Test Detail

Genetic panel for the American Bully grouping five recessive hereditary conditions prevalent in bull/pit-type breeds: crd1-type progressive retinal atrophy (crd1-PRA, early photoreceptor degeneration), cystinuria (cystine stones in the urinary tract), hyperuricosuria/hyperuricaemia (HUU, risk of urate uroliths), neuronal ceroid lipofuscinosis (NCL, neurodegenerative degeneration of adult onset) and degenerative myelopathy (DM, exon 2 variant of SOD1). The American Bully descends from the American Staffordshire Terrier and shares several variants through a founder effect.

American Bully (and related pit/bull-type breeds). ARSG-related NCL is characterised in AmStaff/APBT (allele at 3.4 % in AmStaff, Donner 2023 n>1M); it is assumed to be shared with the American Bully by ancestry, with no published cases in the breed. For crd1-PRA, HUU and cystinuria in the American Bully, population figures are not reliably published (limited data).

- Genotype breeding animals for PDE6B, SLC2A9, ARSG, SOD1 exon 2 and the cystinuria variant before mating\n- Do not cross two carriers for the same variant\n- A carrier may be crossed with a clear animal and the offspring intended for breeding must be tested\n- After a confirmed case, do not repeat the parental cross and communicate the status to the buyer\n- For HUU and cystinuria, recommend diet and management (low purine, low methionine) even if the test is positive, and urinary monitoring\n- Remember that DM has incomplete penetrance: not all SOD1 homozygotes develop disease

crd1-PRA must be distinguished from other PRAs (prcd-PRA, etc.); the crd1 test does not exclude other forms. ARSG-related NCL has an adult presentation and must be differentiated from other degenerative ataxias. Cystinuria and HUU share a clinical presentation (urolithiasis) and require stone analysis. DM is only attributable to SOD1 after ruling out spinal cord compression (MRI, myelography).

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OMIA001674-9615 / OMIA000256-9615 / OMIA001033-9615 / OMIA001503-9615 / OMIA000263-9615.