The following provides an explanation of genetic disease and descriptions of those diseases prevalent in boxers.

Genetically inheritable diseases prevalent in boxers

• Aortic stenosis/sub-aortic stenosis (AS/SAS) is one of the most common heart defects occurring in boxers. Stenosis is narrowing of the aorta, right below the aortic valve, which forces the heart to work harder to supply blood. Reduced blood flow can result in fainting and even sudden death. The disease is inherited but its mode of transmission is not known at this time. Diagnosis must be made by a veterinary cardiologist, after detection of a heart murmur. Breeding dogs must be properly screened for this disease and affected dogs must not be bred from.

• Boxer cardiomyopathy is an electrical conduction disorder which causes the heart to beat erratically (to have an arrhythmia) some of the time and can result in weakness, collapse or sudden death. These arrhythmias are difficult to detect with any certainty by listening to the heart with a stethoscope, unless they are very frequent thus the first sign of the disease may be fatal. Cardiomyopathy is a genetically inheritable condition with devastating results. Because a dog cannot be cleared of cardiomyopathy by a routine veterinary examination and the disease may not show itself until after a dog reaches breeding age, it is important that all breeding stock are properly screened for this disease.

Boxer cardiomyopathy is a distinct disease from the dilated cardiomyopathy common in some other breeds. Other names for BCM are Boxer Arrythmic Cardiomyopathy (BAC), Familial Ventricular Arrhythmia (FVA) and Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC). 

• Hip dysplasia is an inheritable malformation of the hip joint leading to osteoarthritis. The hip joint is a ball and socket joint, where the top of the thigh bone (femur) fits into a socket in the pelvis. The bones are held in place by ligaments. Hip dysplasia occurs when the socket is poorly formed or the ligaments are loose, enabling the ball of the femur to subluxate – to slide part way out of its socket. Over time this causes degeneration of the joint (osteoarthritis) and the dog suffers pain and becomes weak and lame in the hind end. Hip dysplasia is a progressive disease, meaning that it becomes worse with time.

Hip dysplasia has polygenic inheritance, meaning it is caused by the inheritance of multiple genes. It is not yet known how many, or which genes are involved. Factors that can make the disease worse include excess weight, excess or prolonged exercise before maturity, a fast growth rate, and high-calorie or supplemented diets.

Hypothyroidism describes an inactive thyroid gland which can be responsible for such conditions as epilepsy, alopecia or hair loss, obesity, lethargy, hyperpigmentation, pyoderma and other skin conditions. While not considered life threatening, the quality of life for a dog suffering from hypothyroidism is much reduced.