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sheep eating grass upon which the placenta of another sheep had fallen. Not only was it infectious but, as scientists also discovered, scrapie could be positively identified by the presence of distinct vacuoles marking a sheep’s neurons like a bunch of spongy holes, an observation made possible with a basic microscope. This hypothesis and observation became integral starting points for the scientific community’s understanding of the disease. Meanwhile, in an entirely unrelated context, an unknown German scientist named Hans Gerhard Creutzfeldt published in 1920 an obscure paper on “a Strange Focual Disease of the Central Nervous System” that he observed in a human patient he called “Berta E.” Remarking upon her rapidly diminishing coordination, as well as her rapid mental deterioration \(“she thought Creutzfeldt found the loci of degeneration in “unusual brain lesions” that were odd enough to categorize Berta E:s case as a new neurological disorder. When another German scientist named Alfons Maria Jakob published a paper describing several patients showing symptoms strikingly similar to Berta E.’s, a colleague of both men coined the term “Creutzfeldt-Jakob disease,” hoping way back in 1922 that the condition “will come to be thoroughly defined, in anatomical and clinical terms.” Little could he have known the stealth the disease would use to elude such definition. Although nobody made the connection in the 1920s, we now know that scrapie and CJD were different adaptations of the same disease, a disease we now call Transmissible Spongiform was so rare, Creutzfeldt’s and Jakob’s articles gathered dust for 30 years, leaving it to veterinarians to struggle helplessly, for example, with the scrapie epidemic that swept Scotland in 1937. But again, in an entirely different context, new discoveries emerged to bring scientists closer to that ever-evasive definition. Watson and Crick demonstrated the structure of DNA in 1953, thus giving birth to the field that would ultimately explain the essential connection between scrapie and CJD and, later, BSE and CJD: molecular biology. With ideal communication, what scientists were coming to learn about proteins and nucleic acids in the lab might have had an immediate impact on animal pathologists’ understanding of scrapie’s infectious, transmissible, and hereditary qualities in the field. But, as Maxime writes, “A typical researcher has good knowledge about work in his own field, a little about related fields, and hardly any about more remote subjects?’ And dizzy sheep up in the Highlands were nothing if not remote. Were it not for the 1957 discovery of a Papua New Guinea community that made a culinary delicacy of each other’s brains, scientists may never have discovered the essential link between scrapie and CJDa pivotal connection that would alert health officials to the epidemiological ramifications for humans when the cows began to go mad in the 1980s. Ritual cannibalism among the Fore people resulted in a disease called kuru. Turns out that kuru exhibited the same spongy cerebral lesions found in scrapie and CJD. With this suggestive link effectively established, the scientific community was finally piqued. After all, with people keeling over the way sheep were keeling over, the stakes were raised, money made available, prizes to be won. Concerns focused on contagion and transmissibility. First, there was the question of how the disease spread was it infectious or hereditary? Second, could it be transferred from one species to another? The regrettable answer to the latter question was yes. Scientists successfully transmitted scrapie to mice and kuru to chimps. Whether or not transmission to humans was possible could only be hypothesized, of course, but answers here were tragically forthcoming. What about contagion? Well, here’s where that biology textbook came short: TSE is both hereditary and infectious and the causative agent in both forms of infection is a protein called a prion. The prion violated everything that a molecular biologist worshipped as sacred. “It is?’ Maxime writes, “a furtive protein that can cross the intestinal barrier, insinuate itself into the nervous system, crawl up to the brain, and enter the neurons and destroy them.” But because it is a proteinand not a foreign virus the body cannot produce the antibodies continued on page 43 8/13/04 THE TEXAS OBSERVER 25