A Novel protective Protein Variant that Colocalizes with Kuru Exposure

Kuru is a type of spongiform encephalopathy, indicating that it is a prion disease. Kuru almost exclusively affected the population within the eastern highlands and province of Papua New Guinea.  Within the population the disease became epidemic for a period of time as the disease was transmitted between individuals in the community. After anthropologic inspection, the disease was only found to be transmitted to females and young children under the ages of six, excluding males after the age of six.  IT was identified that the disease was passed through ritualistic cannibalism of diseased relatives, thereby being the mechanism of transmission. The disease was eradicated in the 1950’s when government officials in the area ensured prohibition of cannibalism.  The disease however serves as a model for other forms of spongiform encephalopathy as other forms are still existant today, as Creutzfeldt-Jacob, and bovine spongiform encephalopathy in animals.

Genetic and clinical genealogic assessments of 3000 persons from the regions including those that participated in mortuary feasts were studied for variant alleles critical in resistance for developing Kuru.  It was found that most individuals are heterozygous for the understood resistance factor at codon 129 of the prion protein gene PRNP.  More interesting however is a new identified prion resistance factor being the 127V polymorphism.  This variant has only been found in individuals within the communities that have been exposed to Kuru indicating that this is a developed resistance to the disease. This variant has developed during the epidemic and represents a significant progression of recent selection in humans.

N Engl J Med 2009; 361:2056-2065November 19, 2009http://www.nejm.org/doi/full/10.1056/NEJMoa0809716

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