Identification and analysis of deletion breakpoints in four Mohr-Tranebjærg syndrome (MTS) patients

Nanna Dahl Rendtorff (Lead / Corresponding author), Helena Gásdal Karstensen, Marianne Lodahl, John Tolmie, Catherine McWilliam, Mads Bak, Niels Tommerup, Lusine Nazaryan-Petersen, Henricus Kunst, Melanie Wong, Shelagh Joss, Valerio Carelli, Lisbeth Tranebjærg (Lead / Corresponding author)

Research output: Contribution to journalArticlepeer-review

2 Downloads (Pure)

Abstract

Mohr-Tranebjærg syndrome is an X-linked syndrome characterized by sensorineural hearing impairment in childhood, followed by progressive neurodegeneration leading to a broad phenotypic spectrum. Genetically MTS is caused by pathogenic variants in the TIMM8A gene, including gene deletions and larger contiguous gene deletions. Some of the latter involve the neighboring gene BTK, resulting in agammaglobulinemia. By next-generation mate-pair sequencing we have mapped the chromosomal deletion breakpoints of one MTS case and three XLA-MTS cases and used breakpoint-spanning PCR to fine map the breakpoints by Sanger sequencing. Two of the XLA-MTS cases presented with large deletions (63.5 and 27.2 kb), and the junctional regions were characterized by long stretches of microhomology, indicating that the events have emerged through homologous recombination. Conversely, the MTS case exhibited a small 2 bp region of microhomology, and the regions were not characterized by extensive microhomology. The third XLA-MTS case had a more complex breakpoint, including a 59 bp inverted insertion, thus at least four breakpoints were involved in this event. In conclusion, mate-pair library generation combined with next-generation sequencing is an efficient method for breakpoint identification, also in regions characterized by repetitive elements.

Original languageEnglish
Article number14959
Number of pages7
JournalScientific Reports
Volume12
DOIs
Publication statusPublished - 2 Sep 2022

Keywords

  • Clinical genetics
  • Genetics
  • Molecular biology

Fingerprint

Dive into the research topics of 'Identification and analysis of deletion breakpoints in four Mohr-Tranebjærg syndrome (MTS) patients'. Together they form a unique fingerprint.

Cite this