eKLIPse: a sensitive tool for the detection and quantification of mitochondrial DNA deletions from next-generation sequencing data

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Accurate detection of mitochondrial DNA (mtDNA) alterations is essential for the diagnosis of mitochondrial diseases. The development of high-throughput sequencing technologies has enhanced the detection sensitivity of mtDNA pathogenic variants, but the detection of mtDNA rearrangements, especially multiple deletions, is still poorly processed. Here, we present eKLIPse, a sensitive and specific tool allowing the detection and quantification of large mtDNA rearrangements from single and paired-end sequencing data.


The methodology was first validated using a set of simulated data to assess the detection sensitivity and specificity, and second with a series of sequencing data from mitochondrial disease patients carrying either single or multiple deletions, related to pathogenic variants in nuclear genes involved in mtDNA maintenance.


eKLIPse provides the precise breakpoint positions and the cumulated percentage of mtDNA rearrangements at a given gene location with a detection sensitivity lower than 0.5% mutant. eKLIPse software is available either as a script to be integrated in a bioinformatics pipeline, or as user-friendly graphical interface to visualize the results through a Circos representation (https://github.com/dooguypapua/eKLIPse).


Thus, eKLIPse represents a useful resource to study the causes and consequences of mtDNA rearrangements, for further genotype/phenotype correlations in mitochondrial disorders.

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This work was supported by grants from Association contre les Maladies Mitochondriales, and the University and Hospital of Angers.

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Correspondence to Vincent Procaccio MD PhD.

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The authors declare no conflicts of interest.

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Joint First Authors: David Goudenège and Celine Bris.

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Goudenège, D., Bris, C., Hoffmann, V. et al. eKLIPse: a sensitive tool for the detection and quantification of mitochondrial DNA deletions from next-generation sequencing data. Genet Med 21, 1407–1416 (2019) doi:10.1038/s41436-018-0350-8

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  • mitochondrial diseases
  • mitochondrial genome
  • mtDNA deletions
  • next-generation sequencing
  • soft clipping

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