How is Thrombopathia (Discovered in the Eskimo Spitz) inherited in dogs?

Thrombopathia (Discovered in the Eskimo Spitz) follows a Autosomal recessive inheritance pattern. It has been observed in 4 of 266 breeds screened in the Sniff Atlas.

What is the human equivalent of Thrombopathia (Discovered in the Eskimo Spitz)?

OMIA links Thrombopathia (Discovered in the Eskimo Spitz) to its human counterpart in OMIM (OMIM 615888), the bridge to the deeper human-medicine literature for the same underlying biology.

Canine Mendelian disease record

Thrombopathia (Discovered in the Eskimo Spitz)

Q: How well studied is Thrombopathia (Discovered in the Eskimo Spitz) in dogs?

OMIA curates 8 peer-reviewed references for Thrombopathia (Discovered in the Eskimo Spitz). The full, linked citation list is on this page.

Thrombopathia (Discovered in the Eskimo Spitz). Autosomal recessive. Observed in 4 of 266 breeds tested in the Sniff Atlas, with measured carrier frequencies drawn from 242,665 dogs (Donner 2023). Per-dog phenotype outcome depends on penetrance, modifiers, and environment; the carrier frequencies below describe variant prevalence, not disease incidence.

OMIA identifier: OMIA:002433-9615
Inheritance: Autosomal recessive
Source dataset: Sniff Atlas v1.0.1 / DOI

The human connection

A model of human platelet-type bleeding disorder 18

This is the canine counterpart of platelet-type bleeding disorder 18 in people. That makes affected dogs a naturally-occurring model of the human disease, and it is part of why studying dogs moves medicine forward for everyone. It does not mean your dog has the human disease. It means the two share an underlying biology.

In people, the disease is described as: Bleeding disorder due to CalDAG-GEFI deficiency is a rare hematologic disease due to defective platelet function and characterized by mucocutaneous bleeding starting in infancy (around 18 months of age), presenting with prolonged and severe epistaxis, hematomas and bleeding after tooth extraction. Massive menorrhagia and chronic anemia have also been reported.

In humans it is also called: BDPLT18, bleeding disorder due to CalDAG-GEFI deficiency, bleeding disorder, platelet-type, 18.

MONDO:0014386 OMIM 615888

Mapped from OMIA via the human disease's OMIM entry to the Mondo Disease Ontology (Monarch Initiative, CC-BY 4.0). Sniff renders this as a model-of link; the canine disease remains the subject of this page.

About this disease

From OMIA's curated record

Documented in OMIA (Online Mendelian Inheritance in Animals). This describes the disease as recorded in the published literature, not a prediction for any individual dog. As of 2026-06-03.

Summary

Boudreaux et al. (2007) reported likely causal variants in Calcium-Diacylglycerol Guanine Nucleotide Exchange Factor I (CalDAG-GEFI). Based on NCBI information the gene name was listed as RASGRP1 gene in OMIA. A recent BLAST search of the published data identified that the correct gene name is RASGRP2. Information from OMIA 001003-9615 'Thrombopathia in Canis lupus familiaris' was moved to this entry and variant table information was updated accordingly [22/01/2022].

Clinical features

Variants in the gene that encodes CalDAG-GEFI cause decreased fibrinogen receptor activation (Cortese et al., 2020) and severely impaired or absent platelet aggregation response to adenosine diphosphate, collagen, and platelet activating factor (Boudreaux et al., 2007). There is also a delayed but full response to thrombin (Boudreaux, 2012). The clot retraction assay is normal (Boudreaux, 2012), but the kinetics are impaired – the time to full aggregation is prolonged to 4-6min compared to 3min in unaffected dogs (Cortese et al., 2020). Clinically, affected dogs experience epistaxis, gingival bleeding and petechiation on mucous membranes and skin, and prolonged bleeding time (Boudreaux et al., 2007). Platelet counts and coagulation screening tests will have normal results (Boudreaux, 2012). Some affected Basset Hounds may present with weakness and rear limb paralysis secondary to spinal cord haemorrhage (Boudreaux, 2012). IT thanks DVM student Jovial Zheng, who provided the basis of this contribution in May 2023.

Molecular genetics

Boudreaux et al. (2007) reported this disorder in three breeds being due to three different mutations in the RASGRP2 gene that encodes Calcium-Diacylglycerol Guanine Nucleotide Exchange Factor I (CalDAG-GEFI): Eskimo Spitz dogs have frameshift mutation (452-453insA), Bassett Hounds have a three-base deletion (509-511delTCT), and Landseers have a nonsense mutation (982C>T).

Human analog

OMIA links this condition to its human counterpart in OMIM (Mendelian Inheritance in Man), the place to read across to the deeper human literature for the same biology.

Disease · OMIM 615888 Gene · OMIM 605577

Source: OMIA (Nicholas, Tammen & the Sydney Informatics Hub), entry OMIA:002433-9615, doi:10.25910/2AMR-PV70 (CC-BY 4.0).

Signs & cross-references

How it presents

Catalogued in the Mondo disease ontology (the cross-species disease identity used by the Monarch Initiative) as platelet-type bleeding disorder 18 (MONDO:0014386).

Phenotype terms: Human Phenotype Ontology + Mammalian Phenotype Ontology; disease terms: Mondo (Monarch Initiative). Cross-references curated by OMIA (doi:10.25910/2AMR-PV70, CC-BY 4.0).

