Some people inherit genetic changes that put them at higher risk of developing certain cancers or heart disease. A simple genetic test can identify those risks early, creating opportunities to prevent disease or detect it sooner – but only if it reaches the people who could benefit.
A new study from the Medical University of South Carolina (MUSC) suggests that it is possible to reach people through populationwide genomic screening programs. Researchers found that more than 50,000 adults have completed screening through MUSC's In Our DNA SC , a community health research project that has reached participants in all 46 South Carolina counties, including many rural and socially vulnerable communities.
Published in JAMA Network Open, the findings show that combining flexible testing options, community partnerships and implementation science can bring populationwide genomic screening to communities that have historically faced barriers to this type of care.
"Our goal was to understand the reach of the program," said Kalyani Sonawane, Ph.D. , assistant director of data science and analytics at MUSC Hollings Cancer Center . "South Carolina is a rural state with many medically underserved communities. We wanted to know whether we were truly reaching people across the state, not just those who live near large medical centers."
For Daniel Judge, M.D. , principal investigator of In Our DNA SC and director of the MUSC Cardiovascular Genetics Program, reaching those communities is only the first step.
"Genomic screening gives us the opportunity to identify people with inherited risk before they become sick," Judge said. "If we can find those individuals early, we can connect them with genetic counseling, screening and preventive care that should ultimately save lives."
Looking beyond the clinic
In Our DNA SC is a voluntary research program that offers no-cost genetic screening to identify inherited risks for certain diseases. Unlike traditional genetic testing, which is typically used to investigate an existing diagnosis or a known family history, populationwide screening aims to inform people of their risks before symptoms appear.
"We're trying to find people with inherited risks while there's still an opportunity to prevent disease or detect it much earlier," Judge said.
The program screens participants for genetic variants associated with three conditions:
- Hereditary breast and ovarian cancer syndrome.
- Lynch syndrome.
- Familial hypercholesterolemia.
These conditions substantially increase a person's lifetime risk of certain cancers or cardiovascular disease. They were selected because they are actionable and preventable and effective strategies already exist to reduce those risks.
"If we identify someone with an inherited risk for breast cancer, we can begin mammograms earlier," Judge said. "If someone has Lynch syndrome, we can start colonoscopy screenings earlier or more frequently to identify and remove polyps before they become cancerous. And if someone is at risk for high cholesterol, starting medication early can prevent heart disease."
About one in every 65 participants screened has been identified with a variant associated with one of the three conditions. Those participants are offered no-cost genetic counseling appointments to understand what these variants might mean for themselves and their families and to recommend appropriate follow-up care. At the same time, their deidentified information contributes to a secure database that helps researchers to develop more personalized approaches to disease prevention and treatment.
Connecting South Carolinians to screening
The program offers multiple ways for people to participate. They can provide a genetic sample through MUSC clinics, attend community collection events or receive an at-home collection kit. The program also partners with community organizations throughout the state to build awareness and trust.
The process is simple; after consent, participants need only provide either a blood sample or a cheek swab. Because the test includes a noninvasive option and can be completed from home, it removes another barrier that often limits participation.
"The approach wasn't just to offer screening in clinics," Sonawane said. "Because South Carolina has so many rural areas, we knew we needed to go into communities. That population-centered approach was really central to the program's success."
That approach has paid off.
In addition to participants having completed screenings in every South Carolina county, researchers found that after adjusting for population size, participation remained strong across both urban and rural communities.
Judge said that reaching every county was important not only to expand access to genetic screening but also to ensure that South Carolinians are represented in genomic research. The accomplishment is particularly notable because populationwide genomic screening remains relatively uncommon in the U.S.
"For many years, DNA databases used to understand what's considered 'normal' were built largely from populations in places like Iceland, the United Kingdom and parts of the northeastern and western U.S.," he said. "We want to make sure people from every part of South Carolina are represented so future discoveries reflect the diversity of our state."
The research team also looked beyond county populations alone. They compared participation using measures of rurality and the Center for Disease Control and Prevention's Social Vulnerability Index, which incorporates factors such as income, housing, transportation and access to healthcare.
"The big message is that we've done a great job reaching every county regardless of rurality or vulnerability," Sonawane added. "But there's still room for us to improve our reach in some of the most rural counties."
Building trust through community partnerships
Sonawane said the study also underscores the importance of trusted community relationships when introducing new health technologies. Many people have never heard of genomic screening while others might feel anxious learning about potential inherited risk. Community partnerships help to overcome those concerns.
"You can't just introduce a genetic screening program and expect people to participate," she said. "Building trust through community partnerships and ongoing education is key to making this program successful."
While this study focused on whether the program reached diverse populations in South Carolina, the next phase will examine whether that reach translates into better health.
"The next step is understanding the long-term effectiveness," Sonawane said. "Are we helping people get the preventive care they need? That's what we'll be studying over the next several years."
Judge said the program's ultimate goal is to prevent disease before it starts.
"We hope and expect this program will lower the incidence of South Carolina's two leading causes of death: cancer and heart disease," he said. "When people learn about their inherited risks early, they have the opportunity to take steps that can prevent disease or catch it at a much earlier, more treatable stage."
