Kuru: Uncovering mysterious disease that left entire villages in Papua New Guinea without women

In the mid-20th century, the Eastern Highlands Province of Papua New Guinea was struck by a mysterious disease, causing entire villages to lose adult women.

Fore people at the center of the epidemic call it Kuru The term tremors refers to the tremors that occur before death occurs before a person loses control of their limbs and body functions.

The tribe remained relatively isolated from the rest of the world until the 1930s, but by the height of the epidemic in the 1950s, it attracted the attention of researchers around the world trying to understand the disease, which has never been able to Get an explanation.

After ruling out contaminants, researchers hypothesized that it might be hereditary until it was discovered that kuru was spread through Falls’ traditional mortuary feasts, during which people ate the bodies of their deceased relatives.

Kuru, a type of prion disease, is a progressive neurodegenerative disorder caused by changes in the shape of normal prion proteins in the body. The most likely explanation for its spread is that at some point, a person died from a randomly occurring prion disease, such as sporadic Creutzfeldt-Jakob disease (CJD), and the infected tissue was then consumed by the community.

Since according to spiritual beliefs the body is decomposed and eaten in a ritualistic manner, with certain tissues being distributed to certain relatives, women and children are most affected by the disease as they are assigned prions Concentrated brain and spinal cord.

The prevalence of kuru gradually declined in the decades after mortuary feasts were outlawed in the 1950s, but a research center in the UK has been working on prion disease after it experienced an epidemic.

The Medical Research Council’s prion unit at University College London was founded in the wake of BSE, or mad cow disease, which occurs when cattle are crushed and then fed back to cattle, and crossed the species barrier in 1995, when young were infected. Mad cow disease.

New research led by the department and published this week in the American Journal of Human Genetics provides the most comprehensive genetic study to date of residents of the Eastern Highlands and examines the impact of the kuru epidemic on migrant flows in the region.

Fresh genetic analysis

It was previously thought that Kuru caused a decrease or even a complete cessation of intermarriage between the Fore and neighboring communities, as they associated the disease with witchcraft.

The new genetic analysis found no evidence of a reduction in overall immigration from areas most affected by kuru, or an end to the patriarchal practice of brides moving to live closer to their husbands’ families.

Instead, we observed significant bias against women among immigrants entering areas with high rates of kuru, the authors write. The analysis shows that the proportion of women in the migrant population in areas with a high incidence of kuru is 25% higher than in areas with zero/low incidence of kuru.

This may reflect the ongoing practice of patriarchy [where a newlywed couple lives near the husbands family] The paper concludes that despite documented evidence of the fear and stress kuru causes in communities.

The Papua New Guinea Medical Research Institute (PNGIMR) recruited field staff from affected and neighboring populations to collect genetic samples through long-term community engagement, which were then analyzed by researchers in London and Copenhagen.

The researchers conducted a genetic analysis based on whole-genome genotype data from 943 people from 21 language groups and 68 villages in the eastern highlands of Papua New Guinea in the region, including 34 villages from the Southern Fore language group, which is affected by Influenza affects the most vulnerable groups.

The laboratory study was approved by the PNGIMR Advisory Committee and the University College London Institute of Neurology Research Ethics Committee, with verbal consent obtained from all participants before any samples were obtained and through consultation with village leaders, community, families and individuals.

Early genetic studies of the Fore suggested that female survivors carry mutations in genes encoding prion proteins that may make them resistant to kuru.

Professor Simon Meade, consultant neuroscientist and clinical lead at the UK’s National Prion Clinic, said: “We have found evidence that the Fore population is evolving to protect themselves against kuru, but past research in this area Very few, so we cannot make confident inferences about evolution without a deep understanding of the genetics of the populations involved.

The question of whether female migration was dramatic enough to alter the genetic makeup of traditional island communities remains unanswered, said Dr. Irene Gallagher Romero, a human genomics and evolution researcher at St. Vincent’s Medical Research Institute.

Romero said the study found a surprising degree of demographic structuring, or unique genetic groups, in the area, but if strict village boundaries did break down, a smaller degree of demographic structuring would be observed.

Surprisingly, she said, the study shows how genetics can add another dimension to the history of a relatively unknown population.

[Anthropology] The stories genetics tells are mostly complementary, but there are some inconsistencies.

For example, studies have found that some villages that speak different languages ​​are genetically similar, while some communities that speak the same language are genetically different.

So it’s great to be able to look at human societies and populations in a variety of ways.

Another important finding is that there are huge genetic differences between language groups. The researchers found that there were greater differences between communities in Papua New Guinea than between Spain and Finland, even though some of the groups were only 45 kilometers apart. Gallagher Romero attributes this to marriage customs within small communities.

Colin Masters, Laureate Professor of Neuropathology at the University of Melbourne, said the study illustrates how epidemics and epidemics that kill millions of people have the potential to alter a population’s genetic code.