DNA Molecular Combing

DNA Molecular combing is a fiber spreading technique that was discovered in 1994 in the Ecole Nationale Supérieure de Paris (ENS) and developed by A. Bensimon at the Pasteur Institute. Patents are co-owned by CNRS and Pasteur Institute, while biomedical applications have been licensed to a company called Genomic Vision.

The DNA Combing technique generates glass coverslips covered with long parallel DNA fragments (up to 2 Mb). These individual DNA molecules can then be analysed by classical optical microscopic methods and fluorescent dyes, for physical mapping or DNA replication studies (as shown here).

The Operational Head of the platform is Marjorie Drac (CNRS IE) and its Scientific Head is Etienne Schwob (CNRS DR).

The Montpellier DNA Combing Facility offers three types of services:
  • Production, quality control and distribution of silanized coverslips (Marjorie Drac, chemistry). Due to intellectual property rights, this service is currently accessible only to CNRS labs. The users agree to collectively contribute to the running costs of this service.
  • Teaching: practical courses are organized on a regular basis and students or post-docs can be hosted in the lab for gaining access to the technology, from surface silanization to DNA combing and image analysis. Contact us for more information.
  • Automated image analysis: the facility has developed software for the automatic and rigorous analysis of spread DNA fibers (Thierry Gostan, bioinformatics). The Facility offers this analysis as a service on a pay-per-image basis. In the near future, the software will be made available directly to the user.

DNA fiber image analysis using the proprietary IDeFIx software • Automatic DNA fiber identification • Fiber length & track length measurements • Fiber position & track position measurements

This information can then be used to derive salient features of chromosome replication dynamics (fork velocity, fork pausing, inter-origin distance …) or to study chromosomal rearrangements (microdeletions, amplifications…), with a better precision and reproducibility than if done manually.


Ordering procedure:
  1. Choose the desired image package and send/fax your Order form to the address above. An invoice for payment is returned. Your account is then credited with the corresponding number of images (validity 1 year).
  2. Get in touch by mail with Thierry Gostan ( to decide on the best way to transfer your image files (tiff format, anonymous) and how the analysis needs to be done.
  3. Once the images have been analyzed, the annotated images and Excel result sheets will be sent back to you. At the same time, you will be noticed of the image credit remaining on your account.



1919 route de Mende
34293 Montpellier
Cedex 5