Name: Ipertermia maligna (MH)
Brand: Equigerminal
Price: 43.05 EUR

Informazioni sul test

Questo test del DNA rileva la Ipertermia Maligna (MH) mutazione, un disturbo genetico ereditario che interessa la funzione muscolare scheletrica nei Quarter Horse e nelle razze correlate.

Il test identifica se un cavallo è libero o affetto dalla mutazione dominante MH, supportando le decisioni di allevamento e la gestione clinica prima dell'anestesia o di esercizi intensi.

Perché testare?

Questo test genetico aiuta a:

Identificare i cavalli portatori della mutazione dominante MH.
Supportare decisioni di allevamento responsabili.
Valutare il rischio di ipertermia maligna prima dell'anestesia.
Individuare cavalli a rischio aumentato di crisi muscolari indotte da esercizio o stress.
Rilevare cavalli che potrebbero anche beneficiare di ulteriori test PSSM1. testing.

Segni clinici

Signs usually appear in adult horses. Two kinds of attack are on record.

Attacks under anaesthesia:

Body temperature climbing fast, recorded between 40 and 45 degrees Celsius. In one monitored case it rose about 0.12 degrees every minute.
A racing heart that loses its rhythm, and high blood pressure
Heavy sweating. The anaesthetic tubing becomes hot to the touch.
Muscles locking up: first in one place, such as the ears drawn in or the jaw clamped shut, then all over, with the third eyelid showing and the eye pulled back into the socket
The blood turning acid, with carbon dioxide building up even though the horse is on a ventilator with pure oxygen
Blood salts out of balance, thickened blood, high blood sugar, struggling kidneys and muscle breakdown products rising fast
Death, with the body stiffening unusually quickly afterwards

Attacks with no anaesthetic involved:

Severe, sudden muscle breakdown with a body temperature recorded between 40.2 and 43.3 degrees Celsius
Episodes that look like colic, locked muscles, a stiff way of going, tiring quickly, sweating on and off, a fast heart and fast breathing
Extremely high muscle enzymes on a blood test, and acid blood
Muscle enzymes that stay raised between attacks, in horses that otherwise look well
Sudden death, including death out in the field on an unusually hot day

What sets off an attack: every gas anaesthetic of the halogenated family (halothane, isoflurane, desflurane, sevoflurane) and muscle relaxants such as succinylcholine. Also exercise, the stress of transport or a new place, the start of training, the excitement of breeding, extreme heat, and another illness or muscle disease at the same time.

An attack is a veterinary emergency. What is reported to save horses: spotting it early, stopping the anaesthetic gas or muscle relaxant at once, cooling the body actively, and giving dantrolene.

None of these signs is unique to MH. They also happen under anaesthesia and after hard work for other reasons. Your veterinarian makes the diagnosis from the history, the examination, blood results and this genetic result.

Trasmissione

MH is dominant. One copy is enough to make a horse susceptible. The gene is not on a sex chromosome, so colts and fillies are affected equally. Through a positive parent, the variant can pass into other breeds and lines.

What each mating can produce:

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

No horse with two copies has been found yet. The researchers put this down to how rare the disease is, not to any evidence that two copies would be lethal.

Prevenzione

There is no cure. The result guides two things.

Managing a positive horse. This part saves lives, and it belongs to your veterinarian:

Ask your veterinarian to record the result in the horse's clinical file, so it is known before any general anaesthesia and in an emergency
Medication can be given before anaesthesia to reduce the severity of an attack
Avoid the other triggers listed under Clinical signs where you can
A horse that also carries PSSM1 needs that condition managed as well

Breeding. Breeding from positive horses is discouraged. Test breeding stock before mating, and if a positive horse is used, choose a partner that tested negative.

Risultati

Il test del DNA verifica la presenza del gene dominante MH e presenta i risultati come uno dei seguenti:

N/ - Negativo per MHAssenza dell'allele responsabile della Ipertermia Maligna (MH).
MH/N - Affetto - Eterozigote positivo per MHPresenza di una copia dell'allele responsabile della MH. Il cavallo è affetto dal disturbo MH e può trasmettere l'allele MH al 50% della sua progenie durante l'allevamento.
MH/ -Affetto - Omozigote positivo per MHPresenza di due copie dell'allele responsabile della MH. Il cavallo è affetto dal disturbo MH e trasmetterà l'allele MH al 100% della sua prole.

Requisiti di esempio

30 a 40 - radici dei capelli - busta o 5 mL - sangue - tubo K3 EDTA

Tempi di consegna

2 a 5 giorni lavorativi

Come funziona

🛒 Acquista il test: seleziona e acquista il test online.

📧 Ricevi le istruzioni: dopo la conferma del pagamento, ricevi via e-mail le istruzioni per il prelievo del campione.

📄 Compila il modulo: stampa e compila il modulo di invio campioni con l’identificazione dell’animale.

✨ Raccogli il campione: strappa da 20 a 40 radici di pelo con il bulbo e incollale nell’area indicata del modulo, oppure chiedi al tuo veterinario di prelevare il sangue in una provetta K3-EDTA.

📮 Invialo al laboratorio: Equigerminal, S.A., HIESE, Rua da Quinta do Sobreiro, 25, Quinta Vale do Espinhal, 3230-343 Penela, PORTUGAL.

