How is Bald Thigh Syndrome (Discovered in Sighthounds) inherited in dogs?

Bald Thigh Syndrome (Discovered in Sighthounds) follows a Autosomal recessive inheritance pattern. It has been observed in 32 of 211 breeds screened in the Sniff Atlas.

Canine Mendelian disease record

Bald Thigh Syndrome (Discovered in Sighthounds)

Q: How well studied is Bald Thigh Syndrome (Discovered in Sighthounds) in dogs?

OMIA curates 3 peer-reviewed references for Bald Thigh Syndrome (Discovered in Sighthounds). The full, linked citation list is on this page.

Bald Thigh Syndrome (Discovered in Sighthounds). Autosomal recessive. Observed in 32 of 211 breeds tested in the Sniff Atlas, with measured carrier frequencies drawn from 12,296 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:002168-9615
Inheritance: Autosomal recessive
Source dataset: Sniff Atlas v1.0.1 / DOI

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

Brunner et al. (2019): "Bald thigh syndrome (BTS) is a hair loss disorder seen in Greyhounds and other sighthound breeds into which the Greyhound has been introgressed such as Whippets, Galgo Español, and Magyar Agár."

Clinical features

Brunner et al. (2019): "BTS is characterized by bilateral hair loss on the caudal and lateral thighs, but alopecia may extend to the distal hind legs, the ventral abdomen and the chest. In some cases even the ventral neck is involved. Dogs of any age and sex may be affected."

Molecular genetics

Brunner et al. (2019): "The genetic analysis revealed a missense variant in the IGFBP5 gene homozygous in all available Greyhounds and other sighthounds. Further research is required to clarify whether the IGFBP5 variant represents a predisposing genetic risk factor." Because of this cautious conclusion, this variant has not been included in the OMIA table of likely causal variants.

Pathology

Brunner et al. (2019): "While the histology is rather unspecific in most cases, trichogram analysis and scanning electron microscopy revealed severe structural abnormalities in hair shafts of affected dogs. This finding is supported by the results of the transcriptomic and proteomic profiling where genes and proteins important for differentiation of the inner root sheath and the assembly of a proper hair shaft were downregulated."

Inheritance

Brunner et al. (2019) concluded "that BTS [bald thigh syndrome] is caused by structural HS [hair shaft] defects which are associated with the downregulation of genes and proteins essential for HS differentiation and HS assembly. The underlying genetic defect has not yet been identified and we suggest a complex mode of inheritance."

Source: OMIA (Nicholas, Tammen & the Sydney Informatics Hub), entry OMIA:002168-9615, 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.

Bald thigh syndrome in sighthounds-Revisiting the cause of a well-known disease. · PLoS One · 2019 · PMID 30794648
Results of a web-based health survey of retired racing Greyhounds. · J Vet Intern Med · 2007 · PMID 18196733
Bald thigh syndrome of Greyhound dogs: gross and microscopic findings. · Veterinary Dermatology · 2000 · PMID 34644855

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 Bald Thigh Syndrome (Discovered in Sighthounds) 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 Bald Thigh Syndrome (Discovered in Sighthounds) looks like in your dog's breed.

Carrier frequency by breed

Top 12 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%50%100%

Whippet73.7% · n 59

73.7%n 59

Dutch Shepherd Dog6.6% · n 61

6.6%n 61

Bichon Frise3.8% · n 52

3.8%n 52

Russell Terrier3.7% · n 123

3.7%n 123

Pomeranian2.1% · n 121

2.1%n 121

Belgian Malinois1.5% · n 266

1.5%n 266

Lhasa Apso0.82% · n 61

0.82%n 61

Shih Tzu0.59% · n 85

0.59%n 85

Chihuahua0.35% · n 143

0.35%n 143

Kromfohrlander0.29% · n 172

0.29%n 172

Staffordshire Bull Terrier0.12% · n 412

0.12%n 412

Border Collie<0.1% · n 2,115

<0.1%n 2,115

n = 3,670 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 Bald Thigh Syndrome (Discovered in Sighthounds) is measured; phenotype outcome depends on penetrance and modifiers.

▸ Full table with Wilson 95% confidence intervals

Breed	Carrier frequency	Wilson 95% CI	n tested
Whippet	73.7%	[61.3%, 83.3%]	59
Dutch Shepherd Dog	6.6%	[2.6%, 15.7%]	61
Bichon Frise	3.8%	[1.1%, 13.0%]	52
Russell Terrier	3.7%	[1.5%, 8.6%]	123
Pomeranian	2.1%	[0.6%, 6.4%]	121
Belgian Malinois	1.5%	[0.6%, 3.8%]	266
Lhasa Apso	0.82%	[0.1%, 7.4%]	61
Shih Tzu	0.59%	[0.1%, 5.4%]	85
Chihuahua	0.35%	[0.0%, 3.3%]	143
Kromfohrlander	0.29%	[0.0%, 2.7%]	172
Staffordshire Bull Terrier	0.12%	[0.0%, 1.2%]	412
Border Collie	<0.1%	[0.0%, 0.2%]	2,115

▸ Also observed in 20 small-sample breeds (n < 50)

Frequencies in this section are statistical estimates with wide Wilson 95% confidence intervals (typically >20 percentage points). Treat these as "carriers observed but the true population frequency is not yet measurable" rather than as comparable to the well-sampled entries above.

Breed	Estimate	Wilson 95% CI	n tested
Borzoi	100.0%	[86.2%, 100.0%]	24
Greyhound	93.3%	[78.7%, 98.2%]	30
Italian Greyhound	90.9%	[62.3%, 98.4%]	11
Scottish Deerhound	83.3%	[55.2%, 95.3%]	12
Saluki	73.5%	[49.8%, 88.6%]	17
Sloughi	50.0%	[5.5%, 94.5%]	1
Papillon	33.3%	[6.1%, 79.2%]	3
Cirneco Del Etna	25.0%	[6.0%, 63.5%]	6
Afghan Hound	22.2%	[6.3%, 54.7%]	9
Lancashire Heeler	21.9%	[8.3%, 46.3%]	16
Flat Coated Retriever	18.8%	[4.5%, 53.3%]	8
Biewer Terrier	14.3%	[2.6%, 51.3%]	7
Continental Toy Spaniel	14.3%	[2.6%, 51.3%]	7
Russian Tsvetnaya Bolonka	12.5%	[2.9%, 40.2%]	12
Belgian Sheepdog	8.3%	[2.3%, 25.8%]	24
Maltese	8.3%	[1.5%, 35.4%]	12
Curly Coated Retriever	7.1%	[0.8%, 43.9%]	7
Azawakh	3.8%	[0.4%, 28.3%]	13
Rhodesian Ridgeback	3.6%	[0.6%, 17.7%]	28
Schipperke	1.5%	[0.2%, 12.6%]	34

179 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:002168-9615.
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:002168-9615, 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:002168-9615 · Donner et al. 2023