To implement a multi-omic TempO-Seq® DBS test platform and specific tests for Alzheimer’s Disease (AD), Parkinson’s Disease (PD) and Myasthenia Gravis (gMG) using a fingerstick blood sample with the goal of improving diagnosis and reducing health disparities using samples that can be easily collected in a doctor’s office or self-collected.

A gene expression classifier for AD and PD was developed using fingerstick blood spotted on filter paper and the TempO-Seq DBS whole transcriptome mRNA assay (DOI10.3233/JAD-240174). We subsequently validated the measurement of DNA variants (classifying coronary artery disease polygenic risk) and discovered that 903 ProteinSaver cards could be used, permitting measurement of protein biomarkers.

TempO-Seq DBS assays for DNA variants, including APOE4, and protein biomarkers were established and benchmarked against commercial tests.  Fingerstick blood samples were obtained from controls and patients diagnosed with AD, PD, and gMG, spotted on 903 Protein Saver cards, and assayed for mRNA, DNA, and protein biomarkers using TempO-Seq DBS.

Results presented will demonstrate that AD, PD, and gMG-specific molecular signatures were identified, and classification algorithms were established to provide accurate identification of diagnosed patients. Additionally, results will demonstrate the measurement of the APOE4 DNA variant and traditional protein biomarkers in patients diagnosed with AD.

The use of liquid biopsy samples, specifically fingerstick blood, to classify AD, PD and gMG, demonstrates the utility of this approach and the TempO-Seq DBS platform to aid in the process of diagnosing neurodegenerative diseases and neurologic disorders. For AD, the measurement of APOE4 and protein biomarkers enables definitive diagnosis and determination of eligibility for immunotherapy. When self-collected without having seen a neurologist first, TempO-Seq DBS tests can help address health disparities and potentially bring patients into clinical care earlier in the course of their disease.