TREM2 and Alzheimer disease: From Alzheimer’s disease-GWAS, rs4938933 which is upstream of MS4A450 and rs610932 which is in the promotor of MS4A6A51 have been reported as genome-wide significant and recently, both MS4A4A and MS4A6A have been shown to modulate TREM2, a component of a transmembrane receptor-signalling complex that is important in microglial activation and function.52