A study reported highly positive response of participants to predictive genetic testing for AMD. All subjects showed high interest in receiving the information, and many felt encouraged to adopt or maintain healthy habits for disease prevention.
One hundred subjects between 50 and 65 years old with at least one family member with age-related macular degeneration. DNA samples were genotyped for five single-nucleotide polymorphisms in the CFH gene and one single-nucleotide polymorphism in the ARMS-2 gene, the C3 gene and the mitochondrial ND2 gene. A risk score was calculated using a model based on odds ratios, lifetime risk of advanced AMD and known population prevalence of genotype, haplotype, and smoking risk.
After the results, an optometrist provided counseling for protective behaviors. Subjects were interviewed 1 to 3 months later regarding their motivation and experience with the study, test results and behavior changes as a consequence of genetic testing.
All participants commented favorably on the study and the information provided and were happy to have received information on prevention measures. They had a low risk score for developing AMD within 10 years, but many of them said they had made lifestyle changes after receiving the study results.
Twenty-seven people reported specific changes, such as taking vitamin supplements and wearing sunglasses and a brimmed hat when outdoors. Sixteen people said that the study confirmed the value of habits they already had, such as not smoking wearing glasses and taking vitamin supplements.
The relatively small geographic area, the 99% prevalence of white ethnicity and the high level of education of participants was a limitation in this study, which may not be “representative of the more diverse United States in terms of race/ethnicity and education level,” the authors wrote. However, the study results suggest that there are reasons to consider genetic testing.
“I think that one reason to consider predictive genetic testing that could be supported by our data is the response by people to change health behaviors,” author Catherine A. McCarty, PhD, MPH, told Primary Care Optometry News. “In particular, if genetic testing could be the trigger for people to quit smoking, not only their risk of AMD would decline, but also their risk to develop many other conditions including heart disease, lung cancer and chronic obstructive pulmonary disease. That is very powerful.” – by Michela Cimberle
Disclosure: The authors reported no relevant financial disclosures.