Scientists have discovered that harmful ‘tangles’ of protein linked to Alzheimer’s disease, which damage or destroy brain cells, can be transmitted from one brain to another.
The study, conducted by UK, German and Swiss scientists, looked at healthy mice which had been injected with brain tissue from affected animals. The results showed that the mice went on to develop the same defect themselves after destructive knots of protein fibres, called tau tangles, spread through their brains.
Although experts pointed to similarities with variant CJD - the human form of mad cow disease - they stressed that there was no evidence that Alzheimer’s was contagious and could be ‘caught’ through blood contamination.
Lead researcher Dr Michel Goedert, of the Medical Research Council laboratory of Molecular Biology in Cambridge, explained: ‘This research in mice does not show that tau pathology is contagious or that it can spread easily from mouse to mouse. What it has revealed is how tau tangles spread within brain tissues of individual mice.
‘It suggests that tangles of proteins that build up in the brain to cause symptoms could have some contagious properties, within brain tissue but not between mice that haven’t been injected with tissue from another mouse and certainly not between people.’