In a report by the Timesonline.co.uk, American and Japanese scientists have produced cattle lacking the prion protein, which malfunctions to cause “mad cow” disease and other forms of the ‘prion’ diseases in humans and animals. Cloned cattle have been created by these scientists in an experiment that suggests that cows can be genetically modified to be resistant to the devastating brain condition of the Creutzfeldt-Jakob Disease. The Creutzfeld-Jakob disease is known to be caused by prion in cows and is not the only prion disease afflicting both animals and humans since the 1950’s.

The report suggests that the cloning of cattle could pave the way for breeding cattle that cannot infect people with prion disease by removing the prion gene (PrPc) completely. This method was used to clone eight Holstein bulls. Tests and comparisons with normal bulls suggest that they are completely healthy, though it was admitted that more research is needed to confirm this. “At over 20 months of age, the cattle are clinically, physiologically, histopathologically, immunologically and reproductively normal,” Dr Richt said. “Prion protein-deficient cattle may be a useful model for prion research.”

The scientists have also said that a more realistic prospect would be to use prion-free cattle, the genetically modified cattle or ‘cloned’ cattle to be more specific in other words, as a source of bovine products for use in medicine and medical research. Calf serum, for example, is used in the culture of vaccines. The research is published in the journal Nature Biotechnology.

What the report does not mention is that there is evidence that prion genes may have a normal function in maintenance of memories over a long period of time and that they are adaptive conduits of memory and inheritance. A report titled “Prions as adaptive conduits of memory and inheritance” by the Whitehead Institute for Biomedical Research, Nine Cambridge Center, Cambridge, MA 02142, USA, (shorter@wi.mit.edu) showcases definitive evidence for the prion hypothesis and discusses examples in which prion-encoded heritable information has been harnessed during evolution to confer selective advantages. The report further describes situations in which prion-enciphered events might have essential roles in long-term memory formation, transcriptional memory and genome-wide expression patterns.