Sequencing ancient RNA in bioarchaeology - Review

First-Generation Sequencing (FGS) revolutionized molecular biology in general, and bioarchaeology in particular. That allowed to study ancient DNA (aDNA) remains for the first time. Second-Generation Sequencing (SgS) further improved throughput, reducing time and cost per sequenced nucleotide base. Most importantly, it allowed to sequence full ancient-genomes, like the ones of Neanderthals. Third-Generation Sequencing (TGS) improved even more SGS throughput, also allowing to sequence single molecules, without requiring previous amplification or modification steps. That is revolutionary, overcoming putative biases associated to such steps. This opens the door for true-direct RNA sequencing [without retrotranscription into complementary DNA (cDNA)], including ancient RNA (aRNA). Different TGS platforms are arising, promising exciting new discoveries on bioarchaeology for both aDNA and aRNA.