’s disease, relatives/spouses of people with Gaucher’s disease, those who know they carry the mutated GBA gene, those with Parkinson’s and a mutated GBA gene and those who are relatives of those with Parkinson’s disease who carry a mutated GBA gene.
When asked why they participated in the study, one participant with Gaucher’s disease said “With Gaucher’s disease being so rare, I wanted to make sure that I could help other people and learn about new research developments that are upcoming.” Another participant stated that they joined the study “Because Gaucher’s disease is very rare, and I felt responsible to help in any way that I could.”
When asked how they found the RAPSODI assessments, a participant with Gaucher’s disease stated that “The assessments are perfect; there is nothing left out as everything that impacts your symptoms is included. There is a lot involved in Gaucher’s disease, including worrying about your future as well as your family, and the study covers everything”.
One participant with Gaucher’s disease expressed that what they value most about the study is “to know there is someone out there that cares about your condition and knows about it. I know that if I had any queries, I could just contact the RAPSODI team, and someone would give me positive feedback. And to know that other people with Gaucher’s disease are in the study, especially when it is so rare, is helpful. You check with our families how it impacts them, and this is important because the people that surround this condition are affected, and they have concerns and worries.”