Congenital Dyshormonogenic Hypothyroidism with Goiter (Shih Tzu Type)

General Information: Congenital Dyshormonogenic Hypothyroidism with Goiter (Shih Tzu Type) is an inherited disorder in dogs characterized by the impaired synthesis of thyroid hormones due to a defect in thyroid hormone production. This condition leads to an enlarged thyroid gland (goiter) and a deficiency in thyroid hormones, which are essential for normal growth, metabolism, and development. Affected dogs typically exhibit symptoms such as stunted growth, lethargy, mental dullness, constipation, dry skin, hair loss, and cold intolerance. The condition is present at birth (congenital) and results from mutations in genes involved in thyroid hormone biosynthesis. Without appropriate thyroid hormone replacement therapy, affected dogs may suffer from severe growth retardation and developmental abnormalities.

How to Read Your Dog's Test Results for this Genetic Variant:

Two Variants Detected: Dog Likely Affected

One Variant Detected: Dog Unlikely Affected

No Variants Detected: No Effect

Gene / Testing Information: Genetic testing for Congenital Dyshormonogenic Hypothyroidism with Goiter (Shih Tzu Type) can identify carriers of the gene mutation responsible for this condition. The disorder is inherited in an Autosomal Recessive manner, meaning that a dog must inherit two copies of the mutated gene, one from each parent, to be affected by the disease. Dogs with only one copy of the mutation (carriers) typically do not show symptoms but can pass the mutated gene to their offspring. When two carrier dogs are bred, each puppy has a 25% chance of being affected by the disease, a 50% chance of being a carrier, and a 25% chance of being completely clear of the mutation. Reliable genetic testing is essential for responsible breeding practices to prevent the spread of this condition, and breeding two carriers together is not recommended to avoid producing affected puppies. Dogs that test negative for the mutation do not carry the gene and have no increased risk of producing affected offspring.