Congenital Hypothyroidism with Goiter Spanish Water Dog Type (CHG-SWD)
Congenital Hypothyroidism, CHG
Congenital Hypothyroidism with Goiter in Spanish Water Dogs (CHG-SWD) is a hereditary condition that leads to an enzyme deficit that is important for the production of thyroid hormone. Lack of this hormone leads to abnormal development and metabolism. Typically, clinical signs are noticeable around 2 weeks of age with affected dogs exhibiting reduced body size and movement when compared to other littermates. Additional signs of the disease may include growth retardation (dwarfism), delayed developmental milestones such as eye opening and tooth eruption, abnormal skin and hair texture, and unresponsiveness. Congenital hypothyroidism in this breed often presents with a swelling in the neck (goiter) that results from an enlarged thyroid gland. The condition typically progresses to failure to thrive with affected puppies not surviving more than a few months.
Reading Your Results
These dogs have two copies of the normal gene and will neither develop Congenital Hypothyroidism nor pass this mutation to their offspring.
B. (CARRIER/NOT AFFECTED):
These dogs have one copy of the normal gene and one copy of the mutation associated with this disease. They will not develop Congenital Hypothyroidism but 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 and are likely to develop Congenital Hypothyroidism with Goiter.
773950-773951: 1 bp insertion (ins G)
Fyfe JC, Lynch M, Olsen J, Louёr E. A thyroid peroxidase (TPO) mutation in dogs reveals a canid-specific gene structure. Mamm Genome. 2013 Apr;24(3-4):127-33. Epub 2012 Dec 8. [Pubmed: 23223904]