We recently developed a multiplex diagnostic kit, QPLEXTM Alz plus assay kit, which captures amyloid-β1-40, galectin-3 binding protein, angiotensin-converting enzyme, and periostin simultaneously using microliters of peripheral blood and utilizes an optimized algorithm for screening Alzheimer’s disease (AD) by correlating with cerebral amyloid deposition. This evidence concerns the gene POSTN and early-onset autosomal dominant Alzheimer disease.