Researchers have traced the origin of a rare version of early-onset Alzheimer's disease in a number of families to a common ancestor who lived in Jalisco, Mexico, NPR's Shots blog reports.
Some 50 families in the US and Mexico are known to have this 431E mutation in presenilin 1 — called the Jalisco mutation as the affected families can all trace their roots to that Mexican state — and, NPR says, unlike the late-onset form of the disease, doctors can say with certainty that people with the mutation will get the disease and even estimate when it will strike. While this makes people like Rosemary Navarro, who has the mutation — as did her mother — not look forward to her birthday, it gives researchers a way to study the disease as it develops and progresses, NPR says.
Navarro and others like her have enrolled in Alzheimer's disease studies, including an international network led by Washington University School of Medicine, NPR adds, and though it's not certain the projects will benefit them, the research participants hope it might help their children. So far, it reports that the research network has found that amyloid plaques appear in patients' brains before symptoms do as well as established a timeline of disease progression that might inform drug development.
"What I went through with my mom I wouldn't wish on anyone," Navarro tells NPR.