These new innovative products allow the rapid detection of the presence or absence of a deletion in the Dystrophin gene, and the simple and easy assessment of female carrier status
Cytocell Technologies has launched the new Chromoprobe Multiprobe-DMD system and a range of Dystrophin Exon specific probes.
Deletions in the Dystrophin gene are known causes of Duchenne Muscular Dystophy (DMD) and Becker Muscular Dystrophy (BMD).
DMD and BMD are X-linked recessive neuromuscular diseases caused by mutations in the Dystrophin gene.
DMD is a rapid progressive form of muscular dystrophy and affects 1/3500 newborn males whereas BMD has a slower progressive nature and affects 1/30,000 newborn males.
The Dystrophin gene maps to Xp21 and spans 79 exons.
Approximately 65% of mutations of the gene are large deletions which are not evenly distributed but are concentrated in hot-spots, one towards the 5' part of the gene which encompasses exons 3-7 and another in the central portion of the gene, encompassing exons 43-51.
Mothers of affected males have a two-thirds chance of carrying a Dystrophin mutation.
Given the X-linked recessive pattern of inheritance, the recurrence risk for the disease is extremely high, making carrier detection very important.
The fluorescence in situ hybridisation (Fish) method utilised by Cytocell's Chromoprobe Multiprobe system 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.
Several international groups have confirmed the use of Fish for carrier detection as an effective and reliable alternative to molecular techniques De novo deletions account for about 30% of all DMD/BMD cases so the recurrence risk for these are lessened.
However, studies have shown that some mothers are in fact gonadal mosaics (where the mosaicism is restricted to the gonads) and are presumed to carry a Dystrophin deletion in a proportion of their gametes.
This new Fish test can be used to screen future pregnancies for deletions and provide testing for male offspring in such cases.
The Chromoprobe Multiprobe-DMD system allows the simultaneous analysis of different exons of the Dystrophin gene whose deletion leads to either DMD or BMD.
The Chromoprobe Multiprobe technology combined with this set of Dystrophin exon-specific Fish probes 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.
Commenting on the launch of the new products, Cytocell's managing director Martin Lawrie said: "The launch of the new Chromoprobe Multiprobe-DMD system and the new range of Dystrophin Exon specific probes are exciting additions to Cytocell Technologies product portfolio.
"We are continuing to use our extensive knowledge and experience in developing new innovative screening solutions for the detection of chromosome abnormalities in clinical and research laboratories worldwide"
