Incontinentia pigmenti / IP (IKBKG-related) - Horse

What does this test analyse?

This genetic test analyses the IKBKG c.202C>T variant in horses. The condition is known as incontinentia pigmenti, IP, pigmentary mosaicism and an X-linked disorder of skin and pigment development.

What does it mean for the horse?

IKBKG has a role in cell survival and inflammatory signalling during development. In mares with one copy, the variant causes characteristic pigment and skin changes, often in a mosaic or streaked pattern. Visibility and extent can vary between animals.

For male foals, the variant is especially important: a male conceptus with the variant is expected not to be viable. This makes the test useful for breeding plans, interpretation of unusual colour or skin patterns and risk assessment in lines where IP occurs.

Practical value of this test

• Detects the known IKBKG c.202C>T variant.
• Helps distinguish IP from ordinary coat-colour variation.
• Supports breeding decisions in mares or lines with pigmentary mosaicism.
• Clarifies why male offspring with the variant are not expected.

Inheritance and result

IP is inherited as X-linked incomplete dominant. Heterozygous mares can show the visible IP phenotype. Male animals with the variant and female animals with two copies are considered not, or hardly, viable.