In January I wrote about a study that traced a mutation in a single colon cancer gene to 1630. Today, researchers announced that a founder mutation in another gene, MSH2, has been traced to roughly 500 years ago (“Origins and Prevalence of the American Founder Mutation of MSH2” (pdf)).
MSH2 is a mismatch repair gene, and mutations in the gene results in Lynch syndrome, also known as hereditary nonpolypsis colorectal cancer. Lynch syndrome accounts for 2.8% of all colon cancers in the Western world, with 4,500 cases a year in the U.S. One specific mutation in MSH2, the deletion of exons 1 through 6, was named the American Founder Mutation (AFM) and was identified in nine families. Previously, research had suggested that the mutation in the MSH2 gene had been brought to Pennsylvania by German immigrants in the early 1700’s.