High-Resolution Genomic Analysis of Human Mitochondrial RNA Sequence Variation

RNA Heteroplasmy Like nuclear DNA, the mitochondrial genome has to be posttranscriptionally modified to function properly; however, among individuals, mitochondrial RNA (mtRNA) transcripts vary in ways that are poorly understood. Hodgkinson et al. (p. 413 ) looked at mtRNA editing events and posttranscriptional methylation in more than 700 individuals. Interestingly, variation at the ninth position within transfer RNAs showed a high frequency of variation that, in some cases, is genetically attributable.