📊 Ricevi il referto: il referto certificato viene emesso non appena l’analisi è convalidata.

Domande frequenti

Quali campioni possono essere inviati?

Il test può essere eseguito utilizzando 30–40 radici di capelli o 5 mL di sangue raccolto in una provetta K3 EDTA.

Perché dovrei testare per l'Ipertermia Maligna?

Il test identifica i cavalli portatori della mutazione MH, permettendo decisioni di allevamento informate e aiutando i veterinari a ridurre i rischi anestetici tramite una gestione appropriata.

Quali cavalli sono più comunemente colpiti?

La mutazione si trova principalmente nei Quarter Horses e razze correlate, anche se il test può essere appropriato ogni volta che c'è una genealogia rilevante o sospetto clinico.

Dovrei testare anche per PSSM1?

Sì. I cavalli portatori di entrambe le mutazioni MH e PSSM1 possono sviluppare segni clinici più gravi, quindi si raccomanda il test per entrambe le condizioni nelle razze suscettibili.

Quanto tempo ci vuole per ricevere i risultati?

I risultati sono disponibili entro 2 a 5 giorni lavorativi dall'arrivo del campione in laboratorio.

For Professionals

Genetic and clinical detail for veterinarians, geneticists and laboratories.

Gene / locus: RYR1 (ryanodine receptor 1), ECA10.
Variant: missense Arg to Gly. HGVS (EquCab3.0): NC_009153.3:g.9678680C>G; XM_023649662.1:c.7363C>G; XP_023505430.1:p.(Arg2455Gly).
Alternative designations: published as c.7360C>G, p.(Arg2454Gly) (R2454G; Aleman et al., 2004). OMIA restates it against transcript XM_023649662.1, giving c.7363C>G and R2455G; both designations refer to the same genomic change. Laboratories differ in which they print, so quote both when comparing reports.
Discovery: candidate-gene approach from the homologous disease in pigs and humans; the change was found in two affected horses (Aleman et al., 2004). The homologous position is altered in two of the five known human malignant hyperthermia susceptibility types.
Mechanism: RYR1 encodes the calcium release channel of skeletal muscle. In susceptible horses the channel can be forced open, flooding the cell with calcium; hypermetabolism follows, with intense heat production and acidosis, and often death.
Variant identifiers: no rs/EVA identifier listed in OMIA; OMIA variant 159.
Variant classification: not currently evaluated (ISAG/AVCG, per OMIA).
Inheritance: autosomal dominant (OMIA code D), inferred from two heterozygous affected horses; no formal pedigree analysis has been published (Aleman et al., 2004, as cited in OMIA).
Penetrance / expressivity: estimated mortality 34% in susceptible horses under halothane anaesthesia (Aleman et al., 2009). PSSM phenotype is more severe in horses carrying both RYR1 and GYS1 variants (McCue et al., 2009).
Breeds with documented carriers or cases: Quarter Horse, Appaloosa, American Paint Horse (OMIA variant record). All horses in the first clinical series were Quarter Horses of halter lines. The clinical syndrome has also been reported in Thoroughbreds, Arabians and ponies, not all attributed to this variant.
Allele / carrier frequencies: among 159,227 horses of 16 breeds, the variant was found in 391 Quarter Horses, 18 Paint Horses, 1 Appaloosa and 1 Quarter Horse x Clydesdale; allele frequency 0.13% in Quarter Horses and 0.12% in Paint Horses and Appaloosas (Aleman, McCue and Bellone, 2025).
Clinical notes for veterinarians: consider concurrent GYS1 (PSSM1) testing in Quarter Horse-related breeds.

Key references:

Aleman M, Riehl J, Aldridge BM, LeCouteur RA, Stott JL, Pessah IN (2004). Association of a mutation in the ryanodine receptor 1 gene with equine malignant hyperthermia. Muscle Nerve 30:356-365. doi:10.1002/mus.20084. PMID 15318347.
Aleman M, Nieto JE, Magdesian KG (2009). Malignant hyperthermia associated with ryanodine receptor 1 mutation in Quarter Horses. J Vet Intern Med 23:329-334. doi:10.1111/j.1939-1676.2009.0274.x.
McCue ME, Valberg SJ, Jackson M, Borgia L, Lucio M, Mickelson JR (2009). Polysaccharide storage myopathy phenotype in Quarter Horse-related breeds is modified by the presence of an RYR1 mutation. Neuromuscul Disord 19:37-43. doi:10.1016/j.nmd.2008.10.001.
Aleman M, McCue M, Bellone RR (2025). Allele frequencies and genotypes for the ryanodine receptor 1 variant causing malignant hyperthermia and fatal rhabdomyolysis with hyperthermia in horses. J Vet Intern Med 39:e70081. doi:10.1111/jvim.70081.
Sperandio LMS, Lago GR, Albertino LG, Araujo CET, Ferreira C, Borges AS, Oliveira-Filho JP (2024). Allele frequency of muscular genetic disorders in bull-catching (vaquejada) Quarter Horses. J Equine Vet Sci 136:105052. doi:10.1016/j.jevs.2024.105052.