A collaboration between researchers at the Queen Mary University of London, the University of Manchester, Cardiff University, and Radboud University Medical Center, Nijmegen, led to a salutary discovery: the guilty party in age-related macular degeneration (AMD). It looks like a protein is responsible for the disease that blinds every other fourth victim of blindness. It is called H-related protein 4 (FHR-4), and it can be spotted with blood tests.
What is macular degeneration?
It is a degenerative medical condition that may result in blurred or no vision in the center of the visual field. It can happen in both eyes, or just in one. It is asymptomatic. Only when the disease settles, some people experience a gradual worsening of vision. It doesn’t lead to complete blindness, but the further deterioration of vision gets pretty close.
The eye’s macula is the one usually affected by AMD. The patient loses the central vision, and that makes it hard to recognize faces, drive, read, or perform other activities of daily life. One can also experience visual hallucinations. It is the fourth cause of blindness after cataracts, preterm birth, and glaucoma.
H-related protein 4
Until now, it was speculated that AMD is a genetic disorder. The discovery of H-related protein involvement in the disease confirms it. Elevated levels of the protein in patients’ blood were found consistent with the genetic markers that coded for the H family of proteins. The high level of FHR-4 in the blood leads to a high level of the same protein in the eye’s macula, thus causing and making macular degeneration evolve.
“FHR4 is a critical controller of that part of the immune system which affects the eyes. We have shown that genetically determined higher blood FHR4 levels leads to more FHR4 in the eye which in turn increases the risk of the uncontrolled immune system response that drives the disease,” said Professor Paul Bishop from the University of, one of the study leaders
This finding can lead to the early discovery of the disease within patients by simply measuring blood levels of FHR4. It could also become the reason for new research in finding the cure.