**2.1. Detection of swinger RNAs**

We used GenBank's BLASTn ('somewhat similar sequences' with default alignment parameters) [49] for in-silico alignment searches between each of the 23 swinger-transformed versions of the human mitogenome (NC\_012920) and transcriptomic data in GenBank's Sequence Read Archive (SRA) (SRX084350-SRX084355 and SRX087285), sequenced by RNA-Seq, Illumina HiSeq 2500 technology [48]. Alignments with more than 80% identity were recorded and used as a swinger RNA candidate for further analysis.
