Clinician-scientist strategizes different genetic approaches to early-onset, late-onset glaucoma
WASHINGTON — In the clinician-scientist lecture at the American Glaucoma Society meeting here, Janey L. Wiggs, MD, PhD, delineated two different approaches to using genetics in glaucoma research, depending on whether the disease occurs early or late.
“If you can find genes that cause glaucoma and understand what the protein products of those genes do, you can define the molecular events that are responsible for the disease,” Wiggs said.
That is the first step in developing treatment targeted at the molecular events responsible for the disease, ideally treatments that could be curative, she said. Furthermore, identifying and understanding genes that cause glaucoma also help develop diagnostic and screening tools that can identify persons at risk for glaucoma before irreversible damage to the optic nerve develops, allowing for early prevention and again, ideally, curative therapies.
Janey L. Wiggs
For early-onset diseases, those occurring before 40 years of age, that are inherited as autosomal dominant or autosomal recessive traits, mutations have a large biological effect and are causative, Wiggs said. Late-onset diseases have complex inheritance, meaning multiple genes, gene-gene interactions, environmental factors and gene pathways contribute to the disease, she said.
“Genetic testing for early-onset glaucoma is useful,” Wiggs said, because it can confirm a diagnosis, target treatment and surveillance, inform genetic counseling and facilitate gene-based therapies once they are available.
For adult-onset glaucoma, Wiggs said, “We’re hopeful that comprehensive and useful gene score panels will be available as more and more genes that contribute to primary open angle-glaucoma are discovered.”
Genes, both causative for early-onset and influential for late-onset, have been identified, but more are needed, Wiggs said. Data are being pooled from various gene data repositories into the NEIGHBORHOOD consortium, where data on approximately 4,000 glaucoma cases and nearly 35,000 control subjects are amassed so far, she said. This resource will help identify more glaucoma-related genes.
“We’re excited about the next steps for the consortium, which include meta-analysis on this much larger data set, which we think is quite likely to identify additional genes that will be important for understanding primary open-angle glaucoma,” Wiggs said.
Disclosure: Wiggs receives research funding from the National Institutes of Health and March of Dimes.