Dr Mervyn Thomas

Clinical Associate Professor, Honorary Consultant Ophthalmologist and Clinical Lead (Ulverscroft Eye Unit)

Mervyn Thomas profile

School/Department: Psychology and Vision Sciences, School of

Telephone: +44 (0)116 252 5879



I am a Clinical Associate Professor, Honorary Consultant Ophthalmologist and Clinical lead of the Ulverscroft Eye Unit at the University of Leicester.

I received my medical degree in 2013 and completed both an iBSc and PhD during medical school. I received the Wolfson prize (Royal College of Physicians), Alcon research prize during my intercalating research years and the PhD prize for the best thesis across the College of Life Sciences. I have progressed successfully through the competitive integrated clinical academic training pathway initially as an NIHR Academic Clinical Fellow and subsequently an NIHR Clinical Lecturer. Through the NIHR Integrated Academic Training (IAT) programme, I have received continuous funding during the course of my clinical training.

Currently I lead a translational programme of research ranging from lab-based genetic and animal model work to patient-based deep phenotyping multi-centre studies. I supervise academic doctors, orthoptists, post-graduate and undergraduate students. My work has gained national and international recognition evidenced by the multiple awards and seminal publications. My work on foveal hypoplasia and developing a grading system is universally accepted and utilised daily in clinics around the world. I was elected to the ARVO program committee and currently chair the EY section. I am also a scientific advisor for Nystagmus Network and on the Global Albinism Alliance Scientific Committee.


I have a clinical and research focus on developmental ocular disorders ocular imaging and genetics. This includes application of different imaging modalities and genetic techniques to improve the diagnosis and predict prognosis in paediatric and neuro-ophthalmology more recently with the use of artificial intelligence. My work has been supported by grants from Medical Research Council, Wellcome Trust, Academy of Medical Sciences, Health Education England, Ulverscroft Foundation and Fight for Sight.


Aamir A, Thomas MG. Discordant phenotypes in twins with infantile nystagmus. Sci Rep. 2021 Feb 2;11(1):2826. 

Thomas MG, et al. Optic Nerve Head and Retinal Abnormalities Associated with Congenital Fibrosis of the Extraocular Muscles. Int. J. Mol. Sci. 2021, 22, 2575

Thomas MG, et al. Normal and abnormal foveal development. Br J Ophthalmol. 2020 Nov 4: bjophthalmol-2020-316348. 

Liu S, Thomas MG. Current and emerging treatments for albinism. Surv Ophthalmol. 2021 Mar-Apr;66(2):362-377. 

Kuht HJ, Thomas MG. SLC38A8 mutations result in arrested retinal development with loss of cone photoreceptor specialization. Hum Mol Genet. 2020 Nov 4;29(18):2989-3002. 

Rufai SR, Thomas MG, et al. Can Structural Grading of Foveal Hypoplasia Predict Future Vision in Infantile Nystagmus?: A Longitudinal Study. Ophthalmology. 2020 Apr;127(4):492-500. 

Thomas MG, et al. Congenital monocular elevation deficiency associated with a novel TUBB3 gene variant. Br J Ophthalmol. 2020 Apr;104(4):547-550. 

Mayer AK*, Mahajnah M*, Thomas MG*, et al. Homozygous stop mutation in AHR causes autosomal recessive foveal hypoplasia and infantile nystagmus. Brain. 2019 Jun 1;142(6):1528-1534. (*first co-author) 

Thomas MG, et al. Development and clinical utility of a novel diagnostic nystagmus gene panel using targeted next-generation sequencing. Eur J Hum Genet. 2017 Jun;25(6):725-734. 

Thomas MG, et al. Abnormal retinal development associated with FRMD7 mutations. Hum Mol Genet. 2014 Aug 1;23(15):4086-93. 

Thomas S*, Thomas MG*, et al. Autosomal-dominant nystagmus, foveal hypoplasia and presenile cataract associated with a novel PAX6 mutation. Eur J Hum Genet. 2014 Mar;22(3):344-9. (*first co-author)

Watkins RJ, Patil R, Goult BT, Thomas MG, Gottlob I, Shackleton S. A novel interaction between FRMD7 and CASK: evidence for a causal role in idiopathic infantile nystagmus. Hum Mol Genet. 2013 May 15;22(10):2105-18. 

Thomas MG, et al. Early signs of longitudinal progressive cone photoreceptor degeneration in achromatopsia. Br J Ophthalmol. 2012 Sep;96(9):1232-6. 

Thomas MG, et al. Structural grading of foveal hypoplasia using spectral-domain optical coherence tomography a predictor of visual acuity? Ophthalmology. 2011 Aug;118(8):1653-60. 

Thomas MG, et al. The clinical and molecular genetic features of idiopathic infantile periodic alternating nystagmus. Brain. 2011 Mar;134(Pt 3):892-902. 

Thomas MG, et al. High-resolution in vivo imaging in achromatopsia. Ophthalmology. 2011 May;118(5):882-7.


PhD students:

1. Helen Kuht (primary supervisor) - "Insights into foveal developmental disorders using deep phenotyping techniques and artificial intelligence"

Prizes: Highly Commended PhD student of the year award (national postgrad awards), ARVO international travel grant, BCOVS best presentation prize, BIPOSA best abstract and presentation prize

Destination: Wellcome Trust Post-doctoral Fellowship (Ulverscroft Eye Unit, Supervisor: Dr Mervyn Thomas), subsequently appointed to work at the Office of the National Data Guardian.  

