MS4A1 and Alzheimer disease: Beyond the well-known MS4A1 (CD20), convergent evidence from neurodegeneration highlights membrane-spanning 4-domains A6A, MS4A6A,as a potential candidate gene in microglial biology: common variants at the MS4A locus associate with Alzheimer’s disease risk, with signals near MS4A6A and nominal brain eQTL effects [10,11].