Staffordshire Bull Terrier: the two DNA tests to insist on before buying a puppy
The Staffordshire Bull Terrier is one of those breeds where genetics has delivered a clean answer: two of its heaviest inherited conditions are recessive, caused by an identified mutation, and detectable from a cheek swab. A serious breeder will show you the results without being asked. The Staffordshire Bull Terrier breed profile puts them in context.
L-2-hydroxyglutaric aciduria
This is a neurometabolic disease whose causal mutation was identified by Jacques Penderis, C. Abramson, Cathryn Mellersh and colleagues in a paper published in 2007 in the Journal of Medical Genetics: a double substitution in exon 10 of the L2HGDH gene, with perfect segregation across 21 affected dogs, 11 obligate carriers and 127 related controls (study on Google Scholar). That perfect segregation is what made a reliable DNA test possible. Clinically, the study by A. Shea, Luisa De Risio and colleagues, published in 2016 in The Veterinary Record on 27 affected Staffordshire Bull Terriers, describes a mean age of onset of 12 months with a range from 2.5 months to 5 years, stiffness in all four limbs in 24 dogs out of 26 as the earliest sign, behavioural change in 24 of 27, and seizure-like or dyskinetic episodes in 18 (study on Google Scholar). One reassuring and often-overlooked finding: 19 of the 27 dogs were still alive after a mean survival of more than six years from first signs. The disease is progressive but manageable — it is not a death sentence.
Juvenile hereditary cataract
This one involves a different gene. Cathryn Mellersh, Louise Pettitt, Oliver Forman and Keith Barnett identified, in a study published in 2006 in Veterinary Ophthalmology, a single-nucleotide insertion in exon 9 of the HSF4 gene causing a recessive hereditary cataract in the Staffordshire Bull Terrier (study on Google Scholar). Clouding appears early in life and progresses to complete blindness by around three years in affected dogs. Here too, the test comes long before the signs — which is exactly the point.
What testing has already changed
The best argument for demanding those results has been measured. Thomas Lewis and Cathryn Mellersh analysed, in a study published in 2019 in PLOS ONE using UK Kennel Club data, the effect of commercial DNA tests on eight disorders across eight breeds: in the Staffordshire Bull Terrier, the frequency of the HSF4 allele fell from 0.67% before the test to 0.09% after, a drop of nearly 86% (study on Google Scholar). A breed can therefore erase an inherited disease in a handful of generations — provided buyers ask for the paperwork.
How to read the results
Both conditions are autosomal recessive. Each test returns one of three statuses: clear, carrier, affected. A carrier is perfectly healthy; it only becomes a problem when mated to another carrier, in which case on average a quarter of the puppies will be affected. A litter is therefore safe as long as at least one parent is clear for the condition in question. Note that a puppy whose parents are both tested clear is "hereditarily clear" — valid, provided parentage is verified. A mean onset at 12 months also means no clinical examination of a puppy replaces the test: there is nothing to see at eight weeks.
The rest of the budget
Neurological work-ups, MRI or cataract surgery quickly run into thousands, and these conditions are excluded once already declared. Our benchmarks are in insuring a Staffordshire Bull Terrier and in pet insurance for dogs. For the daily life of a powerful, playful dog, see our tough toys for Staffordshire Bull Terriers and the dog care and grooming section.
Frequently asked questions
Can an adult dog already bought be tested?
Yes, from a cheek swab or blood sample at any canine genetics laboratory. It matters most if you are considering breeding from the dog.
Should a carrier be removed from breeding?
No, and removing every carrier would narrow the gene pool. It simply must never be mated to another carrier of the same mutation.
Is there a treatment for L-2-HGA?
No curative treatment. Management targets seizure control and comfort; many dogs live for years after diagnosis.
This guide is part of Planète Pets’s Dogs universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.