SNORA66: SNORA66 is a small nucleolar RNA (snoRNA) that has been studied in various contexts. It has been used as a reference gene for normalization of qRT-PCR data in different studies [PMC7281098] [PMC7737439]. However, its expression level was found to be below the detection level in a large proportion of samples, leading to its exclusion from the analysis of expression level stability [PMC7281098] [PMC7737439]. SNORA66 is part of a family of small nucleolar RNAs that includes SNORA61, SNORA16A, and SNORD99 [PMC8107103]. It has been found to be both upregulated and downregulated in different studies. For example, it was downregulated in certain samples along with other snoRNAs, tRNAs, and miRNAs [PMC9321239]. On the other hand, it was upregulated in low-risk cohorts and served as a protective factor in DLBCL patients [PMC9939161]. SNORA66 has also been used as an endogenous control for miRNA expression normalization in qRT-PCR experiments [PMC7015979]. Additionally, it has been implicated in various biological processes such as DNA transcription and post-transcriptional modification of ribosomal RNAs (rRNAs) [PMC4831167] [PMC6123486]. However, more research is needed to fully understand the clinical value and regulatory mechanisms associated with SNORA66.