Article Text

other Versions

PDF
Original article
Naturally occurring BRCA2 alternative mRNA splicing events in clinically relevant samples
  1. James D Fackenthal1,
  2. Toshio Yoshimatsu1,
  3. Bifeng Zhang1,
  4. Gorka R de Garibay1,
  5. Mara Colombo2,
  6. Giovanna De Vecchi2,
  7. Samantha C Ayoub1,
  8. Kumar Lal1,
  9. Olufunmilayo I Olopade1,
  10. Ana Vega3,
  11. Marta Santamariña3,
  12. Ana Blanco3,
  13. Barbara Wappenschmidt4,
  14. Alexandra Becker4,
  15. Claude Houdayer5,
  16. Logan C Walker6,
  17. Irene López-Perolio7,
  18. Mads Thomassen8,
  19. Michael Parsons9,
  20. Phillip Whiley9,
  21. Marinus J Blok10,
  22. Rita D Brandão11,
  23. Demis Tserpelis10,
  24. Diana Baralle12,
  25. Gemma Montalban13,
  26. Sara Gutiérrez-Enríquez13,
  27. Orland Díez13,14,
  28. Conxi Lazaro15,
  29. kConFaB Investigators16,
  30. Amanda B Spurdle9,
  31. Paolo Radice2,
  32. Miguel de la Hoya7
  1. 1Department of Medicine, University of Chicago, Chicago, Illinois, USA
  2. 2Unit of Molecular Bases of Genetic Risk and Genetic Testing, Department of Preventive and Predictive Medicine, Fondazione IRCCS Istituto Nazionale dei Tumori (INT), Milano, Italy
  3. 3Fundación Pública Galega de Medicina Xenómica-SERGAS, Grupo de Medicina Xenómica-USC, CIBERER, IDIS, Santiago de Compostela, Spain
  4. 4Medical Faculty, Center for Hereditary Breast and Ovarian Cancer, Center for Integrated Oncology (CIO) and Center for Molecular Medicine Cologne (CMMC), University of Cologne and University Hospital Cologne, Germany
  5. 5Service de Génétique and INSERM U830, Institut Curie and Université Paris Descartes, Sorbonne Paris Cité, Paris, France
  6. 6Department of Pathology, University of Otago, Christchurch, New Zealand
  7. 7Laboratorio de Oncología Molecular, Instituto de Investigación Sanitaria San Carlos (IdISSC), Hospital Clínico San Carlos, Madrid, Spain
  8. 8Department of Clinical Genetics, Odense University Hospital, Odense C, Denmark
  9. 9Genetics and Computational Biology Division, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
  10. 10Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, The Netherlands
  11. 11Maastricht Science Programme, Faculty of Humanities and Sciences, Maastricht University, Maastricht, The Netherlands
  12. 12Human Development and Health Academic Unit, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, UK
  13. 13Oncogenetics Group, Vall d'Hebron Institute of Oncology (VHIO) and Universitat Autonoma de Barcelona, Barcelona, Spain
  14. 14Clinical and Molecular Genetics Area, University Hospital Vall d'Hebron, Barcelona, Spain
  15. 15Molecular Diagnostic Unit, Hereditary Cancer Program, IDIBELL–Catalan Institute of Oncology, Barcelona, Spain
  16. 16Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
  1. Correspondence to Dr James D Fackenthal, Department of Medicine, Section on Hematology/Oncology, University of Chicago, Chicago, IL 60637, USA; JimFackenthal{at}gmail.com

Abstract

Background BRCA1 and BRCA2 are the two principal tumour suppressor genes associated with inherited high risk of breast and ovarian cancer. Genetic testing of BRCA1/2 will often reveal one or more sequence variants of uncertain clinical significance, some of which may affect normal splicing patterns and thereby disrupt gene function. mRNA analyses are therefore among the tests used to interpret the clinical significance of some genetic variants. However, these could be confounded by the appearance of naturally occurring alternative transcripts unrelated to germline sequence variation or defects in gene function. To understand which novel splicing events are associated with splicing mutations and which are part of the normal BRCA2 splicing repertoire, a study was undertaken by members of the Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA) consortium to characterise the spectrum of naturally occurring BRCA2 mRNA alternate-splicing events.

Methods mRNA was prepared from several blood and breast tissue-derived cells and cell lines by contributing ENIGMA laboratories. cDNA representing BRCA2 alternate splice sites was amplified and visualised using capillary or agarose gel electrophoresis, followed by sequencing.

Results We demonstrate the existence of 24 different BRCA2 mRNA alternate-splicing events in lymphoblastoid cell lines and both breast cancer and non-cancerous breast cell lines.

Conclusions These naturally occurring alternate-splicing events contribute to the array of cDNA fragments that may be seen in assays for mutation-associated splicing defects. Caution must be observed in assigning alternate-splicing events to potential splicing mutations.

  • BRCA2
  • breast cancer
  • tumor suppressor
  • alternate splicing

Statistics from Altmetric.com

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.