Skip to main content
snıff
Canine Mendelian disease record

Spondylocostal Dysostosis (Discovered in the Miniature Schnauzer)

Spondylocostal Dysostosis (Discovered in the Miniature Schnauzer). Autosomal recessive. Observed in 0 of 266 breeds tested in the Sniff Atlas, with measured variant frequencies drawn from 242,661 dogs (Donner 2023). Whether a dog carrying this variant is at risk depends on the disease’s inheritance pattern; outcome also depends on penetrance, modifiers, and environment. The frequencies below describe variant prevalence, not confirmed disease incidence.

OMIA identifier
OMIA:001944-9615
Autosomal recessive
Linked gene
HES7
Human counterpart
In humans, this gene is HES7. In people, HES7 appears tolerant of loss-of-function variation (gnomAD v4.1 constraint, LOEUF 1.32). Constraint measures intolerance to loss-of-function only and does not indicate importance; some tolerant genes cause disease through other mechanisms. In people, variants in the HES7 gene have conflicting classifications in ClinVar, and none is expert-reviewed. The evidence is unsettled, not that variants here are benign.
Source dataset
Sniff Atlas v1.0.1 / DOI
The human connection

A model of human spondylocostal dysostosis 4, autosomal recessive

Dogs with this condition carry a change in HES7. In people, changes in the same gene cause spondylocostal dysostosis 4, autosomal recessive. 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: Any autosomal recessive spondylocostal dysostosis in which the cause of the disease is a mutation in the HES7 gene.

In humans it is also called: SCDO4, spondylocostal dysostosis 4.

MONDO:0013366 OMIM 613686

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

Also called Comma defect (Willet et al., 2015), "due to the gross anatomical shape of the abnormal pups".

Clinical features

As reported by Willet et al. (2015), "The condition is characterised by truncal shortening, extensive hemivertebrae and rib anomalies including malalignment, fusion and reduction in number." Also, "The three affected pups were born stillborn or died within hours of birth. Gross external examination of the pups by the attending veterinarian revealed a reduction in body length compared with normal littermates (data not available). The hindquarters of affected pups were reduced in size compared to the forequarters, giving an overall comma-like morphology to the body". One of the affected samples had umbilical hernia and another had a cleft hard palate.

Molecular genetics

Comparative analysis by Willet et al. (2015), based on location and phenotype in the mouse, revealed 19 positional comparative candidate genes. Whole-genome sequencing of two of the affected sibs revealed 5 candidate functional mutations, which were subsequently narrowed down to the causal mutation, a "guanine deletion at CFA5:35,940,090 (CFA5:32,945,846 in canFam3.1) within exon 2 of HES7 (c.126delG) . . . [which] introduces a frameshift mutation, causing alteration from the 43rd amino acid onwards and resulting in a premature termination codon in place of the 66th amino acid (p.(Thr43ProfsTer24))". Genotyping for this mutation in 133 dogs, including the three affected dogs and extended family members, confirmed this as the causal mutation.

Prevalence

Willet et al. (2015) tested 127 Miniature Schnauzers and six Standard Schnauzers for the deletion. Only the three affected pups tested homozygous for the mutant allele, and four family members tested heterozygous, giving an estimated allele frequency of 0.04 for the eastern Australian population tested. Carrier imported family members from Sweden and Argentina suggest that the allele may be globally dispersed.

Inheritance

The three-generation pedigree reported by Willet et al. (2015) was consistent with autosomal recessive inheritance, which was confirmed with genotyping of the causal mutation in the extended family of the affected dogs.

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 613686 Gene · OMIM 608059

Source: OMIA (Nicholas, Tammen & the Sydney Informatics Hub), entry OMIA:001944-9615, 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.

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.

Your breed

See what Spondylocostal Dysostosis (Discovered in the Miniature Schnauzer) looks like in your dog's breed.
Variant frequency by breed

Observed only in small-sample breeds

Maximum variant frequency per breed across variants in the Donner 2023 cohort, with . 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.

Scope of this record

Scope

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 variant frequency is measured; phenotype outcome depends on penetrance, environment, and modifier loci. Consult a veterinarian for clinical interpretation.

How to cite this record

Citations

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:001944-9615.

  • 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.

Related

Related

Last updated
Sources: Sniff Atlas v1.0.1 · OMIA OMIA:001944-9615 · Donner et al. 2023 · gnomAD v4.1 (Karczewski 2020) · ClinVar (Landrum 2018)