SNORD90: SNORD90 is a type of small nucleolar RNA (snoRNA) that is upregulated in SH-SY5Y FUS KO cells and is also enriched in sporadic ALS patients [PMC9941101]. In SH-SY5Y FUS KO cells, elevated levels of SNORD90 were observed alongside hypermethylation of 18S-Um354 and 18S-Cm1272, which are the corresponding guide snoRNAs [PMC9941101]. SNORD90 expression and methylation at SSU-U354 were found to differ in DLBCL cell lines compared to RLNs (reactive lymph nodes) [PMC8210301]. DLBCL tumor samples also showed considerable variation in SNORD90 expression and methylation at SSU-U354, with the mean value falling between that of cell lines and RLNs [PMC8210301]. SNORD90 is a box C/D snoRNA that guides the 2'-O-methylation of rRNA, along with other snoRNAs such as SNORD20, SNORD69, SNORD63, and SNORD101 [PMC8188706]. These snoRNAs are found in significant amounts in EV-enriched sweat samples, with SNORD20 representing over 40% of the total snoRNAs present [PMC8188706].