This article is more than 5 years old. Information may no longer be current.
Risk alleles for neovascular AMD may determine neovascularization in pachychoroid patients
Click Here to Manage Email Alerts
MIAMI — The frequency of risk alleles predisposing to neovascularization in age-related macular degeneration also predicts neovascularization in pachychoroid disease, according to a study presented here.
“The risk alleles investigated seem predisposed to the neovascularization, not necessarily just in AMD, but perhaps in other diseases such as pachychoroid,” K. Bailey Freund, MD, said at Angiogenesis, Exudation, and Degeneration 2016.
Freund and colleagues conducted a study to determine whether 12 DNA single nucleotide polymorphisms, known to confer susceptibility to neovascular AMD, might influence the risk for neovascularization in patients with a pachychoroid phenotype.
The prospective case control study included 201 subjects older than 50 years who were categorized into four phenotype groups: neovascular AMD (A), pachychoroid with neovascularization (B), pachychoroid without neovascularization (C) and normal subjects (D).
“DNA was isolated from buccal mucosal swabs, and we looked for 12 single nucleotide polymorphisms and risk allele frequencies per phenotype,” Freund said.
Mean patient age was 82 years for group A, 72 years for group B, 64 years for group C and 69 years for group D.
“Patients without neovascularization with pachychoroid were somewhat younger, which may have strengthened our results because for all we know later in life these patients would have gone on to get neovascularization,” he said.
Mean choroidal thickness was 144 µm in group A, 352 µm in group B, 361 µm in group C and 169 µm in group D.
For the 12 DNA single nucleotide polymorphisms studied, Freund and colleagues found that group A had a higher allele frequency than groups C and D, group B had a higher allele frequency than group C, and group A had an equivalent allele frequency to group B in most DNA single nucleotide polymorphisms.
Pachychoroid patients differentiate into neovascular or non-neovascular phenotypes determined by risk allele; however, phenotypic differences in neovascular characteristics between AMD and pachychoroid remain unexplained, according to Freund.
“The strength in our results was that our study was prospective, and I think we were able to see these differences because we carefully chose our phenotypes,” Freund said. – by Kristie L. Kahl and Nhu Te
Disclosure: Freund reports he has financial interest with Vitreous Retina Macula Consultants of New York, the LuEsther T. Mertz Retinal Research Center at Manhattan Eye, Ear and Throat Hospital and New York University Medical School.