ApoE Variant/Entorhinal Cortex Thickness (IMAGE) NIH/National Institute of Mental Health Caption MRI scans revealed that children and adolescents with the ApoE4 gene variant, which is associated with Alzheimer's disease, had a thinner entorhinal cortex, the first brain area to be affected by the brain disorder. Youth with the much rarer ApoE2 variant, thought to protect against Alzheimer's, had the thickest cortex. The vertical lines in the graph show ranges of thickness, with the red dots being the averages. Credit Philip Shaw, M.D., NIMH Child Psychiatry Branch Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.