McGarvey, who is also director of the International Health Institute at Brown University, has studied the Samoan people since 1976. He said this new effort builds on earlier research that has looked at Samoans as they have become more urbanized and their physical activity and diets have changed. Those earlier efforts did find some variation on a small scale, but McGarvey said wide-scale genotyping should identify the variation definitively, if it exists.

Researchers will aim for a nuanced evaluation. They will determine whether susceptibility genes are present and whether they produce levels of obesity and diabetes only when subjects eat more but don't exercise enough to burn excess calories.

"You want to see if the Samoans have a genetic propensity to have high instances of (diabetes or obesity) or if it is kept in check by better diet and exercise," McGarvey said.

Researchers will incorporate a wide variety of study subjects. More than three-quarters of Samoan men are still engaged in traditional farming and fishing, for example. Researchers will try to contrast these subjects with Samoans who are living in town, working in offices, factories and shops, and may drive more and walk less.

McGarvey and his researchers will collect blood samples, study diets, measure height and weight, and take blood pressure. They will also ask about nutrition, physical activity, doctor visits, and use of medicines. Finally, researchers will evaluate demographic information such as education, employment and income, as that data can have a direct relationship to certain health behaviors.

Source: Brown University