Persistent Müllerian duct syndrome / PMDS (AMHR2-related) - Dog

What does this test examine?

This genetic test analyses the AMHR2 c.262C>T variant for Persistent Müllerian duct syndrome, also known as PMDS or AMHR2-related PMDS. AMHR2 encodes the receptor needed during male embryonic development for regression of the Müllerian ducts. When this signalling pathway fails, genetically male dogs can retain uterus-like tissue or other female-derived reproductive structures alongside male reproductive organs.

What does PMDS mean for the dog?

PMDS matters because affected males often look externally normal. Some males are cryptorchid, while others may only be noticed later through fertility questions, reproductive abnormalities or complications caused by retained Müllerian structures. The condition can be linked with cryptorchidism, problems in retained testes and inflammation of uterus-like tissue.

Inheritance and result

The trait is autosomal recessive and sex-limited. Males with two copies of the variant develop the PMDS genotype. Dogs with one copy are carriers and can pass the variant on without showing the condition. Females do not show the PMDS phenotype, but they can transmit the variant to offspring.

• Clear: the tested variant was not detected.
• Carrier: one copy is present and can be passed to offspring.
• Affected genotype: two copies are present; in genetically male dogs this causes PMDS.

Practical value of this test

The test is useful for breeders because carriers and externally normal dogs are difficult to recognise without DNA testing. The result helps avoid high-risk matings, plan litters more deliberately and manage lines with Schnauzer background responsibly. For veterinarians and owners, it provides genetic clarity when a male dog shows cryptorchidism, reproductive abnormalities or unexpected internal female structures.