The Amish offered a rare opportunity for Dr. Judith Westman and her team.
The members of Holmes County's Amish population all descend from 100 original settlers to the area about 200 years ago. Because they remain relatively sequestered and marry within the community, their family trees are heavily intertwined.
That makes for an interesting gene pool.
Researchers already know that certain types of rare genetic disorders are more common among the Amish, and they are interested in looking for information about more common medical conditions, including cancer.
Westman, director of human genetics at Ohio State University's Comprehensive Cancer Center, fully expected to find some genetic links to cancer within the 92 families she studied.
But in a paper recently published in the journal Cancer Causes & Control, she and her fellow researchers reveal that they found no such markers and instead are left wondering whether the Amish have genetic differences that protect them from cancer.
The study looked at cancer incidence reported by 92 families in Holmes County. The researchers relied on reports from the families and from a state database of known cancer cases. They then compared incidence in that population with incidence among all white Ohioans.
Rates are based on the average number of people per 100,000 who developed the disease each year between 1996 and 2003.
The overall rate of cancer in Amish adults was 390, compared with 647 in the population at large.
The low rates of tobacco use among the Amish explained some of that, but not all. Rates of tobacco-related cancers were 82 for the Amish and 222 for others.
But rates of cancers not linked to smoking or other tobacco use also were lower: 308 compared with 425.
Westman has no explanation but suspects a combination of factors could be at play.
The Amish lifestyle is different, for one. They eat a lot of food that they grow or raise and rarely consume processed foods. They tend to get more physical activity, and even though they sometimes are overweight, obesity is rare, she said.
Andy Yoder, a second-year Ohio State medical student who grew up in an Amish home in Sugarcreek, said he wonders about the role of stress.
"They all have their families and friends close by, which is helpful."
Another difference worth exploring is that Amish people live in rural areas and have less exposure to pollutants than people who live in cities, Yoder said.
Then there are the genetic mysteries that might contribute to lower cancer incidence. That's something Westman and others would love to know more about, but "that is a statistical genetic nightmare."
"Scientifically, it's a whole lot easier to check for something that's there," she said. "It's like trying to find a black hole to check for something that's protective rather than causative."
Holmes County Health Commissioner Dr. D.J. McFadden said he welcomes research that uncovers medical information about the Amish and that might help unravel mysteries about diseases that affect everyone.
"We're constantly looking for ways to improve the health of the nation, and if you have some things that you can identify in communities with low incidences of cancer, it makes sense to follow some of those practices," he said.
"We have what we call the Mediterranean diet; maybe somewhere down the road people might talk about the Amish or the Anabaptist lifestyle."