Among the upregulated DDEGs in SGNs, Sncb encodes a member of a small family of proteins that inhibit phospholipase D2, which is abundant in neurofibrillary lesions of patients with Alzheimer’s disease and has been reported to trigger oxidative stress and inflammatory responses in the aged retina (Hadrian et al., 2019). Here, PLD2 is linked to early-onset autosomal dominant Alzheimer disease.