De novo detection of A-to-I RNA editing sites in human mRNAs by massive transcriptome sequencing

Motivations RNA editing is a widespread molecular phenomenon which modifies primary transcripts at specific positions [1]. It occurs in a variety of organisms including human and cooperates with alternative splicing in increasing both proteomic and transcriptomic complexity. RNA Editing can modulate gene expression and affect protein functionality. In human, such phenomenon is highly frequent in brain and its deregulation has been linked to a variety of neurological and neurodegenerative diseases [2]. Many editing events have been identified by next generation sequencing technologies employing massive transcriptome sequencing [3] together with whole genome or exome sequencing. Nowadays numerous RNA-Seq experiments are available through public databases and represent a relevant source of yet unexplored RNA editing sites. Hereafter we propose a simple computational strategy to identify de novo genomic positions enriched in novel potential RNA editing events through a new, two-step mapping procedure.