In a new paper in Nature Medicine, an international team of neurologists makes the compelling case that people with two copies of a gene called APOE4 are not just at risk of Alzheimer’s – they have a distinct form of the disease and are almost certain to develop its telltale brain plaques by age 65.

The finding comes with caveats but still has near-term implications for studying, diagnosing and treating the disease – especially given the advent of drugs like Leqembi, made by Eisai and Biogen, and donanemab, made by Eli Lilly and Company. It should also motivate the field to push further into treatments that specifically target the protein encoded by this gene.