Dilated Cardiomyopathy (DCM) causes the heart to dilate to improve output which prevents heart muscle cells from contracting normally.  The dilation seen during disease progression leads to increased pressure within the heart and eventual heart failure.  Almost half of dogs diagnosed with this disease do not survive beyond a few months.  Although testing for the DCM1 mutation can be used as a guide for diagnosing the disease, it is recommended to use echocardiogram testing at 1 – 2 years along with a baseline Holter monitor test to confirm disease presence and progression.  It is also recommended that dogs in breeding programs be physically tested every six months to determine disease status.

It is important to note that the DCM1 mutation is autosomal dominant with variable penetrance which means that only one copy of the mutated gene is necessary to cause DCM but due to its variable penetrance some positive dogs may never develop signs of the disease. It is also important to note that there are at least two genetic mutations responsible for DCM in the Doberman.

• Doberman Pinscher

A (CLEAR/NORMAL): These dogs have two copies of the normal gene and will neither develop DCM due to the DCM1 mutation nor pass this mutation to their offspring.

B (CARRIER/AFFECTED): These dogs have one copy of the normal gene and one copy of the mutation associated with this disease. They can develop DCM and will, if bred, pass the mutation to 50% of its offspring, on average.

C (AT RISK/AFFECTED): These dogs have two copies of the mutation associated with this disease which can result in heart dilation and eventual heart failure.