The focus was a gene called APOE, which comes in three common versions: ε2, ε3, and ε4. Every person carries two copies. For decades, ε4 has been labeled the “high-risk” variant, while ε2 is thought to be protective. ε3, the most common version, has largely been treated as neutral.
93% of Alzheimer’s Cases Could Be Tied to This One Gene
