GPR158 and Alzheimer disease: Recently, using the Gene Expression Omnibus (GEO) database, researchers compared the temporal cortex of Alzheimer’s disease (AD) patients to cognitively normal samples, and identified GPR158 as one of the hub genes that is significantly differentially expressed and enriched in synaptic function associated with learning memory according to Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses [17].