Chromoprobe Multiprobe® - DMD System

Duchenne Muscular Dystrophy (DMD) and Becker Muscular Dystrophy (BMD) are X-linked recessive neuromuscular diseases caused by mutations in the Dystrophin gene. Approximately 65% of mutations of the gene are large deletions, which are not evenly distributed but are concentrated in "hot-spots". Given the X-linked recessive pattern of inheritance, the recurrence risk for the disease is extremely high, making carrier detection very important. Thus, studies have shown that some mothers are gonadal mosaics and are presumed to carry a Dystrophin deletion in a proportion of their gametes.

The Chromoprobe Multiprobe-DMD System combines the Chromoprobe Multiprobe, technology with a set of Dystrophin exon-specific FISH probes to allow the simultaneous analysis of different exons of the Dystrophin gene. It provides an alternative approach to molecular methods currently used to identify Dystrophin gene deletions in female relatives of diagnosed affected males and to identify Dystrophin gene deletions in clinically affected but not yet diagnosed males.

The Chromoprobe Multiprobe-DMD System has been developed by Cytocell using a published set of probes directed against the most commonly deleted exons of the Dystrophin gene. The glass 24 square Multiprobe device contains 21 exon-specific probes which cover the deletion "hot spots" of the Dystrophin gene. Each probe contains one or more exons and is approximately 40 Kb. The exons are accompanied by an X chromosome a-satellite probe to provide an internal hybridisation control and effective chromosome identification.

Test and control probes are differentially labelled: the Dystrophin probes are labelled with a red fluorophore (Texas Red spectrum) whilst the a-satellite probes are either labelled with a green or a blue fluorophore (FITC or Coumarin spectrum).

In addition, probes for the DAX-1 gene, responsible for Adrenal Hypoplasia Congenita (AHC), and the Glycerol Kinase gene (GK) are also included on the Multiprobe device. These two genes have been associated with the contiguous gene deletion recognised as Complex Glycerol Kinase Deficiency (GKD) with DMD.

The FISH method provides an alternative approach to current molecular methods for carrier detection. Both methods are directed at exon-specific hot spots of the Dystrophin gene, which are responsible for the majority of deletions. However, unlike molecular genetic methods, because FISH on metaphase chromosomes allows both X chromosomes to be analysed directly, identification of carriers then does not depend on dosage assessment.

The Chromoprobe Multiprobe System is designed for fluorescence in situ hybridisation of metaphase chromosomes and interphase nuclei from cultured peripheral blood cells.

These products are not available in the USA.

Related Products

Aquarius Dystrophin Exon Specific Probe Range

All the probes supplied on the Chromoprobe Multiprobe-DMD device are also available individually as Aquarius® Dystrophin Exon Specific probes.

Each probe contains the Dystrophin exon specific probe or gene probe and the a-satellite for the X chromosome control probe labelled in a different colour, which serves as a confirmatory probe for the identification of the chromosome of interest. The kits are supplied in an economical 5 test format and come complete with DAPI counterstain.

These products are not available in the USA.