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Testing for PSSM1

From 2018, the requirements for testing/being tested on PSSM1, at the request of the GMM, have been tightened.

In short, this comes down to the following;

  • Stallions presented for inspection must be N/N on PSSM1 to be eligible for approval.

  • To submit a (self-executed) PSSM result, a declaration of authenticity must be completed and signed. Make sure you have ticked all the boxes after you have read them! Once you have completed everything and signed the declaration, you can send it together with the PSSM result to: nsvtpssm@gmail.com

  • All mares and foals (as of 2018) are tested at admission and/or inspection. If both parents have already been N/N tested, this is not necessary.

  • All PSSM1 results are processed in our system and published in, for example, passports and inspection booklets, where possible.

  • The result will be communicated to you as soon as it is available and after payment of the invoice. The price list for the genetic tests can be found further down this page.

    * We regularly receive requests via e-mail or via the website from which we do not receive a DNA Sample. It remains the responsibility of the applicant at all times to supply a sample. 

    Do you want to know if your sample has arrived properly? Please send an email to nsvtpssm@gmail.com

    Request PSSM1 test;
    through the online application form or by email nsvtpssm@gmail.com

Further on on this page, under the heading DNA purchase, you will find the necessary information as well as the form to be downloaded.

For more information about PSSM, please visit: www.pssm.eu

Submitting a PSSM result

Download your declaration of authenticity form here or click on this link for completing the form online. NB! This is not a test request form.

To submit a (self-performed) PSSM result, a statement of authenticity must be completed and signed. Make sure you have checked all the boxes after you have read them!
Once you have completed everything and signed the statement, you can send it together with the official test result document (PDF) to: nsvtpssm@gmail.com

We will not process your test result without a fully completed and signed statement of authenticity.

PSSM2 Panel Test

PSSM type 2 / PSSM2
PSSM Type 2, also referred to as PSSM2 is a congenital (genetically determined) chronic muscle breakdown problem that occurs in a variety of horse breeds

Horses with PSSM type 2 do not have the mutation specific for type 1. Previously, PSSM type 2 could only be detected by means of a muscle biopsy (taken from the skeletal muscle of the hamstring; N, Semimembranosis), but now there are several genes responsible for causing PSSM type 2 symptoms.

The American company EquiSeq has found a number of genes that cause PSSM type 2, which makes genetic testing possible. EquiSeq's findings will be published soon and are therefore not yet academically validated, but if desired, they can already be tested for the presence of these genes. We consider EquiSeq's findings important enough to present them on this website. It has already been shown several times that adjusting the management of horses after testing for the presence of these genes has brought about a significant improvement in quality of life.

EquiSeq's research has shown that PSSM type 2 is not a sugar storage problem, but a chronic muscle wasting problem. The genes that cause PSSM type 2 are called semidominant. A horse is affected and therefore more affected if it has 1 copy (for example n/P2 or n/P4), but the symptoms are usually more severe if the horse carries 2 copies of the gene (for example P2/P2 or P4/P4). For now, all genes that cause PSSM symptoms but are not PSSM type 1 are labeled with a “P” plus a number. Found so far: P2, P3 (already renamed MFM), P4, P5 and Px.

PSSM type 2 / PSSM2 – myopathy panel.
EquiSeq has concluded from research that PSSM type 2 is not a sugar storage problem, but a chronic muscle breakdown problem. They have named the genes they identified P2, P3, P4, P8, Px and K1. These genes are called semi-dominant. A horse is affected and thus affected (“has PSSM”) if it has 1 copy (e.g. n/P2 or n/P4), but symptoms are usually more severe if the horse carries 2 copies of the gene (e.g. P2/P2 or P4/P4) or has multiple variants from the panel (e.g. n/P2 in combination with n/P4 or n/P3 in combination with n/Px).

Each variant of the EquiSeq panel is based on a different mechanism, but the symptoms are broadly similar (see: symptoms). Symptoms often only become visible from the age of 7 - 10 years. Often horses become symptomatic after a trigger occurs that causes a negative nitrogen balance in the body. Think of a medical procedure or an injury. Vaccinations are also a possible trigger.

P2 is a mutation of the MYOT gene, a gene that encodes myotilin. This mutation affects the integrity of the Z-disk, weakening and atrophying the affected muscle. In humans, this mutation is the cause of Myofibrillar Myopathy 3 (MFM3). This muscle abnormality is often expressed in adulthood and gives symptoms of Limb Girdle Muscular Distrophy 1A, a muscle disease with the main symptoms of muscle weakness and muscle atrophy in the (control of the) limbs.
P3 is a mutation in the FLNC gene, a gene that encodes filamin C. This mutation affects the integrity of the Z-disk, weakening and atrophying the affected muscle. In humans, this gene is associated with Myofibrillar Myopathy 5 (MFM5). It is a muscle abnormality that is often expressed in adulthood and gives symptoms of Limb Girdle Muscular Distrophy, a muscle weakness and muscle atrophy in the muscle groups in the (control of the) limbs.

P4 is a mutation of the MYOZ3 gene, a gene that encodes myozenin3. Myozenin is a component of the Z-disk that binds other Z-disk proteins and thus this mutation affects the integrity of the Z-disk. This mechanism has already been demonstrated in mice; in humans this could explain hitherto unresolved muscle problems.

