mRNA was isolated from total RNA using the kit NEBNext Poly(A) mRNA Magnetic Isolation Module (New England Biolabs). NGS libraries were prepared from the purified mRNA using the NEBNext Ultra II RNA Library Prep Kit for Illumina (New England Biolabs). 18 cycles of PCR amplification were applied to all libraries. The final libraries were quantified using the Qubit dsDNA HS assay (Invitrogen) and quality controlled with the Bioanalyzer 2100 DNA HS assay (Agilent). An equimolar pool was prepared with the twenty libraries and submitted for sequencing at the Centro Nacional de Análisis Genómico (CNAG).