We found possibly pathogenic genetic variants in SORL1 and MTHFD1L genes and other risk variants in CHAT, ABCA7, and APOE genes segregating in a Colombian multigenerational family with EOAD, suggesting an oligogenic model where multiple genetic factors may be interacting in different biological pathways related with the Aβ production and/or clearance, contributing to the risk of AD. Here, CHAT is linked to Alzheimer disease.