Two new studies have identified a specific gene called TREM2 that seems to greatly increase the risk for Alzheimer’s disease and point to the role that inflammation may have in this disease.

The first study out of Iceland sequenced the genomes of 2,251 people who lived in that country. This team identified the TREM2 mutation as being involved in Alzheimer’s disease and then confirmed their findings in genetic samples taken from people who lived in Norway, Netherlands, Germany and the United...