Moosajee Lab

Inherited retinal diseases (IRDs) are the commonest cause of sight loss amongst working age adults worldwide. These conditions can affect individuals at any age including young children. Prof Moosajee and her team are focused on the clinical characterisation of these conditions through undertaking natural history studies, establishing genotype-phenotype correlations, and structure-function relationships with advanced retinal imaging techniques in order to determine outcome metrics for clinical trials.

IRD disease models

In the lab, she has generated various disease models to understand the molecular basis of IRDs. Professor Moosajee’s team are one of only a few teams around the world who have mastered the techniques needed to grow retinal organoids and retinal pigment epithelium in the lab using patients own skin cells through induced pluripotent stem cell technology. Having this expertise allows the team to examine eye conditions incredibly accurately. By growing retinas in the lab with various genetic alterations, they have gained insight into how these affect the developing eye, how they cause certain conditions and, most importantly, how therapies could overcome these mutations. Prof Moosajee’s team have retinal disease models for USH2A, CRB1-retinopathies, RLBP1-retinopathy, PHARC syndrome, C1QTNF5- late onset retinal degeneration, RDH12 and GUCY2D.

Non-viral gene therapy for IRDs

Prof Moosajee’s team is developing new therapies for IRDs, that may be translated to patients in the future. Her main focus is the use of non-viral gene therapy approaches. This includes the delivery of specialised DNA plasmids that can hold genes of any size coupled with lipid nanoparticles, which help deliver the plasmids into the cells. Her team has already showed proof-of-concept that they can deliver small and large genes to the retina with long term gene expression. This has been tested for USH2A-retinitis pigmentosa (gene size is ~16 kb cDNA) and choroideremia (gene size 1.9 kb cDNA). The team are also working on delivering mRNA to the retina, also coupled with lipid nanoparticles. Both approaches avoid the use of viruses and hence any associated immune and inflammatory issues (gene therapy associated uveitis, GTAU) that are associated with conventional viral gene therapy.

To advance this work, as the reach is vast with clinical application to all IRDs, please donate to support the research of Professor Moosajee and her lab.

CRB1 is a gene that makes a key protein needed for correct development of the retina and maintaining adherence (through tight junctions) between photoreceptors cells in the mature retina. When mutations in this gene occur, it can result in a range of eye conditions that cause patients to progressively lose their sight, including Leber congenital amaurosis (LCA), retinitis pigmentosa (RP), cone-rod dystrophy and macular dystrophy. To date over 300 genetic mutations in CRB1 have been identified, but researchers have no clear understanding of how these mutations link to the different symptoms patients experience. As a result, there are currently no cures or treatments for any of these conditions.

Professor Mariya Moosajee and her team are on the cusp of changing this. At the forefront of vision research, they are now turning their attention to unpicking CRB1. To do so, they are growing ‘retinas in a dish’ that have different types of CRB1 mutations and examine their effects. The team are also developing new treatments including the deliver of healthy CRB1 mRNA to CRB1 retinal organoids to assess if they can rescue the disease.

• Donate to CRB1 research and bring us one step closer to developing much-needed treatments for patients with sight loss caused by CRB1 mutations.

A large programme of work in the Moosajee lab is dissecting the underlying molecular genetics both in terms of identification of novel genes and also characterising the mutation spectrum and prevalence in known genes of conditions affecting the development of the eye. This includes microphthalmia, anophthalmia and ocular coloboma, collectively known as MAC.

Prof Moosajee’s team have already discovered more than 7 genes (including NTN1, FADD, ANK3, BMPR1B, PDGFRA, and CDH4) that cause this spectrum of genetic eye disease. The team are also committed to understanding the disease pathophysiology of these conditions. They can grow early eye cups in a dish from patients and study how genes are working during eye development. Prof Moosajee’s team are also developing new treatments that can encourage eye growth postnatally for patients born with smaller underdeveloped eyes. 

There are several conditions that arise when the front anterior chamber of the eye doses not develop properly during pregnancy, these include anterior segment dysgenesis, aniridia caused by mutations in PAX6, WAGR syndrome, congenital glaucoma and cataracts. Prof Moosajee’s lab are researching these conditions. Molecular diagnostic rates are low compared to other genetic eye conditions, hence, her team are discovering novel genes and also characterising the mutation spectrum to establish genotype-phenotype correlations.

We have developed zebrafish and human disease models of aniridia using induced pluripotent stem cell technology to grow retinal organoids and corneal epithelium cells. We have been studying the disease mechanisms of PAX6 in the eye and systemically, through multi-omic approaches including whole metabolomic profiling and patient reported questionnaires. 