2. Sohaib Rufai (co-supervisor) - "Early Recognition of Raised Intracranial Pressure in Craniosynostosis using Handheld OCT"

Prizes: NIHR Doctoral Research Fellowship, BIPOSA best presentation prize, ARVO MIT poster prize, College of Life Sciences PhD Prize

Destination: NIHR Clinical Lecturer (Ulverscroft Eye Unit, Research Supervisor: Dr Mervyn Thomas, Academic Supervisor: Professor Julian Barwell)

3. Ravi Purohit (co-supervisor) - "Development of the optic nerve head and foveation strategies in infants and young children with infantile nystagmus" Prizes: ARVO international travel grant, Topol Digital Fellowship

Destination: Oxford University Hospitals (Lead of ROP and craniofacial service)

Intercalated Medical Students:

1. Susmit Das

2. Vanessa Rodwell

3. Rishi Sekhri

4. George Garratt

5. Annabel Birchall

6. Gurtek Samra

7. Vincent Dwianta

8. Fatimah Riaz


I regularly teach undergraduate students, postgraduate students and trainee doctors at various stages of their training. I have been involved in supporting peer-led teaching through the Leicester SCRUBS (surgical society). I contribute to the advanced care practitioner (ACP) course at the University of Sheffield (modules: ocular genetics and ocular imaging). My commitment to teaching and supervision is reflected in my receipt of the Associate Fellow of the Higher Education Academy (AFHEA) award, a teaching partnership award, and my nomination as a finalist for the PhD Supervisor of the Year in the National Postgrad Awards 

Press and media

I have expertise in the following areas: retinal development (normal and abnormal foveal and optic nerve development); ocular imaging; nystagmus; inherited retinal diseases; optic nerve diseases (papilloedema/pseudopapilloedema); animal models of ocular disorders.



-General Medical Council (GMC)

-Royal College of Ophthalmology (RCOphth)

-European Paediatric Ophthalmology Society (EPOS)

-British & Irish Paediatric Ophthalmology and Strabismus Association (BIPOSA)

-European Retina Macula and Vitreous Society (EURETINA)

-Medical Defence Union (MDU)

-Nystagmus Network (Patient charity - Scientific Advisor)

-Nystagmus UK Eye research group (NUKE)

-Global Albinism Alliance Scientific Committee

-Foveal Development Investigators Group (FDIG - lead)

-Genomics England Clinical Interpretation Partnership (GeCIP - Hearing and Sight Domain)

-Association for Research in Vision and Ophthalmology (ARVO - Chair (EY))

-UK Biobank Eye and Vision Consortium Member

-ClinGen Variant Curation Expert Panel (VCEP) for albinism


Awards/Invited lectures:

2023: Keynote talk at the Academy of Medical Sciences INSPIRE medical student meeting: Title: “From Student to Clinician Scientist: Start Small, Dream Big”

2022: Ulverscroft David Owen prize (Royal College of Ophthalmologists)

2022: Keynote talk Nederlands Oogheelkundig Gezelschap (NOG). This is the equivalent of the Royal College Meeting in Netherlands. Talk: “Insights into normal and abnormal foveal development: from genes to phenotype”

2021: National Postgrad Awards best supervisor finalist (1 of 3)

2021: European Retina Macula and Vitreous Society (EURETINA): Symposium title: "Foveal development in health and in disease. Insights from histology OCT OCT-A and Adaptive Optics"

2021: German Ophthalmological Society (Deutsche Ophthalmologische Gesellschaft): “Normal foveal development”

2021: Association for Research in Vision and Ophthalmology (ARVO): “Into the future: Designing clinical gene panels for strabismus based on the nystagmus model”

2021: Sheffield School of Orthoptics: “Normal and Abnormal Retinal Development: Insights from Embryology to Pathology”

2021: World Society of Paediatric Ophthalmology and Strabismus (WSPOS): “Use of Ophthalmic Imaging in the Diagnosis and Classification of Infantile Nystagmus Syndrome”

2020: Midlands Ophthalmic Society Prize

2020: ARVO (invited talk at Mini-symposium on genetics of strabismus)

2017: European Paediatric Ophthalmology Society Prize

2017: Research Excellence Framework (REF)-Research impact award

2012: College of Life Sciences PhD prize for best PhD Thesis

2011: Vernon Prize

2010: David Meyer Prize

2008: Alcon Research Prize

2008: Wolfson Award (Royal College of Physicians)


09/2004 - 07/2013: University of Leicester: Bachelor of Medicine and Surgery MBChB (Merit and Teaching partnership award)

09/2007 - 07/2008: University of Leicester: Bachelor of Science (Intercalated) BSc (Honours) Awarded Wolfson prize and Alcon Research prize

08/2008 - 07/2012: University of Leicester: PhD (Ophthalmology and Genetics) (PhD prize for the best thesis in College of Life Sciences)

01/2019: Royal Society of Biology: Personal animal license (Zebrafish) Ethics and Legislation (E1+L) PIL A PILB

08/2019: Higher Education Academy: Teaching: Associate Fellow of the Higher Education Academy (AFHEA)

12/2019: Royal Veterinary College: Project License: E2 and PPL certificate

01/2022: Fellow of the Royal College of Ophthalmologists (FRCOphth)

08/2022: Certificate of Completion of Training (CCT)

11/2022: Five-year project license awarded by Home Office for Zebrafish research

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