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ModerateGeneral / metabolicUnknown

Aneuploidy, trisomy, sex chromosome XXY(XXY)

Klinefelter syndrome · Canine Klinefelter syndrome · XXY syndrome · Sex chromosome aneuploidy · Trisomy XXY

What it is

This is a genetic condition where a male dog is born with an extra sex chromosome, resulting in an XXY genetic makeup instead of the normal XY. This chromosomal abnormality primarily affects the reproductive system, preventing the normal development of the testicles. Because of this genetic difference, affected male dogs are unable to produce viable sperm.

How it presents

Owners typically notice this condition in young adulthood, most commonly when breeding attempts fail due to infertility. Affected male dogs may have abnormally small testicles and can sometimes exhibit a more feminine physical appearance or altered behavior.

Treatment

The underlying genetic defect cannot be cured, but the condition is easily managed with a one-time neutering surgery to prevent health complications in the underdeveloped testicles. The total cost for diagnostic karyotyping and surgery typically ranges from 300 to 1200 EUR.

How it's tested

No established test is currently catalogued for this condition.

Affected breeds

This condition isn't tied to a specific breed in our database.

Treatment cost

€300 – €1,200

Estimated range of typical treatment cost. Actual cost depends on severity, clinic and region.

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