Genome sequencing in cytogenetics: Comparison of short-read and linked-read approaches for germline structural variant detection and characterization

Mol Genet Genomic Med. 2020 Mar;8(3):e1114. doi: 10.1002/mgg3.1114. Epub 2020 Jan 27.

Abstract

Background: Structural variants (SVs) include copy number variants (CNVs) and apparently balanced chromosomal rearrangements (ABCRs). Genome sequencing (GS) enables SV detection at base-pair resolution, but the use of short-read sequencing is limited by repetitive sequences, and long-read approaches are not yet validated for diagnosis. Recently, 10X Genomics proposed Chromium, a technology providing linked-reads to reconstruct long DNA fragments and which could represent a good alternative. No study has compared short-read to linked-read technologies to detect SVs in a constitutional diagnostic setting yet. The aim of this work was to determine whether the 10X Genomics technology enables better detection and comprehension of SVs than short-read WGS.

Methods: We included 13 patients carrying various SVs. Whole genome analyses were performed using paired-end HiSeq X sequencing with (linked-read strategy) or without (short-read strategy) Chromium library preparation. Two different bioinformatic pipelines were used: Variants are called using BreakDancer for short-read strategy and LongRanger for long-read strategy. Variant interpretations were first blinded.

Results: The short-read strategy allowed diagnosis of known SV in 10/13 patients. After unblinding, the linked-read strategy identified 10/13 SVs, including one (patient 7) missed by the short-read strategy.

Conclusion: In conclusion, regarding the results of this study, 10X Genomics solution did not improve the detection and characterization of SV.

Keywords: 10X Genomics: Illumina; bioinformatics; genome sequencing; structural variants.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / diagnosis
  • Abnormalities, Multiple / genetics
  • Chromosome Disorders / diagnosis
  • Chromosome Disorders / genetics*
  • Cytogenetics / methods*
  • Genetic Testing / methods*
  • Genomic Structural Variation*
  • Germ-Line Mutation
  • Humans
  • Intellectual Disability / diagnosis
  • Intellectual Disability / genetics
  • Whole Genome Sequencing / methods*