Genetic testing can be a very beneficial technology; it can diagnose unusual or rare disorders, and can improve the treatment of certain diseases, including cancer. But the cost of this testing can be a barrier, and many people are not able to access genetic screening even when it can dramatically improve outcomes. Scientists at Oregon Health & Science University wanted to try to eliminate that barrier by providing free genetic screening to any adult Oregon resident with a family history of inherited cancer and familial hypercholesteremia. In this effort, more than 13,000 Oregon residents have been screened since 2018, and the findings have been reported in The American Journal of Human Genetics.
"We're hoping that this can really be used as a model for other states that want to do low-cost population screening," said first study author Timothy O'Brien, a staff scientist at Knight Diagnostic Laboratories. "We've provided a kind of roadmap where up-and-coming screening programs can look at us and see both what worked and what could be improved upon."
Participants were recruited through social media campaigns and in-person outreach at events such as farmers' markets. Only a mouthwash saliva sample was required from participants, and people were also able to use vending machines or the mail to obtain and return testing kits. After consenting on a HIPAA-compliant app, variants in 31 inherited cancer linked genes and one familial hypercholesteremia gene were assessed in the participants' DNA.
The researchers wanted to focus on obtaining answers that people could use, and variants that provided people with actionable data, so there are options for responding to the findings, noted senior study author Sue Richards, a Professor Emeritus at Oregon Health & Science University. "It could be something like changing your screening habits, taking a prophylactic surgery or medication, or consulting with your clinician."
This study revealed that of the 13,000 participants, 710 carried variants that can cause disease. Genetic counselors contacted all participants who carried these variants, so they would be informed about what risk they might face, and how to manage the results.
Genetic counseling is a crucial part of this study. The reports that are created from patient data are technical, and can be difficult for a layperson to understand; people who carry variants that are associated with disease may not necessarily develop that disorder, for example. "The counselor also talks to them not only about their own health and family history but also how they pass that information along to other family members, since they are at risk of having the variant as well," Richards noted.
About five percent of study participants carried a cancer-linked variant. This is a higher proportion than what is seen in the general population, and could happen because more people who have family members with cancer seek genetic screening compared to the average individual. It may also be related to the genes that were screened in this study.
The researchers noted that this work has shown that the range of genes that are analyzed in a study can dramatically influence how many participants get positive results. They would like to expand this program in the future, and potentially benefit more people.
"The overall goal of this project was really to help Oregonians and empower them with this health information," O'Brien said. "We feel like we've been able to accomplish that and hope that this continues to be a strong proponent of health for Oregonians in the future."
Sources: Cell Press, American Journal of Human Genetics