When Sonia Vallabh’s mother died as a result of prion disease in 2010, she quickly found out that she, too, had inherited a genetic mutation for the same disease that had claimed her mother’s life.

Add Yahoo as a preferred source to see more of our stories on Google. CAMBRIDGE, Mass. ‒ Sonia Vallabh watched helplessly as her 51-year-old mother rapidly descended into dementia and died. It didn't ...