A founder mutation in presenilin 1 causing early-onset Alzheimer disease in unrelated Caribbean Hispanic families

A mutation in the presenilin 1 gene was found in eight out of 19 Caribbean Hispanic families with a family history of Alzheimer's disease that occurred before the age of 55. The families were not related to each other, indicating that they all had a common ancestor. The rate of Alzheimer's disease is higher in Caribbean Hispanics than in non-Hispanic whites.