Office of Technology Development (OTD)

Jay Neitz, Ph.D.
Medical College of Wisconsin
Professor, Ophthalmology Research

Maureen Neitz, Ph.D.
Medical College of Wisconsin
Professor, Ophthalmology Research

People over the age of 75 years have a one in three chance of developing age-related macular degeneration (AMD), and one in ten people over the age of 80 experience severe vision loss from late stages of the disease. Severe vision loss is associated with late stage AMD (stage 4) and thus slowing or halting disease progression in early stages would have tremendous economic and quality of life benefits. Recent studies have demonstrated that a non-synonymous C versus T nucleotide polymorphism in the gene for complement factor H (CFH), substituting histidine for tyrosine at position 402 (Y402H), is a significant risk factor for developing AMD. After activation of the immune system, CFH normally regulates complement by inhibiting death of host cells targeted by the immune system for destruction. A role for CFH and the immune system in AMD is further supported by previous observations that CFH and other components of the complement pathway are found in drusen, the extracellular deposits that are key biomarkers for AMD. Despite the importance of CFH in AMD, the presence or absence of the CFH Y402H risk allele has limited predictive power—about 60% of the population is either homozygous or heterozygous for the CFH Y402H risk allele, yet 56% of people 95 years or older have a CFH risk allele but do not have late stage AMD.

The cone opsin genes are perhaps the most highly mutated in the human genome and research at the Medical College of Wisconsin has revealed that mutant cone opsin genes play a large part in
determining which individuals with a CFH Y402H risk allele will ultimately lose vision. In this invention, alleles of OPN1LW are shown to be associated with age related macular degeneration (AMD). OPN1LW expression is retina-specific and principally confined to the macula where it generates precursors of toxic compounds found in retinal deposits (i.e. drusen) that are biomarkers for AMD. This is consistent with a two-hit genetic mechanism for AMD in which OPN1LW is responsible for disease initiation and inflammatogenic risk factors such as complement factor H (CFH) are responsible for disease progression. In the present study of 464 individuals, 72% of individuals with late AMD were genotyped to have both CFH Y402H and OPN1LW risk alleles while only 39% of individuals with stage 1 have both risks. This indicates that among patients diagnosed with the early signs of AMD the CFH OPN1LW combination is a huge factor in determining who will ultimately lose vision.

Conventional wisdom holds that common diseases, such as AMD, are complex, being polygenic with multiple genes interacting together with environmental factors to cause disease. However, AMD is in fact simpler than anyone imagined with only two interacting genes responsible for the majority of the disease, both in terms of the number of people who have these two genetic risk factors and get the disease, and in terms of the degree to which the combination of these two risk factors increase the probability of getting the disease.

Identifies AMD patients at risk for
vision loss

Identifies patients at risk to get AMD

Compatible with any SNP analysis platform

Simple two-gene target
 

Clinical Data