Most strikingly, we show that citrullinated proteins are overwhelmingly enriched in protein aggregates and predominantly colocalized with myelin protein PLP and MBP (Figs. 6, 7, 8, 9, 10), suggesting that citrullinated proteins are a new class of proteins that aggregate in the white matter in ALS. Here, MBP is linked to amyotrophic lateral sclerosis.