Copper toxicosis / Wilson disease (COMMD1-related) - Bedlington Terrier

What does this test assess?

This genetic test analyses the COMMD1 exon 2 deletion variant in Bedlington Terrier. The disorder and risk profile are described as copper toxicosis, copper storage disease, copper accumulation, copper-associated hepatopathy and copper-associated chronic hepatitis. In the Bedlington Terrier, the COMMD1 exon 2 deletion causes an autosomal recessive form of copper toxicosis. COMMD1 was formerly called MURR1 and is involved in normal hepatic copper handling.

What does this condition mean?

Copper is required for normal metabolism, but excess copper in the liver damages liver cells. Dogs with copper toxicosis can appear normal for a long time and later develop increased liver enzymes, poor appetite, vomiting, lethargy, weight loss, jaundice, behavioural change, chronic hepatitis or liver cirrhosis. Diet, other genetic factors and breed background all influence how strongly the genotype is expressed.

Inheritance and result

COMMD1-related copper toxicosis is inherited as an autosomal recessive condition. Dogs with two copies of the exon 2 deletion develop this inherited form of copper toxicosis; carriers are usually healthy but can pass the variant on.

• Clear: the tested variant was not detected.
• Carrier/modifier: one copy of the variant was detected and is relevant for breeding or risk assessment.
• Two copies/highest variant dose: the variant is present twice, or for X-linked ATP7A present on the single X chromosome of a male.

Practical value of this test

This DNA test is practically useful because copper accumulation often becomes visible only late. An early genetic result helps breeders avoid risk matings, helps owners understand which dogs deserve extra attention and supports more targeted follow-up when liver values or family history make that relevant.

• Helps plan matings and identify dogs with relevant risk information.
• Enables combined interpretation with other copper metabolism tests.
• Provides concrete information for breed-focused selection and liver-health follow-up.