Dilated cardiomyopathy is an inherited heart disease affecting the Doberman breed. The disease is characterised by dilation of the ventricles leading to progressive thinning of the wall and irregular heartbeat as well as enlargement of the ventricle, which decrease the overall heart function and output. Insufficient blood circulation can lead to build up of fluid in the lungs and other parts of the body. Affected dogs can show progressive deterioration leading to death or can be relatively asymptomatic and then die suddenly.
Dilated cardiomyopathy is a widespread inheritable disease in Doberman. Affected dogs suffer from congestive heart failure or sudden cardiac death. Ventricular tachyarrhythmia is a typical sign of DCM and can be diagnosed by an echocardiogram or electrocardiogram (ECG). Pedigree analysis indicates an autosomal dominant mode of inheritance. Two genetic variants have been identified to be associated with dilated cardiomyopathy: the DCM1 variant located in the PDK4 gene (provides energy to the heart) and the DCM2 variant located in the titin (TITIN) gene (This listing) (helps the heart to contract). We also offer a bundle of both tests Bundle: DCM1 + DCM2
The mode of Inheritance in Doberman is dominant with variable penetrance, which means that genetically affected dogs may also show very mild or even no symptoms during their lifetime. In addition to the genetic factor, other factors including nutrition, exercise level and other genes can contribute towards increasing the risk of developing the disease. And therefore, the genetic test helps to identify the DCM variants, however, a proportion of genetically affected dogs may not develop the disease or show any of its symptoms. Moreover, there maybe other, yet unidentified, variants which can cause DCM in this breed and so even if a dog is tested clear for both variants, regular clinical testing at the vet is still recommended.
- Dogs carrying the DCM1 variant (alone) heterozygous or homozygous, are 10 times more likely to develop the disease than dogs without the variant, 37% of the dogs with this variant will develop the disease.
- Dogs carrying the DCM2 variant are 21 times more likely to develop the disease, 50% of the dogs with this variant will develop the disease.
- Dogs carrying both variants have the highest risk to develop DCM (30 times) and 60% of the dogs with both variants show symptoms. These dogs should be monitored regularly for signs of the disease so that medication could be provided if needed to slow down the progression of DCM.
The genetic test should help to reduce the frequency of the known variants in the breed without reducing the gene pool. Therefore, heterozygous dogs carrying only one variant (DCM1 or DCM2) should not be excluded from breeding, especially if there is no familial history of heart problems, but should be bred with dogs that are tested free for both variants.