P8 is a mutation in the PYROXD1 gene, a gene necessary for the body's antioxidant defenses. This mutation causes, among other things, degradation of the integrity of the Z-disk sarcomeres and the myofibrils or contractile elements, causing muscle weakness and atrophy. In humans, this mutation is associated with Myofibrillar Myopathy 8 (MFM8).

Px is a mutation in the CACNA2D3 gene, which encodes a regulatory subunit of the voltage-gated calcium channels. It affects the process by which motor neurons transmit signals to initiate muscle contraction. This gene is associated with Recurrent Exertional Rhabdomyolysis (RER); the classic muscle contraction or Monday morning sickness, in which the horse can hardly or no longer move, sweats profusely and (in severe cases) has coffee-coloured urine (myoglobinuria). In a less severe form, this can manifest itself in muscle stiffness and/or abnormal gait. Elevated muscle values (CK and AST) are common here. A special characteristic of horses with Px is their sensitivity to stress and its sometimes extreme, explosive expression. The presence of Px can amplify the symptoms of a horse with P2, P3 or P4. It is known that several genes are involved in the expression of RER. Further research is being done on this.

K1 is a mutated version of COL6A3 and has been linked to a disruption in the collagen production of the endomysium, a layer of connective tissue that covers individual muscle fibers. In humans, this condition is known as Bethlem's disease, which is usually included in the group of congenital muscular dystrophies. In horses, it can manifest itself in symptoms that are considered typical for PSSM type 2, such as muscle stiffness, muscle tremors, abnormal gait such as rope walking and reluctance to move forward.

In Europe, the complete EquiSeq panel can be tested at CAG (Center for Animal Genetics)/Generatio in Germany.

EquiSeq's findings have not yet been published and peer reviewed. This process is ongoing and is part of, among other things, the large-scale research that Dr Molly McCue is leading at the University of Minnesota. For this reason, it should be taken into account that medical science, including veterinarians, may not recommend or recognize these tests.

Source: www.pssm.eu

Request PSSM2 Panel test ;
through the online application form or by email nsvtpssm@gmail.com

Information flyer PSSM2 Panel test CAG (English)

www.centerforanimalgenetics.com

ETALON Combi Test

Tinkers come in all shapes, sizes and colors! Much is still unknown due to the unrecorded background. You can now carry out a complete test for only 127.50. Tests are then carried out for the following:

Color tests:

  • Agouti (A)

  • Cream (Cr) & Pearl (Prl)

  • Leopard Complex (LP) & Pattern1 (PATN1)

  • black (E)

  • Dominant Whites (DW1-21)

  • Sabino1 (Sb1)

  • Red/Chestnut (e)

  • Thin (D) & Non-Dun

  • Primitive Markings (nd1/nd2)

  • Silver (Z)

  • Brindle (IP)

  • Gray (G)

  • Splashed Whites (SW1-4)

  • Champagne (CH)

  • Frame Overo/Lethal White (LWO)

  • Tobiano (TO)

For extra fast processing you will be asked to send the hair to our affiliate in France;

AFDT – Le Bancuq – 46250 Marminiac 

health tests

  • Androgen Insensitivity (AIS)

  • Lavender Foal Syndrome (LFS)

  • Cerebellar Abiotrophy (CA)

  • Lethal White Overo (LWO)

  • Foal Immunodeficiency Syndrome (FIS)

  • Lordosis (Swayback)

  • Glycogen Branching Enzyme Deficiency (GBED)

  • Polysaccharide Storage Myopathy (PSSM1)

  • Hereditary Equine Regional Dermal Asthenia (HERDA)

  • Severe Combined Immunodeficiency (SCID)

  • Hyperkalemic Periodic Paralysis (HYPP)

  • Malignant Hyperthermia (MH)

  • Impaired Acrosomal Reaction (IAR)

  • Myotonia (MY)

  • Junctional Epidermolysis Bullosa (JEB1)

  • West Nile Virus (Normal vs. Risk)

  • Junctional Epidermolysis Bullosa (JEB2*)

Application form Etalon combi test

Price list Testing

  • Standard PSSM1 test – 46 euros (CAG) or 55 euros (Laboklin)

  • PSSM2 Panel test (P2,P3,P4,PX,P8,K1) – 320 euros

  • Color test- 29.50 euros

  • Etalon Combitest – 127.50 euros (see above list)

Take DNA

The DNA must be taken by a Vet for an official test result or by yourself if the result is not used for official (Studbook) matters. Via the link below you can download and print the application form for the Vet.
(You will not receive any forms, you must download and print the form yourself)

Pssm test application form 

After the purchase, this can be sent to (including a statement from the DA or studbook consultant);

NSvT Department PSSM
Lambertveen 27
3755 JC Eemnes

We regularly receive requests by e-mail or via the website from which we do not receive a DNA Sample. It remains the responsibility of the applicant at all times to provide a sample. 

Do you want to know if your sample has arrived properly? Please send an email to nsvtpssm@gmail.com

Dutch Studbook for Tinkers

Address data

E: nsvtkantoor@gmail.com 
Whintontlaan 200
3526 KV Utrecht 

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