Produktformular

Dødeligt hvidt føl-syndrom - LWFS

Name: Dødeligt hvidt føl-syndrom - LWFS
Brand: Equigerminal
Price: 329.0 DKK

DNA-test for Overo-genet, der er forbundet med Lethal White Foal Syndrome (LWFS). Eksempel 30 til 40 - hårrødder - konvolut...

329,00 kr Inkl. moms

Om testen

Denne DNA-test påviser den Frame Overo (O) genetiske variant, som er forbundet med Frame Overo pelsmønstretog Lethal White Foal Syndrome (LWFS).

Testen identificerer heste, der er frie, bærere eller homozygote for mutationen, hvilket understøtter ansvarlige avlsbeslutninger og reducerer risikoen for at producere syge føl.

Hvorfor teste?

Denne gentest anbefales til at:

Identificere heste, der bærer Frame Overo-mutationen.
Understøtte ansvarlige avlsbeslutninger.
Forhindre fødsel af føl, der er ramt af Lethal White Foal Syndrome (LWFS).
Bekræfte den genetiske status for heste med Frame Overo eller andre pelsmønstre, da mutationen også kan forekomme hos ensfarvede eller tobiano heste.

Kliniske tegn

Signs are seen only in newborn foals that inherited the change from both parents:

Born looking almost pure white
Unable to pass droppings, with signs of colic in the first hours of life, because the nerves that drive the last part of the bowel never developed
Death within the first 72 hours. Affected foals are usually put down sooner, for humane reasons.

The condition always kills, and there is no treatment. The diagnosis is made by a veterinarian, combining the examination and this genetic result.

Transmission

This variant behaves in two ways at once. For the coat pattern it is dominant: one copy is enough to give the frame overo pattern. For the fatal disease it is recessive: two copies are needed, one from each parent. The gene is not on a sex chromosome, so colts and fillies are affected equally.

What each mating can produce:

n/n x n/n gives 100% n/n
n/n x n/O gives 50% n/n, 50% n/O
n/O x n/O gives 25% n/n, 50% n/O, 25% O/O

These are chances for each foal, and they are the same for every pregnancy, whatever happened before.

Forebyggelse

Prevention is a breeding decision, and a completely effective one.

Breeding. Test both parents before mating and never mate two carriers. A carrier mated to a partner that tested negative cannot produce an affected foal.

Keeping the pattern. Carrying the change is not a reason to leave a horse out of breeding. Testing lets you breed for the frame overo pattern safely.

Do not rely on appearance. Some frame overo horses do not carry the change, and solid-coloured and tobiano horses have been found to carry it. Only a test result rules it out.

Resultater

DNA-testen verificerer tilstedeværelsen af den mutation, der er forbundet med Overo, og præsenterer resultaterne som et af følgende:

N/– Non-Overoeller 'ensfarvet' hest
O/N– Frame Overohest. Hesten bærer kun en enkelt kopi af frame Overo. Da frame Overo er et dominant gen, bør pelsmønsteret være til stede hos alle heste med en enkelt kopi af det muterede gen.
O/– En Lethal White Foal Syndrome(LWFS). Føllet bærer to kopier, homozygot for frame Overo. Da ingen levende frame Overo-heste, der er mere end en uge gamle, vil teste som homozygote, gælder det kun for heste med Lethal White-tilstanden.

Krav til prøver

30 til 40 - hårrødder - kuvert eller 5 mL - blod - K3 EDTA-glas

Behandlingstid

2 til 5 arbejdsdage

Sådan fungerer det

🛒 Koop de test: kies de test en koop hem online.

📧 Ontvang de instructies: na bevestiging van de betaling ontvangt u de instructies voor het afnemen van het monster per e-mail.

📄 Vul het formulier in: print het inzendformulier en vul het in met de identificatie van het dier.

✨ Neem het monster af: trek 20 tot 40 haren met wortel (bulbus) uit en plak ze in het gemarkeerde vak op het formulier, of laat uw dierenarts bloed afnemen in een K3-EDTA-buis.

📮 Stuur het naar het laboratorium: Equigerminal, S.A., HIESE, Rua da Quinta do Sobreiro, 25, Quinta Vale do Espinhal, 3230-343 Penela, PORTUGAL.

📊 Ontvang het rapport: het gecertificeerde rapport wordt uitgegeven zodra de analyse is gevalideerd.

Ofte stillede spørgsmål

Hvilke prøver kan indsendes?

Testen kan udføres med 30–40 hårrøddereller 5 ml blod opsamlet i et K3 EDTA-rør.

Hvorfor skal jeg teste for Frame Overo-genet?

Testning identificerer heste, der bærer mutationen forbundet med Frame Overo, og hjælper med at forhindre avlskombinationer, der kan producere føl ramt af Lethal White Foal Syndrome.

Kan en hest bære mutationen uden et tydeligt Frame Overo-mønster?

Ja. Nogle heste med ensfarvede pelse eller andre hvide mønstre, herunder tobiano, kan bære mutationen. DNA-testning er den eneste pålidelige måde at bestemme genetisk status på.

