A new study suggests people carrying two copies of the APOE4 gene variant may have a distinct genetic form of Alzheimer's disease. This could significantly impact how the disease is researched, diagnosed, and treated.
For decades, scientists have known APOE4 increases Alzheimer's risk. This study, published in Nature Medicine, argues it goes beyond just a risk factor. Researchers analyzed brain scans and biological data from over 10,000 individuals.
Their findings show that by age 65, nearly all participants with two copies of APOE4 (APOE4 homozygotes) had biomarkers linked to Alzheimer's. This suggests a strong link between the gene variant and the disease itself.
The study has sparked debate. While some researchers believe it presents a new form of Alzheimer's, others argue the underlying processes remain similar.
Regardless of the classification, the findings have important implications. Treatments like Leqembi, which targets amyloid buildup in the brain, can cause side effects in APOE4 homozygotes. This study suggests earlier intervention may be necessary for this group.
Furthermore, the research highlights the need for clinical trials focused on preventing Alzheimer's in high-risk individuals, particularly those with two APOE4 copies.
The study's limitations include its focus on a predominantly European population. Further research is needed to understand how APOE4 affects individuals of African descent.
Overall, this research offers valuable insights into the role of APOE4 in Alzheimer's development. It has the potential to pave the way for more targeted prevention and treatment strategies for this devastating disease.