At the level of protein TREM2 was found to be significantly down-regulated in AMD retina in both whole retina and the macular region to respectively 0.54- and 0.22-fold of controls (Fig 1D–1F; data not shown); hence both miRNA-34a increases and TREM2 deficits were found to be co-localized within the same retinal sample (Fig 1A–1C). Here, TREM2 is linked to age-related macular degeneration.