There used to be a regular stream of stories in the media about a cure for cancer being just around the corner. After several decades cancer is much better understood but there is still no ‘magic bullet’.

Alzheimer’s disease is the ‘new cancer’ with millions of pounds being spent looking at the cause of the disease. There was a frisson of excitement in the media in April when a study in the US found that in mice, in the early stages of the disease, some immune cells that normally protect the brain undergo changes and begin to chew up arginine, an important amino acid.

The researchers found they could stop the immune cells destroying arginine with a drug called difluoromethylornithine (DFMO). When they tested it on the mice, it prevented the brain plaques and memory loss that are characteristic of Alzheimer’s disease.

This is interesting but only serves to highlight that scientists haven’t been able come up with a cure or treatment for Alzheimer’s disease because they still don’t know exactly what causes it. They can see what happens to patients and predict what will happen but don’t know how or why – yet.