Breeds Affected: Norfolk Terriers, Cairn Terriers

Samples Accepted: Blood, Buccal Swabs

Disease Information: Asymptomatic macrothrombocytopenia (AM) is a disorder of platelet formation.

Inheritance Information: Asymptomatic Macrothrombocytopenia is autosomal recessive, meaning that animals with two copies of this allele will be affected. Animals with one copy of the gene will be clinically-normal carriers.

The possible genotypes are:

N/N The dog is normal, and cannot produce affected offspring.

N/am The dog is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/am carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.

am/am The dog is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/am carrier, 50% of the offspring will be carriers and 50% will be affected.

Recommendations:

– Carriers may be bred to normal animals (N/am x N/N) without any risk of producing affected offspring. The offspring should be tested before breeding to determine if they are carriers or normal.

– Breeding two carriers (N/am x N/am) is not recommended due to the possibility of 25% of the offspring being affected.

– Affected animals (am/am) should not be used for breeding.

Test Information: This mutation test identifies a single base pair change in exon 1 of the TUBB1 gene.

Gelain, M.E., Tutino, G.F., Pogliani, E., Bertazzolo, W.: Macrothrombocytopenia in a group of related Norfolk terriers. Vet Rec 167:493-4, 2010. Pubmed reference: 20871084. Doi: 10.1136/vr.c4782.

Further information is available at the Online Mendelian Inheritance in Animals website.

Test #: D102
Cost: 35 € (excl. VAT)
Time: 7-10 days