One in five people carry a gene that appears to protect against Alzheimer’s disease and Parkinson’s disease, according to a new study. Stady in the United States of America.

An analysis of the medical and genetic data of hundreds of thousands of people found that having this genetic variant, called DR4, reduces a person’s odds of developing either condition by more than 10%, on average.

Experts say this discovery could one day lead to a vaccine that could slow or stop the progression of these conditions.

Credits: sudok1/istock

The study found that people with a specific gene had greater protection against Alzheimer’s disease

The international team, led by Stanford University in California, combined databases from several countries to compare the incidence and age of onset of Alzheimer’s and Parkinson’s disease among people with the genetic variant.

They found that people who had the gene were less likely to develop the disease, and those who had the gene were diagnosed later than those who did not have it.

In a previous study, researchers had already found that carrying the DR4 gene appeared to protect against Parkinson’s disease. So they decided to conduct a new study to make sure the effect would be similar in Alzheimer’s cases.

The researchers also analyzed data from the autopsy brains of more than 7,000 Alzheimer’s patients, and found that those with DR4 had fewer tangles of a protein called tau.

They said their findings suggest that tau, a major player in Alzheimer’s disease, may also play a role in Parkinson’s disease.

The team explained that a vaccine that makes DR4 “work harder” could one day be developed to slow or prevent the progression of Alzheimer’s and possibly Parkinson’s. However, this would only benefit one in five people who carry the genetic variant.