Rare gene linked with ‘protecting’ woman from Alzheimer’s

Scientists have linked a rare gene mutation with protecting a woman from developing symptoms of Alzheimer’s disease.

Researchers say it could be the first known candidate for a gene that has the potential to be used in the development of interventions to halt the progression of the disease.

Researchers found one person in a study of 1,200 individuals in Colombia, for whom Alzheimer’s disease is extremely likely to develop, due to genetic predisposition.

The woman, from a large extended family with more than 6,000 living members, did not develop mild cognitive impairment until her 70s – nearly 30 years after the typical age of onset.

Like her relatives who showed signs of dementia in their 40s, the patient carried the E280A mutation in a gene called Presenilin 1 (PSEN1).

This gene has been shown to cause early onset Alzheimer’s disease, according to research published in Nature Medicine.

Analysis showed the woman had a high degree of brain amyloid pathology, a hallmark of the disease, but did not present with symptoms associated with the disease.

Researchers found she also had a rare variant of the APOE gene, called Christchurch.

They suggest this may have counteracted the detrimental effects of the PSEN1 mutation, which could have protected her against the disease.

Co-author Dr Yakeel Quiroz, researcher at Massachusetts General Hospital, said: “This single case opens a new door for treatments of Alzheimer’s disease, based more on the resistance to Alzheimer’s pathology rather than on the cause of the disease.”

Dr Fiona Carragher, chief policy and research officer of the Alzheimer’s Society, said: “This is a rare example where the study of just one person could change the thinking of a whole research field.

“This breakthrough opens up a new and promising avenue of Alzheimer’s research, although further studies with larger numbers are needed.”