Why Are There Many Mirna Or Noncoding Rna In My Mrna-Seq Data?

Question

[Pinji Lei]

I'm a freshman in bioinformatics, and when I do the RNA-seq data analysis I found many miRNA or noncoding RNA in my results, why?

[Michael]

Please try to be more specific: "the RNA-seq data analysis" and "many miRNA" is about zero information to deal with. Also, why would it bother you? Is your aim to improve your RNA-seq protocol?

Answer 1

[Michael]

This is not really a bioinformatics question but a sequencing protocol question, maybe better asked giving more details on seqanswers. But the short answer is: most likely because they are there.

RNA-seq protocols targeted at eukaryote mRNA include steps to deplete ribosomal RNA, or fish only mRNA with polyA tail. But none of these protocols is 100% efficient.

[Edalat]

Dear Michael I have some human non coding RNA-seq data,for getting diff-exp of miRNA,I should trim length between 18 to 30 befor starting? why Avg. Sequence length is 51,can I use these data for getting diff-exp of lncRNA too?