Jack Russell Terrier
Jack Russell Terriers have a cited life expectancy of 13.3 years (McMillan 2024 / VetCompass, n=19,166, 95% CI 13.2 to 13.3). No carrier testing data for Jack Russell Terriers has been read in yet. 49 dogs stand behind the atlas figures here, so treat this page as an early sketch.
Also known as Jack, Jack Russel Terrier, and JRT.
What Jack Russell Terriers tend toward
Tendencies from owner surveys of purebred Jack Russell Terriers — a leaning across the breed, not a prediction for any one dog. A bar’s strength shows how much of that behavior breed actually explains: for most it’s faint, because the rest is your dog, their training, and the life you give them.
Other names
The Jack Russell Terrier is also recorded as Jack, Jack Russel Terrier, and JRT.
Identified as Jack Russell Terrier (VBO:0200724) in the Vertebrate Breed Ontology (Mullen et al. 2025, CC-BY 4.0) · registry IDs FCI 345 · iDog 357 · VeNom 15009.
For researchers Population genetics, disease models and every recorded condition Open the research detail for the Jack Russell Terrier
In the atlas, the Jack Russell Terrier clusters consistently as Jack Russell Terrier (100% of the 49 dogs here). Genetic diversity is high (mean heterozygosity 0.372), reflecting either a mixed-breed cluster or breeds with broad genetic backgrounds.
Ranks 100 of 107 on the bottleneck severity scale, among the most genetically diverse breeds in the atlas. Mean heterozygosity is 0.372, notably high, indicates broad genetic background.
What the atlas genotypes say about Jack Russell Terrier
Computed from the 14,478 CanVAS dogs in the Atlas, on an imputed genotype backbone: 77,215 directly typed sites per dog, imputed to 9.67 million variants.
The confidence below counts dogs, not reads: it is the size of the sample, and it is separate from how the genotypes were measured.
What does genetic diversity mean?
How varied a breed's gene pool is — the share of gene spots where a typical dog of the breed carries two different versions rather than two identical ones.
How to read it: Higher = more diverse. Among well-sampled breeds it ranges roughly 0.22 (least diverse) to 0.33 (most diverse).
Diversity is a strength, not a verdict on any individual dog. Lower diversity means it's worth paying attention to recessive-risk testing — not that a dog is doomed.
What does within-breed variation mean?
How much individual dogs within the breed differ from each other genetically.
How to read it: Higher = more internal variety among individuals of the breed.
Sensitive to how many dogs of the breed we've sampled.
What does typical lifespan mean?
The median age dogs of the breed tend to reach.
How to read it: Higher = longer-lived. Compare to longevity-for-size to see whether it's just a size effect.
Drawn from population lifespan records; individual dogs vary widely with care, genetics, and luck.
Jack Russell Terriers are a natural model for human disease
Because the same genes cause the same conditions across species, the inherited conditions documented in Jack Russell Terriers help researchers understand, and work toward treating, the human diseases they model. This is the dog advancing human medicine. The breed models the human disease; it does not have it, and this is not a prediction for your dog.
- amyotrophic lateral sclerosis type 1, modeled by the breed's Degenerative myelopathy via SOD1, the same underlying biology.
- hemophilia B, modeled by the breed's Haemophilia B via F9, the same underlying biology.
- autosomal recessive congenital ichthyosis 1, modeled by the breed's Ichthyosis, TGM1-related via TGM1, the same underlying biology.
- Duchenne muscular dystrophy, modeled by the breed's Muscular dystrophy, Duchenne type via DMD, the same underlying biology.
- myotonia congenita, autosomal recessive, modeled by the breed's Myotonia via CLCN1, the same underlying biology.
- severe combined immunodeficiency due to DNA-PKcs deficiency, modeled by the breed's Severe combined immunodeficiency disease, autosomal, PRKDC-related via PRKDC, the same underlying biology.
Every condition recorded in the Jack Russell Terrier
Beyond the testable carriers above, OMIA's literature catalogue records 19 genetic conditions in the Jack Russell Terrier, 17 of which have a known human equivalent. This is the documented landscape across all Jack Russell Terriers ever studied, not a prediction for any one dog.
