DALLAS: Research has identified the first new human prion disease in 50 years. The paper’s lead author says this new disease is also potentially infectious.
Prion diseases are a rare class of brain disorders that are transmissible between animals of any species, including humans. The archetypal such disease is kuru, which spread through cannibalistic rituals in the Eastern Highlands of Papua New Guinea.
Kuru affected mostly women and children of the Fore tribe, who ate brains and spinal cords of deceased relatives, and subsequently developed body tremors, balance problems and slurred speech. There’s no cure for kuru and sufferers always died. But it no longer strikes as cannibalism in the region has been eliminated.
Other prion diseases include scrapie in sheep and goats and bovine spongiform encephalopathy (BSE) in cows. When transmitted to humans during the “mad cow disease” outbreak in Europe, BSE resulted in variant CJD (vCJD).
The newly described addition to the prion disease canon, Shy-Drager syndrome (SDS) or multiple system atrophy (MSA), was first recognised in the early 1960s and has many features in common with Parkinson’s disease.
The most important of these is that a protein known as α-synuclein (α-syn) accumulates in the brain, in both Parkinson’s and SDS/MSA. This accumulation is very similar to what happens in CJD, where the prion protein (PrP) accumulates, and also in Alzheimer’s disease and other dementias, where two types of proteins, known as amyloid beta (Aβ-amyloid) and tau, build up in the brain.