Jessica Alvarez
Jessica E. Alvarez S. is currently undertaking an MSc in Genomic Medicine at the William. Harvey Research Institute, Queen Mary University of London. She is a visiting researcher at the UCL Institute of Ophthalmology in Dr Mariya Moosajee’s laboratory, where she is gaining experience in retinal organoid culture and stem cell-based models of inherited retinal disease. She is also involved in research with the Marfan Trust on Neonatal Marfan Syndrome and inherited connective tissue disorders. Her interests include stem cell biology, genomic medicine, and inherited genetic diseases. Jessica is also a Research Technician at the William Harvey Research Institute, working ongenomic studies of heritable thoracic aortic aneurysm and dissection (HTAAD). She additionally contributes as a volunteer gene curator within the ClinGen Brain Malformations Gene Curation Expert Panel (GCEP). Her previous research experience includes stem cell models, microbiome genomics, and translational biomedical research in the UK and Mexico.

Dr Randa Li
I graduated from Edinburgh medical school and received my specialist ophthalmology training in Hong Kong. I am currently working as a clinical trials research fellow in Moorfields Eye Hospital. I am a sub-investigator for the Luna trial which is investigating the use of intravitreal Ultevursen, an experimental RNA therapy designed to slow or stop vision loss in people with Usher syndrome type 2a and retinitis (RP) caused by specific variants in exon 13 of the USH2A gene. My special interests are in translational research and delivering therapies for genetic eye diseases.

Mutian Lian
I am a PhD student at the UCL Institute of Ophthalmology in Professor Mariya Moosajee’s group. My research focuses on developing non-viral gene therapy strategies for inherited retinal diseases, with a particular emphasis on Usher syndrome type 2A. My PhD project investigates lipid nanoparticle (LNP)- mediated delivery of large DNA vectors encoding full-length human USH2A to photoreceptors, aiming to overcome the packaging limitations of conventional viral vectors. My work combines retinal organoid disease modelling, iPSC culture and differentiation, large plasmid and linear DNA vector design, lipid nanoparticle formulation, and molecular and imaging-based assessment of therapeutic efficacy. I am particularly interested in translating patient-driven genetic discoveries into clinically relevant therapeutic platforms for currently untreatable inherited retinal disorders. Before starting my PhD, I worked as a research assistant in Professor Moosajee’s group, where I contributed to projects involving iPSC-derived retinal organoids, non-viral gene delivery, and disease modeling for inherited retinal diseases. I am also actively involved in patient advocacy and have worked with inherited retinal disease communities to improve communication between patients, clinicians, researchers, and industry partners.

Maria Toms
I have a Zoology BSc from the University of Manchester and an MSc in Reproductive and Developmental Biology from Imperial College London. I completed my PhD in Molecular Genetics in Prof Moosajee’s lab at the UCL Institute of Ophthalmology. During this period, I investigated the pathophysiology of retinal diseases caused by USH2A and KCNJ13 mutations using zebrafish models. I am currently a research fellow based at The Francis Crick Institute and UCL Institute of Ophthalmology. The main focus of my research is the development of non-viral retinal gene therapy for large genes like USH2A, using DNA vectors packaged into lipid nanoparticles. I am also involved in several other interesting projects including the validation of micropthalmia, anophthalmia, & coloboma (MAC)-associated gene candidates using zebrafish, and investigating potential therapeutic strategies for choroideremia using zebrafish and murine disease models.

Dr. Jose Antonio Aragon-Martin 
Dr. Jose Antonio Aragon-Martin is a Research Fellow in Professor Mariya Moosajee’s group at the UCL Institute of Ophthalmology, where he joined in 2022. His research focuses on the molecular genetics of inherited ocular disorders with interests in primary congenital glaucoma (PCG), and ectopia lentis. He studies both ectopia lentis in syndromic forms, including Marfan syndrome (FBN1), and isolated forms caused by variants in genes such as ADAMTSL4. A key aim is to understand the genetic basis of ectopia lentis and its relationship to systemic involvement, including aortic aneurysm. His work integrates next-generation sequencing (NGS), bioinformatics, and molecular genetics to identify and interpret disease-causing variants. He has extensive experience in short-read sequencing analysis and is expanding expertise in long-read sequencing. He also applies in-house bioinformatics pipelines for variant discovery and annotation and is interested in induced pluripotent stem cell (iPSC) models of ectopia lentis and aortic aneurysm.

