Tobiano - frakkemønster
DNA-testen verificerer tilstedeværelsen af den kromosomale inversion. Tobiano-frakkemønsteret involverer normalt noget hvidt på alle fire ben og afrundede hvide pletter...
€43.05 Inkl. moms
Om testen
Denne DNA-testdetekterer Tobiano (TO) kromosomal inversionen, den dominante genetiske variant, der er ansvarlig for Tobiano-hvide pletter hos heste. Testen afgør, om en hest er negativ, heterozygot eller homozygotfor Tobiano-allelen, hvilket giver værdifuld information til forudsigelse af pelsfarve og avlsbeslutninger.
Hvorfor teste?
Test anbefales for at:
- Bestemme hestens Tobiano genotype.
- Identificere heterozygote (TO/N)og homozygote (TO/TO)Tobiano-heste.
- Forudsige sandsynligheden for at producere Tobiano-afkom.
- Støtte selektive avlsprogrammer.
- Kombineres med basisfarve-test (Extension og Agouti) for en mere præcis forudsigelse af afkommets pelsfarver.
Kliniske tegn
Tobiano is a coat pattern, present at birth. It is not linked to any disease.
Without Tobiano: no tobiano pattern. The horse can still have face and leg markings, or white from other genes.
With one or two copies: the same tobiano pattern. The eye cannot tell one copy from two.
- White patches with smooth, rounded, clear edges
- One or more white patches usually cross the back
- The lower legs are usually white
- The head is usually coloured, with ordinary face markings like a solid horse
- The tail is often two-coloured
- White covers roughly 20 to 80% of the body
What can fool the eye:
- A tobiano with very little white, read as a solid horse with big markings
- Tobiano and frame overo together, called tovero, where the patterns mix
Transmission
Tobiano is dominant. One copy is enough for the pattern to show. The gene is not on a sex chromosome, so colts and fillies are the same.
What each mating can produce:
- N/N x N/N gives 100% N/N: no tobiano foals
- N/N x To/N gives 50% N/N, 50% To/N: one foal in two tobiano
- N/N x To/To gives 100% To/N: every foal tobiano
- To/N x To/N gives 25% N/N, 50% To/N, 25% To/To: three foals in four tobiano
- To/N x To/To gives 50% To/N, 50% To/To: every foal tobiano
- To/To x To/To gives 100% To/To: every foal tobiano
Tobiano does not skip a generation. A solid foal from a tobiano parent cannot pass it on.
Forebyggelse
To be sure of a tobiano foal, use a parent with two copies.
Check frame overo too. A tobiano horse can carry frame overo without showing it, and two frame overo carriers can produce a lethal white foal. Before mating two spotted horses, test both parents with the Overo test as well.
Colour should not be the only thing that decides a mating. This test says nothing about health, performance or temperament.
Resultater
DNA-testen verificerer tilstedeværelsen af den kromosomale inversion og præsenterer resultaterne som et af følgende:
- N/– Ikke-tobianohest.
- To/N– Positivfor den dominante Tobiano-genmutation, bærer af en enkelt arvet kopi af Tobiano. Hestens grundfarve kan ændres i varierende grad af Tobiano-aftegningerne.
- To/– Positivfor dominant Tobiano-genmutation, bærer af to arvede kopier af Tobiano. Vil altid videregive Tobiano til føl. Til avlsformål er homozygote Tobiano-heste yderst ønskværdige, da de med sikkerhed vil producere Tobiano-føl uanset deres mage.
Krav til prøver
30 til 40 - hårrødder - kuvert eller 5 mL - blod - K3 EDTA-rør
Send din prøve med almindelig post eller ekspreslevering til:
Equigerminal Lab HIESE
Rua da Quinta do Sobreiro Nº25
3230-343 Penela, Portugal
Behandlingstid
2 til 5 hverdage
Sådan fungerer det
🛒 Køb testen:Vælg og køb testen online.
📧 Modtag instruktioner:Efter bekræftelse af betalingen modtager du instruktioner til prøvetagning.
✨ Prøvetagning:Din dyrlæge indsamler hårrødder eller en blodprøve.
📄 Download indsendelsesformular:Download den printbare indsendelsesformular.
📮 Send prøver:Send dine prøver med almindelig post eller ekspreslevering til:
Equigerminal Lab HIESE
Rua da Quinta do Sobreiro Nº25
3230-343 Penela, Portugal
📄 Modtag resultater:Få dit resultatcertifikat via e-mail.
