ACAN-dwarfism is found in Shetland ponies and miniature horses, in which abnormal cartilage growth leading to skeletal problems and dwarfism. Four different disease-causing variants of the ACAN gene are known so far: d1, d2, d3* and d4. The inheritance is autosomal recessive.

This test detects the mutation in the B4GALT7 gene that causes dwarfism in the Friesian horse. The inheritance is autosomal recessive.