**New Molecular Diagnosis Approaches — From the Identification of Mutations to their Characterization**

Anne Bergougnoux, Magali Taulan-Cadars, Mireille Claustres and Caroline Raynal

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/60679

### **Abstract**

Molecular diagnosis of cystic fibrosis is based on the detection of mutation in the *CFTR* gene, identified in 1989. During the past 20 years, thanks to evolutions of diagnostic techniques, our knowledge of mutation spectrum and pathophysiological mecha‐ nisms involved in the disease has significantly improved. Sanger sequencing and quantitative methods greatly contributed to the identification of the 2,000 sequence variations reported worldwide in *CFTR*. We are now entering the new technological age with the generalisation of Next Generation Sequencing (NGS) technologies in diagnostics laboratories. These high throughput approaches allow scanning for the entire *CFTR* locus, including deep intronic regions, and in parallel other candidate genes that possibly influence the clinical evolution of patients. However, this powerful technology poses new challenge in test interpretation. In this chapter, we review the current and new technologies used in molecular diagnostics of cystic fibrosis, particularly NGS approaches. We also present current and new bioinformatics tools available for the interpretation of variants and *in vitro/ex vivo* and *in vivo* techniques that can be used to improve the characterization of the functional impact of *CFTR* variations.

**Keywords:** Next generation sequencing, *CFTR*, sequence variations, interpretation, functional characterization

© 2015 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
