Primary Ciliary Dyskinesia (PCD) in Dogs
Primary Ciliary Dyskinesia (PCD) belongs to a genetically heterogeneous group of inherited ciliopathies. It causes impaired movement of motile cilia—microscopic hair-like structures lining the respiratory tract and other organs. When these cilia fail to function properly, mucus clearance becomes ineffective, leading to chronic inflammation and infection, particularly in the respiratory system.
Note: Since different variants are found in different breeds, please note that we will only perform the variant that is relevant to the breed of the tested dog. For example, if the breed is Old English Sheepdog, we will only test for the PCD variant in the CCDC39 gene.
Primary Ciliary Dyskinesia – Nova Scotia Duck Tolling Retriever
Primary Ciliary Dyskinesia (PCD) in Nova Scotia Duck Tolling Retrievers is a hereditary disorder caused by a breed-specific missense mutation that disrupts ciliary function. This leads to chronic respiratory infections, nasal discharge, and bronchitis. Affected dogs may also suffer from middle ear infections, reduced fertility due to impaired sperm motility, and in some cases, situs inversus—a mirror-image arrangement of internal organs.
PCD is inherited in an autosomal recessive manner, meaning dogs must inherit two copies of the faulty variant to show clinical signs. Genetic testing tailored to this breed is available and strongly recommended for breeding programs. While there is no cure, supportive care—including antibiotics, physiotherapy, and regular monitoring—can help manage symptoms and improve quality of life.
Primary Ciliary Dyskinesia – Eurasian
In Eurasiers, a genetic variant in the ZMYND10 gene has been linked to PCD. Affected puppies often show respiratory symptoms early in life, including unusual nasal discharge and shortness of breath (tachypnea, dyspnea). Some dogs also present with situs inversus, suggesting Kartagener’s syndrome.
However, not all Eurasiers with suspected PCD carry this variant, indicating that additional, as-yet-unidentified genetic causes may exist within the breed.
Primary Ciliary Dyskinesia – Alaskan Malamute
In Alaskan Malamutes, a variant in the NME5 gene causes recurrent respiratory tract infections, including runny nose and severe coughing. Fertility may be reduced due to impaired ciliary function in the reproductive tract. In some cases, affected dogs may also develop hydrocephalus.
Primary Ciliary Dyskinesia – Old English Sheepdog
PCD in Old English Sheepdogs is associated with a variant in the CCDC39 gene. Affected dogs experience frequent respiratory infections and reduced fertility. Approximately 50% of cases also present with situs inversus, consistent with Kartagener syndrome.
Primary Ciliary Dyskinesia – Australian Shepherd & Miniature American Shepherd
In these breeds, a variant in the STK36 gene has been linked to PCD. Symptoms typically appear within weeks of birth and include recurrent rhinitis, sneezing, and yellow-green nasal discharge. While antibiotics offer temporary relief, symptoms often recur once treatment ends.
