ADDI's editorial take

What is it and what does it include? 

We applied Next-Generation Sequencing (NGS) to miRNAs from blood samples of 48 AD (Alzheimer's Disease) patients and 22 unaffected controls, yielding a total of 140 unique mature miRNAs with significantly changed expression level. Of these, 82 were higher and 58 lower abundant in samples from AD patients. We selected a panel of 12 miRNAs for a qRT-PCR analysis on a larger cohort of 202 samples including not only AD patients and healthy controls but also patients with other CNS illnesses: Multiple Sclerosis, Parkinson's Disease, Major Depression, Bipolar Disorder, Schizophrenia, and Mild Cognitive Impairment, which is assumed to represent a transitional period before the development of AD. 

Has this dataset helped researchers understand Alzheimer’s and other dementias better? 

Of course!  

Alzheimer disease, miRNA, Biomarker, Next-generation sequencing, Quantitative Real Time PCR:  

miRNA target enrichment analysis of the selected 12 miRNAs indicates an involvement of miRNAs in nervous system development, neuron projection, neuron projection development and neuron projection morphogenesis. Using this 12-miRNA signature, we differentiate between AD and controls with an accuracy of 93%, a specificity of 95% and a sensitivity of 92%. The differentiation of AD from other neurological diseases is possible with accuracies between 74% and 78%. The differentiation of the other CNS disorders from controls yields even higher accuracies. 

In conclusion the data indicate that deregulated miRNAs in blood might be used as biomarkers in the diagnosis of AD or other neurological diseases. 

July 2013 – DOI:  genomebiology.biomedcentral.com/.../gb-2013-14-7-r78