Test Detail

Multi-disease panel for the Irish Soft Coated Wheaten Terrier that groups five molecular tests: degenerative myelopathy (SOD1, exon 2), hyperuricosuria (SLC2A9), congenital microphthalmia with coloboma (RBP4), paroxysmal dyskinesia (PIGN) and protein-losing nephropathy (PLN, NPHS1/KIRREL2 risk haplotype). It combines neurological, neuromuscular, ocular, urinary and renal conditions. Hyperuricosuria due to SLC2A9 is a pan-breed variant with no specific documentation in the Soft Coated Wheaten Terrier.

Applicable breed: Irish Soft Coated Wheaten Terrier. RBP4 microphthalmia has been described in lines of the breed and PxD in clinical cohorts of the breed (Kolicheski et al., 2017). PLN is relatively common in the SCWT, with a reported mean onset of around 6.3 ± 2.0 years (Littman et al., 2013). No reliable country-specific carrier frequencies in the breeding population are published (limited data). The SLC2A9 variant of hyperuricosuria is pan-breed and is not specifically documented in the Soft Coated Wheaten Terrier (OMIA:001033-9615): its frequency in the breed is unknown and the test should be interpreted as a general marker, not as breed-specific validation.

- Genotype breeding stock before mating; the panel covers five conditions in a single sample\n- DM and HUU (recessive; both pan-breed variants, with no documented frequency of their own in the breed): do not mate two carriers — 25% homozygotes per litter; carrier × clear produces no affected animals\n- RBP4 microphthalmia: interpret according to the sex of the breeding animal because of the maternal effect; homozygous females produce affected litters, so they must be excluded from breeding\n- PxD (PIGN, recessive): do not mate two carriers; exclude affected homozygotes from breeding\n- PLN: the molecular test does not replace monitoring of the urine protein/creatinine ratio (UPC) throughout the breeding animal's life; avoid matings between high-risk animals\n- After a confirmed clinical case, do not repeat the parental mating and communicate the status to the buyer

Check the exact panel offered by each laboratory. RBP4 microphthalmia has a maternal effect: a homozygous puppy born to a non-homozygous mother does not express the disease, so the genotype must be interpreted according to the sex of the breeding animal. PLN requires periodic renal monitoring (UPC and biochemistry); the molecular test does not rule out the disease since inheritance is complex. PxD is suspected from the episodes (video is key) and confirmed by PIGN testing after ruling out epilepsy, heart disease and orthopaedic causes. DM is a diagnosis of exclusion: rule out disc herniation, spinal cord compression and neoplasia before attributing the presentation to SOD1. HUU (SLC2A9) and DM (SOD1) are based on pan-breed variants with no specific frequency published in the SCWT; they should be interpreted as general carrier status and not as breed-specific validation.

1. Awano T et al. 2009. Genome-wide association analysis reveals a SOD1 mutation in canine degenerative myelopathy that resembles amyotrophic lateral sclerosis. Proc Natl Acad Sci U S A 106(8). PMID 19188595.
2. Coates JR et al. 2010. Canine degenerative myelopathy. Vet Clin North Am Small Anim Pract 40(5). PMID 20732599.
3. Bannasch D et al. 2008. Mutations in the SLC2A9 gene cause hyperuricosuria and hyperuricemia in the dog. PLoS Genet 4(11). PMID 18989453.
4. Karmi N et al. 2010. Validation of a urine test and characterization of the putative genetic mutation for hyperuricosuria in Bulldogs and Black Russian Terriers. Am J Vet Res 71(8). PMID 20673090.
5. Karmi N et al. 2010. Estimated frequency of the canine hyperuricosuria mutation in different dog breeds. J Vet Intern Med 24(6). PMID 21054540.
6. Kaukonen M et al. 2018. Maternal Inheritance of a Recessive RBP4 Defect in Canine Congenital Eye Disease. Cell Rep 23(9). PMID 29847795.
7. Kolicheski AL et al. 2017. A homozygous PIGN missense mutation in Soft-Coated Wheaten Terriers with a canine paroxysmal dyskinesia. Neurogenetics 18(1). PMID 27891564.
8. Littman MP et al. 2013. Glomerulopathy and mutations in NPHS1 and KIRREL2 in soft-coated Wheaten Terrier dogs. Mamm Genome 24(3-4). PMID 23325127.
9. Vaden SL et al. 2013. Familial renal disease in soft-coated wheaten terriers. J Vet Emerg Crit Care (San Antonio) 23(2). PMID 23461660.
10. OMIA:000263-9615 (Degenerative myelopathy), OMIA:001033-9615 (Urolithiasis/SLC2A9), OMIA:002151-9615 (Microphthalmia/RBP4), OMIA:002084-9615 (Dyskinesia, paroxysmal, PIGN-related).