Precision medicine identifies a pathogenic variant of the ITGA2B gene responsible for Glanzmann's thrombasthenia in a

Ronald H L Li1, Eric Ontiveros2, Nghi Nguyen1

  • 1Department of Veterinary Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, Davis, California, USA.

Insights

A novel genetic variant in the ITGA2B gene caused a severe bleeding disorder in a cat. This condition, similar to Glanzmann's thrombasthenia, was identified using whole genome sequencing.

Area of Science:

  • Veterinary Genetics
  • Comparative Genomics
  • Hemostasis Research

Background:

  • A nonpedigreed male cat presented with severe bleeding episodes, including epistaxis and bladder hemorrhage.
  • The cat experienced urethral obstruction secondary to hemorrhage following cystocentesis.

Observation:

  • The cat exhibited impaired platelet aggregation in response to adenosine diphosphate (ADP) and arachidonic acid (AA).
  • Flow cytometry and western blot analyses revealed an absence of surface and total expression of the integrin αIIbβ3.

Findings:

  • Whole genome sequencing identified a homozygous frameshift variant (c.1986delC) in the ITGA2B gene.
  • This variant, p.Pro662fs (ITGA2B P662X), leads to premature protein termination and is predicted to affect β3 unit expression.

Implications:

  • A novel ITGA2B gene variant associated with a bleeding diathesis was identified in a domestic cat.
  • The identified phenotype and genetic defect closely mimic Glanzmann's thrombasthenia, a condition previously unreported in felines.
  • This study highlights the utility of whole genome sequencing for precision medicine in veterinary diagnostics.
Abstract