Skip to main content

What is Muscle Integrity Myopathy (PSSM2)?

Muscle Integrity Myopathy (PSSM2) is form of Exertional Myopathy (link in those words), in which the structure and/or function of the muscle is disrupted.  It is caused by hereditary predisposition and various environmental factors (age, feeding, husbandry). Typical symptoms can include unexplained lameness, muscle stiffness, difficulties with gait changes/coordination, reluctance to move, muscle atrophy and/or difficulty building muscle. Almost any breed of horse can be affected.
Six genetic variants that can disrupt muscle structure and/or function have been identified in horses. These predispose a horse to developing symptoms of exertional myopathy.


Get more information

Possible Symptoms of Muscle Integrity Myopathy (PSSM2)

  • Unexplained lameness

  • Training intolerance / reluctance to move

  • Pain-related behavioural changes

  • Muscle atrophy


Test now for Muscle Integrity Myopathy (“PSSM2”) and finally get clarity on associated symptoms.

Our Genetic Test

Order the Muscle Integrity Myopathy 6-Variant-Panel-Test (‘PSSM2-Test”).


The following genetic variants are included, which pose a high risk for the development of muscle integrity myopathy symptoms in horses:

  • P2: Myotilinopathy
  • P3: Filaminopathy
  • P4: Myozenin-3-Myopathy
  • Px: CACNA2D3-Myopathy
  • P8: PYROXD1- Myopathy
  • K1: COL6A3-Myopathy


Download the flyer:

It is generally not possible to cure genetic disorders; however, with optimized management the currently known genetic variants can often be compensated for with specialized feeding and exercise protocols, often allowing the horses to enjoy a normal life with minimal/manageable symptoms.


Get more information

For horse owners

For Veterinarians

More information

More information on Muscle Integrity Myopathy (PSSM2)

Read more »

Our MIM 6-Variants-Test ("PSSM2")

Read more »


  • questionaire on MIM (PSSM2)
  • studies
  • research
Read more »


  • Download Flyer