Hvad forårsager Lethal White Foal Syndrome?

LWFS opstår, når et føl arver to kopier (O/O)af Frame Overo-mutationen, én fra hver forælder.

Hvor lang tid tager det at modtage resultaterne?

Resultater er tilgængelige inden for 2 til 5 arbejdsdageefter prøvens ankomst til laboratoriet.

For Professionals

Genetic and clinical detail for veterinarians, geneticists and laboratories.

Gene / locus: EDNRB (endothelin receptor type B), ECA17.
Variant: Ile118Lys (I118K), dinucleotide substitution, missense. HGVS (EquCab3.0): NC_009160.3:g.50503041_50503042delinsCT; NM_001081837.2:c.353_354delinsAG; NP_001075306.2:p.(Ile118Lys).
Alternative designations: described in 1998 by three groups as Ile118Lys (Santschi et al., 1998; Metallinos et al., 1998) and as a dinucleotide mutation (Yang et al., 1998). The genomic record (delinsCT) and the cDNA record (delinsAG) describe the same change on opposite strands. Disease synonyms: overo lethal white foal syndrome (OLWS, OLWFS), lethal white overo (LWO); human homologue Hirschsprung disease.
Variant identifiers: no rs/EVA identifier listed in OMIA; OMIA variant 160.
Variant classification: not currently evaluated (ISAG/AVCG, per OMIA).
Mechanism: EDNRB steers the migration of one embryonic cell lineage that gives rise to both skin pigment cells and the enteric nerves of the gut wall. In heterozygotes, pigment cells fail to reach some areas, producing the white frame overo markings. Homozygous foals are almost entirely white and have myenteric aganglionosis with fatal functional intestinal obstruction (Santschi et al., 2001).
Inheritance: frame overo pattern autosomal dominant over solid colour; lethal white foal syndrome autosomal recessive (homozygotes only). OMIA code: A (autosomal).
Penetrance / expressivity: all OLWS foals tested were Lys118 homozygotes and no living homozygote was found (Santschi et al., 2001). The white pattern is incompletely expressed in heterozygotes: about 5% of phenotypic frame overos did not carry the allele, and two heterozygous Miniature Horses had no white markings (Santschi et al., 2001). Both 1998 American studies also found carriers among horses with no overo markings. 31 of 34 deaf or suspected-deaf American Paint Horses carried the variant (Magdesian et al., 2009).
Breeds with documented carriers or cases: American Paint Horse, Quarter Horse, Thoroughbred, Miniature Horse (OMIA variant record). Best documented in the American Paint Horse.
Allele / carrier frequencies: allele frequency 10.7% in 180 control American Paint Horses; not detected in 651 elite performance and 200 control American Quarter Horses (Tryon et al., 2009). Carrier frequency by pattern (Santschi et al., 2001; 945 white-patterned and 55 solid horses): frame 178/188 (95%), frame blend 153/158 (97%), loud calico 37/37 (100%), medicine hat 9/13 (69%), tovero 49/84 (58%), calico 21/38 (55%), bald-faced 6/17 (35%), sabino 3/15 (20%), breeding-stock solid 26/146 (18%), splashed white 3/26 (12%), tobiano 11/109 (10%), minimal calico 6/67 (9%), non-frame blend 0/14, solid-coloured horses of other breeds 0/55. In Brazil, estimated carrier frequency in American Paint Horses was 21.6% overall and 89.5% among overo horses (Badial et al., 2018).
Clinical / diagnostic notes for veterinarians: the laboratory genotypes this variant only (0, 1 or 2 copies); KIT, MITF and PAX3 white-spotting variants are not detected. In extensively white heterozygotes, hearing can be assessed by brainstem auditory-evoked response testing (Magdesian et al., 2009).

Key references:

Santschi EM, Purdy AK, Valberg SJ, Vrotsos PD, Kaese H, Mickelson JR (1998). Endothelin receptor B polymorphism associated with lethal white foal syndrome in horses. Mamm Genome 9:306-309. PMID 9530628.
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.
Yang GC, Croaker D, Zhang AL, Manglick P, Cartmill T, Cass D (1998). A dinucleotide mutation in the endothelin-B receptor gene is associated with lethal white foal syndrome. Hum Mol Genet 7:1047-1052.
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. doi:10.2460/javma.235.10.1204.
Tryon RC, Penedo MCT, McCue ME, et al. (2009). Evaluation of allele frequencies of inherited disease genes in subgroups of American Quarter Horses. J Am Vet Med Assoc 234:120-125. doi:10.2460/javma.234.1.120.
Badial PR, Teixeira RBC, Delfiol DJZ, da Mota LSLS, Borges AS (2018). Validation of high-resolution melting analysis as a diagnostic tool for endothelin receptor B mutation in American Paint horses and allele frequency estimation. Mol Cell Probes 41:52-56. doi:10.1016/j.mcp.2018.08.002.
Keppers HA, Gonda MG (2025). Lethal white foal syndrome: a review. Can J Anim Sci 105:1-8. doi:10.1139/cjas-2024-0077.