Ofte stillede spørgsmål
Hvilke heste skal testes?
Enhver hest, der udviser et Tobiano-pelsmønster eller er beregnet til avl, hvor arvelighed af pelsfarve er vigtig.
Bestemmer denne test hestens grundlæggende pelsfarve?
Nej. Tobiano-testen identificerer kun Tobiano-spætmønsteret. Grundlæggende pelsfarve bør bestemmes ved hjælp af tests som Extensionog AgoutiDNA-tests.
Hvorfor er homozygote Tobiano-heste værdifulde til avl?
Fordi TO/TOheste videregiver Tobiano-allelen til 100% af deres afkom, hvilket garanterer, at hvert føl vil arve Tobiano-mønsteret.
Hvilke prøver accepteres?
Testen kan udføres ved hjælp af 30-40 hårrøddereller 5 ml blod opsamlet i et K3 EDTA-rør.
Hvornår modtager jeg mine resultater?
Resultaterne er tilgængelige inden for 2 til 5 arbejdsdageefter prøvemodtagelse på laboratoriet.
For Professionals
Genetic and clinical detail for veterinarians, geneticists and laboratories.
- Gene / locus: Tobiano (TO) locus, ECA3; inversion breakpoint near KIT (KIT proto-oncogene, receptor tyrosine kinase), a gene involved in white spotting in horses. No gene is disrupted.
- Variant: chromosomal inversion of about 43 Mb on ECA3 (Brooks et al., 2007). No HGVS description is available in our sources.
- Variant classification: no OMIA variant entry for the tobiano inversion in the OMIA variant table (dump of 2026-09-19); no ISAG/AVCG classification available.
- Inheritance: autosomal dominant; To/N and To/To are phenotypically indistinguishable.
- Penetrance / expressivity: the inversion was present in every tobiano horse tested in German breeds (Haase et al., 2008).
- Breeds with documented carriers or cases: Brooks et al. (2007): American Miniature Horse, American Paint Horse, Arab and Pinto crosses, draft horses and draft crosses, Icelandic Horse, Missouri Fox Trotter, Pinto, Saddlebred, Shetland Pony, Spotted Saddle Horse, Tennessee Walking Horse, Welsh crosses. Haase et al. (2008): German breeds, including the Lewitzer, the Tinker, German ponies and Pinto horses and ponies. Absence from these lists means not reported, not proven absent.
- Allele / carrier frequencies: about 36% of horses registered with the American Paint Horse Association are reported to be tobiano (Magdesian et al., 2009). No breed-level allele or carrier frequency study identified in our sources; 0 of 58 Thoroughbreds carried the inversion (Brooks et al., 2007). Of 109 tobiano horses from white-patterned bloodlines (over 90% of the study samples were registered Paint horses), 11 (10%) also carried the EDNRB frame overo allele (Santschi et al., 2001), the variant associated with lethal white foal syndrome (Metallinos et al., 1998).
- Clinical / diagnostic notes for veterinarians: the main use is zygosity testing. Loci of the other white patterns: EDNRB (frame overo), KIT (dominant white, sabino), MITF/PAX3 (splashed white).
Key references:
- Brooks SA, Lear TL, Adelson DL, Bailey E (2007). A chromosome inversion near the KIT gene and the Tobiano spotting pattern in horses. Cytogenet Genome Res 119:225-230.
- Haase B, Jude R, Brooks SA, Leeb T (2008). An equine chromosome 3 inversion is associated with the tobiano spotting pattern in German horse breeds. Anim Genet 39:306-309.
- Metallinos DL, Bowling AT, Rine J (1998). A missense mutation in the endothelin-B receptor gene is associated with Lethal White Foal Syndrome: an equine version of Hirschsprung disease. Mamm Genome 9:426-431.
- Santschi EM, Vrotsos PD, Purdy AK, Mickelson JR (2001). Incidence of the endothelin receptor B mutation that causes lethal white foal syndrome in white-patterned horses. Am J Vet Res 62:97-103.
- Magdesian KG, Williams DC, Aleman M, LeCouteur RA, Madigan JE (2009). Evaluation of deafness in American Paint Horses by phenotype, brainstem auditory-evoked responses, and endothelin receptor B genotype. J Am Vet Med Assoc 235:1204-1211.