Dr Cécile Méjécase (PhD)
I graduated BSc. in 2013 and MSc. specialty cellular biology and genetics in 2015 at Université de Versailles-Saint Quentin in France, with honor. I analysed whole exome sequencing data to identify disease-causing defects in patients affected with inherited retinal dystrophy, under the supervision of Pr Isabelle Audo and Dr Christina Zeitz at Vision Institute in Paris, and I obtained my PhD in 2019 from Sorbonne-Université (France). After my PhD, I joined the Ocular Genomics and Therapeutics laboratory, directed by Pr Mariya Moosajee at UCL Institute of Ophthalmology and at the Francis Crick Institute, as post-doctoral research fellow to study autosomal dominant and autosomal recessive RDH12-related diseases and CRB1-retinopathies. I model these diseases with retinal organoids, obtained from induced pluripotent stem cells derived from affected patient fibroblasts. Affected pathways will be revealed by RNA sequencing on retinal organoids and will help to understand physiopathological mechanisms associated with these retinal diseases.
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Nicola Cronbach
I studied medicine at Brighton and Sussex Medical School, graduating in 2013, before commencing my training as an Ophthalmologist in the Oxford region. I have a special interest in glaucoma and developmental eye diseases affecting the anterior segment. I am currently undertaking a PhD studying the genetic causes of congenital glaucoma, a condition in which high eye pressure in babies and young children can cause blindness if not recognised or treated promptly. My aim is to identify more of the genes that cause this disease so that more families will be able to access accurate genetic counselling and family planning advice, and to help find new targets for future treatment development.

Nadrique Simms
In 2021, I completed a BSc in Medical Physiology at the University of Leicester. I then worked as a diabetic eye screener before joining the NHS Scientist Training Programme in Ophthalmic and Vision Science at Great Ormond Street Hospital for Children from 2022 to 2025, alongside an MSc in Clinical Science at Aston University. I became an HCPC registered Clinical Scientist in 2025. I am now a Research Assistant in the Moosajee lab, where I am helping to validate child-friendly iPad-based visual function tests for Stargardt disease as potential clinical trial outcome measures.

Mubeen Khan
I am a Research Fellow at the UCL Institute of Ophthalmology, working in the group of Mariya Moosajee, where my research focuses on the molecular mechanisms underlying inherited retinal diseases. I investigate the functional impact of genetic variants using minigene assays, stable cell models, and iPSC-derived retinal organoids. My work centres on splicing defects and their therapeutic rescue using antisense oligonucleotides. By integrating genomics with experimental validation, I aim to bridge variant interpretation with translational strategies, contributing to improved diagnosis and the development of targeted therapies for rare genetic eye disorders.

Claire Castle
Claire is a Research Fellow in Professor Mariya Moosajee’s group at UCL’s Institute of Ophthalmology. She is currently working on the project ‘Exploring children and adult experiences of genetic eye diseases’. Claire is a social scientist with a background in the sight loss and disability sector. She has published work in multiple peer-reviewed journals, covering issues of access and discrimination for people living with sight loss and/or disability in the UK. This includes work relating to employment, health and well-being, social and recreational participation, and engagement with rehabilitation and support services. Claire joined the Institute of Ophthalmology in 2026.

Dr Doğa Gülhan
My current work as a Research Fellow focuses on digital phenotyping and analysis of ophthalmology-related datasets, often in relation to visual impairment, patient-reported outcomes, everyday activity, and eye care. This includes, for example, secondary analysis of UK Biobank data, phone-based tracking data, survey-based studies on choroideremia and patient activation, mouse activity data, and evidence synthesis on smartphone apps for eye health. My background is in psychology and cognitive science, with previous work in behavioural research across real-world, laboratory, virtual reality, and online studies. My doctoral and postdoctoral research involved visual psychophysics, eye tracking, judgement, and decision-making tasks.
 

Dr Richard Harbottle, DKFZ, Heidelberg
Dr Dongshan Yang, University of Michigan, USA
Professor Jörg Huwyler, University of Basel, Switzerland
Dr Michael Howell, The Francis Crick Institute
Professor Caetano Reis e Sousa, The Francis Crick Institute
Dr Joe Rainger, Roslin Institute, Scotland
Professor Andrew Webster, UCL
Dr Anthony Khawaja, UCL
Professor Rui Chen, University of California, Irvine, USA
Professor Michael Gorin, UCSF, USA
Professor Jacque Duncan, UCSF, USA
Professor Kathleen Boesze-Battaglia, University of Pennsylvania, USA
Professor Ian MacDonald, University of Montreal, Canada
Ass. Prof Erwin Van Wijk, Radboud University, Nijmegen, Netherlands
Dr Pratik Gurnani, UCL
Professor Stephen Hart, UCL
Professor Miguel Seabra, Universidade NOVA de Lisboa, Portugal
Dr Helen May Simera, University of Mainz, Germany
Professor Jo Huiqing Zhou, Radboud University, Nijmegen, Netherlands

Dr Dulce de Cunha Lima
Dr Nicholas Owen
Dr Philippa Harding
Dr Jonathan Eintracht

Professor Mariya Moosajee 
Email: m.moosajee@ucl.ac.uk

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We are based at the UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL.