Blindness study shows how gene causes middle-age sight loss

Chemical changes in the eye that can lead to blindness have been identified by scientists: September 2017

derived-organoid-optic- — When you float stem cell colonies off their dish, allow them to form 'embryoid bodes' and pattern them towards an eye field state, an outpouching from the embryoid body occurs.

Chemical changes in the eye that can lead to blindness have been identified by a Medical Research Council Human Genetics Unit team led by Dr Roly Megaw.

These findings aid the understanding of a genetic condition that causes sight loss for one in 3,000 people in the UK. They were presented at the Eye Development and Degeneration 2017 conference hosted within the MRC Institute for Genetics and Molecular Medicine yesterday.

This research team examined how changes in a gene known as RPGR damage eye cells to cause a disorder known as X-linked retinitis pigmentosa. The condition is incurable and affects night and peripheral vision before gradually causing blindness in middle age.

They took skin samples from two patients and transformed stem cells, which can change into any cell type, into light-sensing eye cells known as photoreceptors. They compared these with cells from healthy relatives of the patients. Photoreceptors decay in retinitis pigmentosa patients and the researches found that the fundamental structure of the patient’s photoreceptors differed when compared with those from their family members.

Follow-up studies in mice identified key molecules that interact with the RPGR gene to maintain the structure of photoreceptors. When the RPGR gene is flawed, the photoreceptor structure is compromised and cannot function correctly, leading to sight loss.

Dr Roly Megaw, ECAT Clinical Lecturer with the University of Edinburgh’s MRC Human Genetics Unit, who led the study, said: “By furthering our understanding of the RPGR gene and its effects on photoreceptor cells, we hope our findings bring us closer to developing a possible treatment for this devastating disease.”

The study is published in the journal Nature Communications and was carried out at the University of Edinburgh’s Medical Research Council Centre for Regenerative Medicine. It was funded by the Wellcome Trust and the charity Retinitis Pigmentosa Fighting Blindness.

Links

Pleasantine Mill Research Group: http://www.ed.ac.uk/mrc-human-genetics-unit/research/mill-group

Charity Retinitis Pigmentosa Fighting Blindness. http://www.ed.ac.uk/news/2017/gene-study-sheds-light-on-middle-age-sight-loss

University of Edinburgh Press Release https://www.rpfightingblindness.org.uk/home.php?home=yes

This article was published on 8 Sep, 2017