The evidence

Published references

The peer-reviewed papers behind this disease, curated by OMIA. Starred entries are OMIA-designated landmark papers. Showing 6 of 8.

Platelet function and therapeutic applications in dogs: current status and future prospects. · Animals (Basel) · 2020 · PMID 31991713
Inherited platelet disorders. · J Vet Emerg Crit Care (San Antonio) · 2012 · PMID 22316339
Characteristics, diagnosis, and treatment of inherited platelet disorders in mammals. · J Am Vet Med Assoc · 2008 · PMID 18922051
Calcium-diacylglycerol guanine nucleotide exchange factor I gene mutations associated with loss of function in canine platelets. · Transl Res · 2007 · PMID 17656327
Identification of an intrinsic platelet function defect in Spitz dogs. · J Vet Intern Med · 1994 · PMID 8046682
Absent platelet aggregation with normal fibrinogen binding in Basset Hound hereditary thrombopathy. · Thromb Haemost · 1989 · PMID 2512673

References curated by OMIA (Nicholas, Tammen & the Sydney Informatics Hub), doi:10.25910/2AMR-PV70 (CC-BY 4.0). Full list at the OMIA entry.

Predict a litter

Set each parent's status for Thrombopathia (Discovered in the Eskimo Spitz) and see the odds for their puppies. Single recessive variant, exact Mendelian math.

Parent A

Parent B

NNClear

NmCarrier

mmAffected

Clear25%

Carrier50%

Affected25%

These are the genetic odds for one known variant, not a promise: a real litter varies around them, and penetrance or other genes can change whether the condition ever appears. Use it to avoid pairing two carriers and to keep a line healthy, not to engineer a dog. Inheritance mode per OMIA.

Your breed

See what Thrombopathia (Discovered in the Eskimo Spitz) looks like in your dog's breed.

Carrier frequency by breed

Top 4 well-sampled breeds (n ≥ 50)

Maximum carrier frequency per breed across variants in the Donner 2023 cohort, with Wilson 95% confidence intervals. The list below is split into well-sampled breeds (n ≥ 50 tested) and small-sample breeds (n < 50, where the Wilson CI typically spans more than 20 percentage points and frequencies should not be compared directly to the well-sampled entries). Frequencies are population-level, not per-litter or per-line.

0%3%5%

Basset Hound1.3% · n 990

1.3%n 990

American Eskimo Dog0.83% · n 302

0.83%n 302

Rottweiler<0.1% · n 4,718

<0.1%n 4,718

Pomeranian<0.1% · n 5,294

<0.1%n 5,294

n = 11,304 dogs · Donner et al. 2023 carrier-screening cohort · Sniff Atlas

Each bar is one well-sampled breed; the whisker is its Wilson 95% CI, and fainter bars have wider intervals. Frequencies are population-level, not per-litter. Carrier status for Thrombopathia (Discovered in the Eskimo Spitz) is measured; phenotype outcome depends on penetrance and modifiers.

▸ Full table with Wilson 95% confidence intervals

Breed	Carrier frequency	Wilson 95% CI	n tested
Basset Hound	1.3%	[0.8%, 2.2%]	990
American Eskimo Dog	0.83%	[0.3%, 2.6%]	302
Rottweiler	<0.1%	[0.0%, 0.1%]	4,718
Pomeranian	<0.1%	[0.0%, 0.1%]	5,294

262 additional breeds in the Donner 2023 cohort were tested but showed no carriers.

Scope of this record

This record carries the breed-level carrier frequencies from the Donner 2023 cohort. Penetrance data (the fraction of at-risk dogs that develop the phenotype) is not yet quantified for this disease in the Sniff Atlas v1.0.1. The OMIA entry is the authoritative reference for the clinical phenotype, inheritance pattern, and gene assignment.

Predicted disease relevance at the per-dog level is UNPROVEN. The carrier frequency is measured; phenotype outcome depends on penetrance, environment, and modifier loci. Consult a veterinarian for clinical interpretation.

How to cite this record

If you use this record in published work, cite the Sniff Atlas (the published dataset that carries the breed-level carrier frequencies) and the upstream sources:

Sniff Atlas v1.0.1 for the per-breed carrier frequencies:
Gehring, M. (2026). Sniff Atlas v1.0.1. Zenodo. https://doi.org/10.5281/zenodo.20566358. CC-BY 4.0.
OMIA for the disease definition, inheritance, and gene assignment:
Nicholas, F. W., & Tammen, I. (2024). OMIA. Sydney Informatics Hub, The University of Sydney. https://doi.org/10.25910/2AMR-PV70. Entry: OMIA:002433-9615.
Donner et al. 2023 for the breed × variant carrier-frequency cohort:
Donner, J., Freyer, J., Davison, S., Anderson, H., Blades, M., Honkanen, L., et al. (2023). Genetic prevalence and clinical relevance of canine Mendelian disease variants in over one million dogs. PLOS Genetics, 19(2), e1010651. https://doi.org/10.1371/journal.pgen.1010651.

Full citation formats (BibTeX, RIS, CITATION.cff) at sniff.world/cite.

Sniff Atlas v1.0.1, the source dataset for these frequencies.
Browse breeds, per-breed Mendelian profiles, including this disease in context.
OMIA entry OMIA:002433-9615, authoritative clinical reference.
About OMIA, the catalogue this record comes from, and how Sniff uses it.

Last updated June 20, 2026

Sources: Sniff Atlas v1.0.1 · OMIA OMIA:002433-9615 · Donner et al. 2023