What Causes Prion Disease?
Most cases of prion disease are sporadic, meaning scientists don’t understand what initiates the disease process. The basic mechanism of CJD, as in any prion disease, involves a change in the 3-dimensional shape of the normal prion protein in the brain to an abnormal pathogenic shape. This pathogenic protein, also simply called a “prion”, acts to convert other normal prion proteins into pathogenic prions, simply by binding to them. In the end, the accumulation of prions kills brain cells. Some cases are iatrogenic, in which a person has been exposed to contaminated brain tissue (i.e., by injection of growth hormone, corneal transplant, or surgical instrument). Familial CJD accounts for approximately 15% of all cases. Sometimes taking a thorough family history can help trace the familial form of the disease. Familial CJD is due to the specific mutations, or defects, in the prion protein gene. The age of onset is often younger than usual (less than 55 years) and the duration of the disea