- Degenerative myelopathy Autosomal recessiveHuman equivalent: amyotrophic lateral sclerosis type 1
- Haemophilia B X-linked recessiveHuman equivalent: hemophilia B
- Ichthyosis, TGM1-related Autosomal recessiveHuman equivalent: autosomal recessive congenital ichthyosis 1
- Muscular dystrophy, Duchenne type X-linked recessiveHuman equivalent: Duchenne muscular dystrophy
- Myotonia Autosomal recessiveHuman equivalent: myotonia congenita, autosomal recessive
- Severe combined immunodeficiency disease, autosomal, PRKDC-related Autosomal recessiveHuman equivalent: severe combined immunodeficiency due to DNA-PKcs deficiency
- Tail, short Autosomal dominantHuman equivalent: OMIM:182940
- Ataxia, cerebellar, KCNJ10-related Autosomal recessiveHuman equivalent: EAST syndrome
- Ataxia, SETX-related Probably autosomal recessiveHuman equivalent: OMIM:602433
- Ataxia, spinocerebellar, CAPN1-related Autosomal recessiveHuman equivalent: autosomal recessive spastic paraplegia type 76
- Choroidal hypoplasia, NHEJ1-related Autosomal recessiveHuman equivalent: OMIM:611290
- Coat colour, dilution, MLPH-related Autosomal recessiveHuman equivalent: Griscelli syndrome type 3
- Familial adenomatous polyposis Probably autosomal dominantHuman equivalent: familial adenomatous polyposis 1
- Lens luxation Autosomal recessiveHuman equivalent: Weill-Marchesani 4 syndrome, recessive
- Human equivalent: OMIM:155550
- Myasthenic syndrome, congenital, CHRNE-related Autosomal recessiveHuman equivalent: congenital myasthenic syndrome 4A
- XX difference of sexual development, generic MultifactorialHuman equivalent: 46,XX disorder of sex development
- Deafness, generic Multifactorial
Plus 1 more conditions recorded in the Jack Russell Terrier in OMIA.
Where every number on this page came from.
This page draws on three primary data sources. Carrier frequencies for the Mendelian section come from Donner et al. 2023 (CC-BY-4.0). We grade these data at evidence Limited because the cohort is a direct-to-consumer ascertainment, which biases toward owners who chose to test their dogs. The panel also uses tag-SNP proxies for some variants rather than direct causal-variant assays. Limited is a study-design grade, not a quality grade: the Donner cohort is the largest open canine-genotype dataset in existence and we are grateful for it. We rate the confounding MEDIUM.
Population-genetic dimensions (heterozygosity, intra-breed PCA distance, nearest neighbors, trait-locus frequencies) come from CanVAS (Brundage 2026), harmonized through the Sniff Atlas. The exact release date and verification commit are pinned at the bottom of the page so a researcher can trace a number back to a specific snapshot. The disease-gene-variant graph comes from OMIA (Online Mendelian Inheritance in Animals; Nicholas, Tammen, and the Sydney Informatics Hub at the Sydney School of Veterinary Science, The University of Sydney; retrieved April 2026, DOI 10.25910/2AMR-PV70).
What this page does not yet have. Inheritance modes and per-disease penetrance evidence from Donner 2023 are in the structured data for every variant the panel covers. Mondo, OMIM, Ensembl, and HGNC cross-references live on the gene and disease pages this page links to, rather than being repeated here. What is still absent from this breed page is anything not in the cited panel, and each such gap carries its cause where it appears.
How to cite this page. The computed dimensions on this page are derived from the open Sniff Atlas v1.0.1 (Gehring 2026, doi:10.5281/zenodo.20566358, CC-BY 4.0). Full citation formats including BibTeX, RIS, and CITATION.cff at sniff.world/cite.
Some things about living with a jack russell terrier never make it into a database. Add what you know as a Keeper, in your words →
Lived experience, kept beside the science.We have 49 jack russell terriers. We do not have yours.
Every jack russell terrier added sharpens the breed's genetic neighborhood. Enrollment is free. The data stays open. The star is permanent.
- 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. doi:10.1371/journal.pgen.1010651
- Brundage DM (2026). CanVAS: A Harmonized and Imputed Canine Variant Atlas. bioRxiv. doi:10.64898/2026.04.13.718238
- Nicholas, F.W., Tammen, I., & Sydney Informatics Hub. (2026). Online Mendelian Inheritance in Animals (OMIA) [dataset]. The University of Sydney. https://omia.org. doi:10.25910/2AMR-PV70 (retrieved April 2026).