Researchers from the National Eye Institute (NEI) have identified a novel genetic macular dystrophy, which is yet to be named.
“Affected individuals had scotomas and changes in their maculas indicative of disease, but, for now, they have preserved central vision and no choroidal neovascularisation, unlike in typical Sorsby fundus dystrophy,” said principal investigator Dr Cathy Cukras.
Known macular dystrophies are caused by a handful of genes, with Sorsby fundus dystrophy attributed to TIMP3. This gene encodes a protein that helps regulate retinal blood flow and is secreted from the retinal pigment epithelium (RPE). Prior to this research, all reported TIMP3 gene mutations have been in the mature protein after it had been cleaved from RPE cells. However, these TIMP3 variants prevent cleavage, causing the protein to be stuck in the cell, likely leading to RPE toxicity, said the study’s lead author Dr Bin Guan.