TREM2 and neurodegenerative disease: The signature found in this study includes both factors reported to be beneficial in the context of ALS (Igf1, Grn, Trem2, Tyrobp, etc.), and factors known to be detrimental (Mmp12, Optn, Cybb, etc.), as well as some like Spp1, Gpnmb, and Itgax recurrently found in neurodegenerative diseases.