Researchers who made a knock-in mouse-model of the genetic disorder retinitis pigmentosa 59, or RP59, expected to see retinal degeneration and retinal thinning. As reported in the journal Cells, they surprisingly found none, calling into question the commonly accepted — though never proved — mechanism for RP59.
“While in principle it would be reasonable to consider RP59 as a congenital disorder of glycosylation, due to the associated mutation in DHDDS, an enzyme required for glycosylation, there is no direct evidence to demonstrate a glycosylation defect in the human retinal disease or in any animal model of RP59 generated to date,” said Steven Pittler, Ph.D., professor and director of the University of Alabama at Birmingham School of Optometry and Vision Science Research Center.