Transcriptomes include coding and non-coding RNAs and RNA fragments with no apparent homology to parent genomes. Non-canonical transcriptions systematically transforming template DNA sequences along precise rules explain some transcripts. Among these systematic transformations, 23 systematic exchanges between nucleotides, i.e. 9 symmetric (X ↔ Y, e.g. C ↔ T) and 14 asymmetric (X → Y → Z → X, e.g. A → T → G → A) exchanges. Here, comparisons between mitochondrial swinger RNAs previously detected in a complete human transcriptome dataset (including cytosolic RNAs) and swinger RNAs detected in purified mitochondrial transcriptomic data (not including cytosolic RNAs) show high reproducibility and exclude cytosolic contaminations. These results based on next-generation sequencing Illumina technology confirm detections of mitochondrial swinger RNAs in GenBank’s EST database sequenced by the classical Sanger method, assessing the existence of swinger polymerizations.
Part of the book: Mitochondrial DNA