Choroideremia is a rare eye condition that blinds men. It starts with not being able to see very well in the dark and leads to complete blindness 20 to 30 years after symptoms begin.
The condition is passed down through families. Tommy’s grandad had choroideremia and went blind at 48. His mother, Emma, was tested and is a carrier.
The disease is caused by a fault in one of the genes located on the X chromosome.
Women have two X chromosomes, so a healthy version of the gene on one of the chromosomes can compensate for a faulty gene on the other.
Men have one X chromosome (and one Y chromosome) which they inherit from their mother, so Tommy had a 50/50 chance of inheriting the condition.
As there is no treatment or cure, choroideremia results in blindness.
Choroideremia is caused by the degeneration of several layers of cells at the back of the eye that are essential for sight.
This is a result of a fault in the gene know as, CHM.
This specific gene produces a protein called Rab escort protein-1 (REP-1).
Without this protein the cells in the retina at the back of the eye slowly stop working and die off.
The first symptoms of the disease start in early childhood with trouble seeing at night or in dim light (night blindness).
As you age into your twenties and the disease progresses you develop 'tunnel vision' because your peripheral (side) vision goes.
Your ability to see clearly, judge depth and perceive colour also gets worse. You lose the ability to see detail.
Your sight get worse over time and leads to blindness normally around the age of 40.
Fight for Sight is the UK's leading charity funding research into preventing sight loss and treating eye disease.
Since 1965 our mission has been to stop sight loss in its tracks.
No eye problem is too big or too small for us to take on. By funding pioneering research, we’re creating a future everyone can see.
We currently have a commitment of £8.4million for over 150 projects at 35 UK universities and hospitals.
We’ve seen significant developments in stem cell and gene therapy research, treatments using lasers and new drugs, corneal transplants and the advancement of surgical techniques. We’re incredibly proud of our scientists and what they do every day.
Each year the we spend £3-4million on new research projects. All applications for funding are rigorously peer reviewed by international leaders in the relevant disease areas to ensure we are funding world class research.
Science, medicine and technology are rapidly coming together to bring us closer to preventing, treating and ultimately reversing sight loss. The pace of change has never been so exciting or so rapid.
Pioneering eye research
The Tommy Salisbury Choroideremia Fund at Fight for Sight provided £300,000 in funding for Professor Miguel Seabra at Imperial College London. Professor Seabra’s choroideremia research was significantly accelerated by the injection of funds. His research played a key role in identifying the function of the protein REP-1 causing choroideremia.
Professor Seabra went on to collaborate with Professor Robert MacLaren, Professor of Ophthalmology at the University of Oxford. Professor MacLaren received a grant of £1.1million to conduct the world’s first clinical trial of a treatment for choroideremia. Funding came from the Health Innovation Challenge Fund, a scheme supported by the Department of Health and the Wellcome Trust.
The clinical trial aimed to replace the faulty CHM gene with a healthy CHM gene. A harmless virus carrying the replacement healthy gene is injected underneath the retina. This virus acts as a transport mechanism carrying the replacement healthy gene into the light sensitive photoreceptor cells in the retina, which will then make the REP-1 protein.
In 2014, six months after treatment with this therapy, the first six patients reported that their vision had improved in dim light. Two of the six were also able to read more lines on the eye chart.
As a result of this successful trial a new company, NightstaRx was formed as a spin-out from the University of Oxford with £12million of investment from Syncona, a subsidiary of the Wellcome Trust. NightstaRx aims to bring gene therapies for inherited eye diseases to the clinic. Syncona later increased their investment to £17million and in November 2015 NightstaRx closed a second round of funding for $35million led by New Enterprise Associates, one of the world’s leading venture capital firms.
None of these significant advancements towards a treatment for choroideremia would have been possible without Emma, Tommy and Grandma Dot's ambition.
Together, with the help of family, friends, colleagues and other families affected by choroideremia, Emma, Tommy and Dot have fundraised tirelessly to help support vital research into the condition, organising numerous events such as golf days, coffee mornings and fun runs. In 2015 Emma was awarded Tesco Achieving Mum of the Year.
To date, more than £400,000 has been raised but Emma and Dot will continue fundraising until a treatment is available for Tommy.
Choroideremia is part of Tommy’s life but medical research has given real hope that his sight could be saved and the sight of others like him.
Emma, Dot and Tommy have shown us that there’s a pioneering spirit in every one of us.
We must continue the fight.
Watch our video below for more about Tommy’s story.