Prion mutation yields disease marked by diarrhea
Rare ailment starts in adulthood, attacking gut before brain
By Nathan Seppa
A newly discovered prion disease damages parts of the body far from the brain. The finding unveils a curious new version of these misfolded proteins infamous for causing brain-wasting diseases such as mad cow disease. Researchers report that 11 of 27 people spanning five generations in one family have inherited a prion mutation, which causes the slow-developing but lethal disease.
The report, in the Nov. 14 New England Journal of Medicine, describes the first prion disease known to primarily attack the peripheral nervous system, causing chronic diarrhea and other problems beginning in adulthood. People with the genetic defect did develop cognitive and memory problems but not until their 40s or 50s. Average age at death was 57 for the family members with the disease.