These genes included fine-mapped high-confidence AD-risk variants linked to over 20 genes in microglia, such as BIN1, PICALM, SPI1, TREM2, SORL1, USP6NL and ABCA7. A subsequent study using single-cell chromatin looping data from the prefrontal cortex identified chromatin interactions linking AD-risk variants to INPP5D and MS4A7 in microglia (121). Here, PICALM is linked to Alzheimer disease.