To better assess the status of glial cells in the olfactory bulbs and in the brainstem, we used GFAP (glial fibrillary acidic protein) to identify astrocytes (Fig. 2D–R) and IBA-1 (ionized calcium-binding adapter molecule 1) to identify microglial cells (Supplementary Fig. 5P-AD) by immunohistochemistry. This evidence concerns the gene GFAP and Alzheimer disease.