British scientists have found evidence that the biological seeds of Alzheimer’s disease could be passed on through medical procedures – though specialists said the risk of transmission was largely theoretical.

Researchers involved the study found that the transmissible prions in eight patients appeared to make some more vulnerable to Alzheimer’s disease along with CJD, or Creutzfeldt-Jakob disease.

Study’s lead author John Collinge, a University College London professor and director of the Prion Unit said in a statement that the find they came across their study was quite surprising.

While Alzheimer’s is a common disease of the elderly, it is highly unusual to see amyloid deposits in the brains of relatively young people, he said.

Even the mention of a possible link between Alzheimer’s disease brain pathology and the use of human growth hormone has the potential to prompt wider concern among the public about the origins of dementia.

Brains belonging to eight victims of Creutzfeldt-Jakob disease (CJD), the human form of “mad cow disease”, were looked at by researchers at the National Hospital for Neurology and Neurosurgery.

Misfolding of the amyloid-beta proteins is a hallmark of Alzheimer’s.

But they stress it does not mean that Alzheimer’s is contagious and say more work needs to be done to establish the risk. “Our current data have no bearing on dental surgery and certainly do not argue that dentistry poses a risk of Alzheimer’s disease”.

However, the findings of a study into eight people who were given growth-hormone injections when they were children have raised the disturbing possibility that Alzheimer’s can be transmitted under certain circumstances, when infected tissues or surgical instruments are passed between individuals. So far research on similar diseases on animals have shown that drugs can help in clearing away the protein and thus may slow down progression of the disease.

According to a report from The Guardian, The research was carried out by researchers in the UK. Nor do they suggest that all patients with Alzheimer’s will develop CJD, or vice versa.

“It is very well-known from other studies that one type of rogue protein can predispose to accumulation of another”. Each person developed CJD after human growth hormones were injected between 1958 and 1985.

The evidence points to the hormone carrying “seeds” of the Alzheimer’s protein into the patients’ brains as well as CJD.

For now, the findings only apply to those who may have received injections of growth hormone prior to 1985, before the treatment switched to entirely synthetic sources.

There is also no evidence that any surgical procedure used today, including blood transfusions, routine surgery or dentistry, can transfer Alzheimer’s to a person from another person, because the researchers did autopsies on people who were injected with material derived from cadavers.