Alzheimer's Brain Tissue Study Uncovers Three Distinct Disease Subtypes

A study published in Science Advances outlines three distinct Alzheimer's disease (AD) subtypes from brain tissue analysis, reports New Atlas . The team used RNA sequencing to screen more than 1,500 tissue samples, covering five different brain regions. The subtypes were identified according to factors like synaptic signaling, immune activity, mitochondria arrangement, myelination, and specific gene activity. Just one third of cases displayed "typical' AD hallmarks, including less synaptic signaling and higher immune response, in a subtype labeled class C. The research suggests the other two identified subtypes — class A and B — exhibited distinct characteristics. In some cases the subtypes displayed oppositional gene regulation, suggesting these findings could potentially help explain previous clinical trial failures. "These findings lay down a foundation for determining more effective biomarkers for early prediction of AD, studying causal mechanisms of AD, developing next-generation therapeutics for AD, and designing more effective and targeted clinical trials, ultimately leading to precision medicine for AD," said Bin Zhang at the Icahn School of Medicine at Mount Sinai. "The remaining challenges for future research include replication of the findings in larger cohorts, validation of subtype specific targets and mechanisms, identification of peripheral biomarkers, and clinical features associated with these molecular subtypes."