Through extensive research, collaboration, and ultimately the death of a chimpanzee, scientists were able to establish that Kuru is a bacterial disease. This identification raises obvious ethical questions regarding the reach and scope of scientific research. Furthermore, it demonstrates many of the challenges that scientists face while researching controversial and groundbreaking fields.
Scientists researching this disease had to fight most of the existing knowledge in the scientific community regarding bacterial diseases. As the RCSB Protein Data Bank explains in their “Molecule of the Month: Prions” article, when the normal form of a Prion Protein (PrP) cell folds, it wreaks havoc on the brain and prevents it from functioning properly. This fold can occur randomly and independently, but in Papa New Guinea, the folded PrP cell was almost entirely transmitted through ingestion. The misfolded proteins can spread throughout the persons’ body that consumed the infected flesh, and this causes the neurological decay.
Scientists had never encountered this protein folding before the PrP, and they had never encountered an infectious disease like Kuru. Carriers of the disease did not exhibit any traditional signs of a bacterial disease. Most importantly, there was no immune system response. The body made no apparent attempts to combat the disease. This contradicted some of the most fundamental and widely accepted knowledge regarding bacterial diseases at the time, and it took extensive research to support the PrP folding theory.
Finally, while testing on animals is generally viewed as controversial, I think that testing on animals in the case of Kuru made a lot of ethical and scientific sense. Human lives were clearly at risk; hundreds and hundreds of people had already died of the disease, with little to no scientific progress regarding the nature of the disease. Through the death of one chimpanzee researchers were able to save human lives. That tradeoff makes a lot of sense to me. Even though the testing only had the potential to save human lives, people had died, and the scientific and global community deserved answers. The case of Mad Cow disease is more ambiguous. People are worried that the collapsed PrP in cows that causes Mad Cow disease could potentially spread to humans. Scientists want to conduct tests to see of the PrP can make a species jump from cows to chimpanzees. This result is less conclusive than the first example. Demonstrating that a disease can be transmitted from a cow to a chimpanzee does not prove that a disease can be transmitted from a cow to a human. Furthermore, demonstrating that a disease is not transmitted from a cow to a chimpanzee does not prove that the disease can’t make the jump from cow to human. The test is less conclusive than the first chimpanzee test referenced, and its results simply don’t warrant the potential death of another animal. These ethical questions continue to arise as Scientists explore the prion protein.