The thyroid gland is located in the neck and produces hormones that help regulate the body's energy use, growth, and organ function. In dogs with CHG, genetic mutations interfere with the normal synthesis or release of thyroid hormones. As the body attempts to compensate for the hormone deficiency, the thyroid gland may enlarge, resulting in a visible or palpable goitre. The lack of adequate thyroid hormone during early development can have significant effects on both physical and mental growth.
Clinical signs of Congenital Hypothyroidism with Goitre typically become apparent during puppyhood. Affected puppies may exhibit poor growth, delayed development, lethargy, weakness, mental dullness, disproportionate body size, shortened limbs, and abnormalities in skeletal development. Other signs can include a thickened facial appearance, delayed tooth eruption, poor coat quality, and reduced activity levels. In severe cases, untreated dogs may experience permanent developmental impairment and reduced quality of life.
The CHG DNA Health Test is designed to identify the specific genetic mutation associated with this inherited thyroid disorder. Testing is simple and non-invasive, usually requiring a cheek swab or blood sample. The collected sample is analyzed in a specialized laboratory to determine whether the dog carries the mutation responsible for CHG. Since DNA remains constant throughout life, testing can be performed at any age, including in puppies before clinical signs become evident.
Results are generally reported in one of three categories:
- Clear (Normal): The dog does not carry the CHG mutation and cannot pass it to offspring.
- Carrier: The dog carries one copy of the mutation but is typically healthy and unaffected. However, it can pass the mutation to future generations.
- Affected/At Risk: The dog carries two copies of the mutation and has a significantly increased likelihood of developing Congenital Hypothyroidism with Goitre.
Genetic testing for CHG provides valuable information for breeders, veterinarians, and dog owners. Breeders can use test results to make informed breeding decisions that help reduce the prevalence of the disorder while maintaining genetic diversity within the breed. Avoiding the mating of two carrier dogs significantly decreases the risk of producing affected puppies.
For dog owners, knowing a dog's genetic status allows for early veterinary monitoring and timely intervention. Dogs diagnosed with hypothyroidism may benefit from hormone replacement therapy and ongoing medical management, which can greatly improve health outcomes when treatment begins early. Regular veterinary examinations can help monitor growth, development, and thyroid function.
The Congenital Hypothyroidism with Goitre (CHG) Health Test is a reliable genetic screening tool that supports responsible breeding practices, promotes canine endocrine health, and helps reduce the impact of this inherited disorder in future generations. Through early detection and informed breeding decisions, breeders and owners can contribute to healthier dogs and improved long-term welfare.
