Summary

Glanzman Thrombasthenia is an inherited bleeding disorder marked by a failure of platelet aggregation. Affected horses bleed excessively and show a lack of clotting. There is no effective treatment.

Date of Last Update: 08/02/2016

Results

Understanding the Results

Results of the genetic test for Glanzman Thrombasthenia are presented as shown below.

Disease Name and Genes

Two alleles of the gene encoding platelet glycoprotein IIb, Integrin, Alpha-2B (ITGA2B), are associated with Glanzman Thrombasthenia.

Glanzman Thrombasthenia results from a G to C substitution in exon 2 of ITGA2B that causes the replacement of an Arginine (R) with a Proline (P) at codon 72 (ITGA2B-R72P).

Glanzman Thrombasthenia also results from a 10 base-pair deletion that spans the splice site between exon 11 and intron 11 identified in a Quarter Horse. This mutation is predicted to result in a lack of splicing of intron 11 and inclusion of a termination codon 50 bp downstream of the deletion. Lack of expression of this mRNA is most likely the result of nonsense-mediated decay.

Inheritance

Glanzman Thrombasthenia resulting from mutations in the ITGA2B gene is inherited as a recessive trait. The recessive allele is here abbreviated as GT, with the dominant wild-type allele abbreviated as N.