The ε4 allele of the apolipoprotein E gene (APOE*ε4) is a well-established genetic risk factor for Alzheimer disease (AD), but the mechanisms through which this variant influences AD risk remain unclear. As reported in Nature, a new study by Berislav Zlokovic and colleagues demonstrates an association between APOE*ε4 carrier status and blood–brain barrier (BBB) breakdown, which could contribute to cognitive decline.
The investigators recruited 435 participants aged ≥45 years, 245 of whom underwent dynamic contrast-enhanced MRI of the brain to measure BBB integrity. APOE*ε4 carriers — that is, people with the APOE*ε3/ε4 or the APOE*ε4/ε4…
