(Undark) – Jennie Erin Smith’s “Valley of Forgetting” explores the genetics of early-onset dementia plaguing a mountain region.

That cause — a hereditary genetic mutation known as E280A — is at the heart of science journalist Jennie Erin Smith’s deeply researched book, “Valley of Forgetting: Alzheimer’s Families and the Search for a Cure.” The gene becomes known as the “paisa mutation” because, as Smith explains, “paisa” in Colombia refers to people from the mountain region that includes Medellín and the surrounding villages. And it’s among these paisa that E280A has made its home, an inheritance that traces back to four sisters who lived in the region during the late 18th and early 19th centuries and that has been handed down to thousands of families in the region.

E280A is not a risk factor for early Alzheimer’s; it is nearly a guarantee of it. (Read More)