At Blaine Bettinger's Genetic Genealogist blog, he points out a recent study that traced a mutation in the adenomatous polyposis coli gene to Mr. and Mrs. George Fry, an English couple who came to the New World early in the 17th century. The mutation, which increases a carrier's chances of developing colon cancer, was traced through the Fry family tree and also through genotyping. Studies tracing SNPs to single ancestors will become more common as sequencing becomes less costly, Bettinger believes. "When people begin to combine genetic sequencing with family trees, these studies will be limited only by the availability of family trees and computing power (I imagine that some of it will be quite complex)," he writes.