Introduction to the DSRA
DSRA (Dento-skeletal-retinal Anomaly) is a hereditary disease that exclusively affects the Italian Cane Corso breed. This disease manifests itself through a series of abnormalities in the development and growth of the animal’s skeleton and teeth. Specifically, dogs with DSRA exhibit dwarfism and bone deformities, as well as extremely brittle, thin, transparent or discolored teeth.
In addition, DSRA is associated with progressive retinal degeneration leading to loss of vision in the dog.
The genetic cause of DSRA
The cause of this Dento-skeletal-retinal Anomaly DSRA lies in a mutation in the MIA3 gene, which is responsible for encoding the transmembrane protein MIA SH3. This protein plays a key role in the export of collagen and other proteins essential for proper growth and development in the body. This splicing defect in the MIA3 gene causes an almost complete loss of the function just mentioned. In more detail, the variant identified as XM_005640835.3:c.3822+3_3822+4del results in the skipping of two exons in the wild-type transcript, within a critical range of 5.8 Mb.
Genetic diagnosis and testing
To diagnose DSRA, a genetic test can be performed that reveals the animal’s genotype. This tool is particularly useful for breeders, as it helps to prevent unintentional breeding of puppies with this disease.
Inheritance and responsible reproduction
DSRA is characterized by an autosomal recessive inheritance pattern. This means that an individual will develop the disease only if he or she inherits the mutant allele from both parents (homozygous recessive). A heterozygous individual, on the other hand, has inherited the mutant allele from only one of the parents and, while not manifesting any symptoms, is clinically healthy. However, a heterozygous individual may transmit the mutant allele to his offspring. In the event that two heterozygous individuals are mated, their offspring will be distributed in this way: 25% will be healthy, 50% will carry the mutant allele (heterozygous), and 25% will inherit the mutant allele from both parents, thus developing the disease. This, by virtue of the above, unfortunately contributes to the spread of DSRA within the Cane Corso breed.
Prevention and breeding strategies
In conclusion, knowledge of DSRA and its genetic mechanisms is of fundamental importance to Italian Cane Corso breeders. Thanks to genetic testing, it is possible to identify carriers of the mutant allele and prevent the breeding of puppies affected by this hereditary disease, thus preserving the welfare and health of this fascinating dog breed.
Insights, Resources and Useful Links
- “Dental Skeletal Retinal Anomaly (DSRA)” from OFA – Orthopedic Foundation for Animals: https://ofa.org/dental-skeletal-retinal-anomaly-dsra/