Drusen is likely a genetic marker for AMD, study finds. Photo: Getty, Anna Bedwell, OD. Click image to enlarge.

Findings from a recent study suggest a link between the genetic risk of age-related macular degeneration (AMD) and drusen. Additional research will allow for a better picture of this connection as well as an improved understanding of the biological risk factors of drusen development, according to the research team.

The researchers recruited participants from Amish communities in Ohio, Indiana and Pennsylvania who then underwent a basic health history, ophthalmologic examination and genotyping. Genome-wide association analysis (GWAS) was used to identify the presence and quantity of three retinal traits: geographic atrophy, drusen area and drusen volume.

Findings from this analysis were compared with a prior GWAS that included predominantly individuals of European ancestry. The study authors used a genetic risk score for AMD to predict the presence and quantity of the retinal traits.

The analyses included 1,074 participants. The researchers reported that six single nucleotide polymorphisms (SNPs) met criteria for genome-wide significance, and 48 were suggestively associated across three retinal traits. The data revealed that the significant SNPs were not highly correlated with known risk SNPs for AMD. Additionally, a genetic risk score for AMD offered significant predictive value of the retinal traits, the study authors noted.

“We conclude that there is an underlying genetic component to drusen development that may be somewhat separated from the biological pathways considered in AMD development. With the relatively high heritability of AMD for a complex disease, it is not surprising that drusen may also be inherited in a similar manner,” the researchers wrote in their paper published in Investigative Ophthalmology & Visual Science. “Work on the genetic risk of drusen could aid in improving understanding of drusen as a biomarker for genetic risk of AMD. Building this knowledge could serve to improve screening and treatment to prevent AMD by more thorough incorporation of drusen burden into such practices.”