Hypotrichosis / HY (KRT71-related) - Cattle

Hypotrichosis (HY) in Hereford cattle

This DNA test examines the KRT71 variant c.281_288del that causes congenital hypotrichosis, also known as HY, in Hereford cattle. Hypotrichosis means clearly reduced hair growth. Affected calves may be born hairless or nearly hairless and usually develop a very short, fine, woolly, rough or curly coat.

What does this trait mean?

• Appearance: abnormal hair growth is often most visible on the ears, inner limbs and thoracic-abdominal region.
• Genetic cause: KRT71 encodes a keratin important for hair follicle and hair shaft structure.
• Inheritance: HY is inherited as an autosomal recessive trait; carriers are usually normally coated but can pass the variant on.

Practical value of this test

The result helps breeders distinguish clear animals, carriers and genetically affected animals. This supports avoidance of carrier pairings, management of the variant in the breeding population and confirmation of the hereditary cause of abnormal hair growth in Hereford cattle.