**1. Introduction**

RNA-seq technology has driven advances in gene expression analysis through new-generation sequencing platforms, as they are versatile, powerful and ensure quality results with accuracy and reproducibility never reached before. This technology generates information that provides meaning to the set of transcripts (transcriptome), opening up possibilities for understanding cell behavior in different environments. RNA is an important component within the cell, since it plays different roles as a messenger regulatory molecule and carrier; and, it is also essential for the maintenance of housekeeping genes [1].

In 2005, the first new generation of sequencing technology was released and has been evolving rapidly [2]. After starting the process of gene expression analysis in bacteria [3, 4] at a more accessible cost, shorter experimental time and without probes, the technology took off and today overlaps other tools used for this purpose, such as microarray technology, until now extremely useful for this type of analysis.

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