What is PSSM1?

There are many scientific definitions of PSSM1 on the internet and if you are interested in the technical definition we invite you to search it out on the internet. 


In our attempt to keep things simple we offer this definition.  PSSM1 is a genetic disease found in many breeds of horses.  It originated in the draft breeds but has become very common in many popular Quarter Horse lines as well.  PSSM is particularly devastating in the Quarter Horse lines because it is still being bred forward, because most people haven't heard of it and because it can so drastically affect an affected horse''s everyday behavior.


Many PSSM1 affected horses are labelled as lazy, difficult, hard to handle, moody, hot or as "just needing a job".  Alot of these behaviors can be cleared up or vastly diminished in many cases by a change of diet.  PSSM horses cannot process sugary foods, among the most commonly fed is oats.


By becoming a BRIDGE member and having access to our online database of genetically tested and suspected horses and the ability to order reports you can quickly check to see if your horse has horses in it's pedigree that indicate that you should be testing your horse.  The genetic test for PSSM was only publicly offered at an affordable price starting in Spring of 2013 so as more and more horses get tested, more and more results will be available in our database.


If in doubt we recommend testing all horses, but the online database and especially the reports can really shed light on your horse's bloodlines.


You can also use our Symptom Checker in the "What Are The Symptoms" link under PSSM1 - Genetic Diseases or just CLICK HERE


What Do You know About PSSM?
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We Need Your Membership

Your nominal membership will help show support for our grassroots cause of raising awareness about genetic diseases in horses.  You've spent $25 dollars in a lot worse ways.  With everyone's help by purchasing a membership and listing their tested horses we hope to rapidly increase awareness to the point where everyone purchasing is making an informed decision.  If you think the genetic diseases aren't so bad and you don't mind purchasing afflicted horses, more power to you, they need homes too - we would just like everyone to be aware of what they are purchasing and hopefully to slow the breeding of affected horses.

Custom Sidetabs


  Color Codes

  E = black  e = red

  For all other color codes lowercase is considered to be N or negative

  eg G/g is one Grey Gene  g/g is no grey genes and G/G is two grey genes

  CR = Cream

  RN = Roan

  DN = Dun

  CH = Champagne

  PRL = Pearl

  Z = Silver

  A = Agouti



   Clear /Grey - info unknown or not entered yet

   Amber - pos parent or pos offspring or pos sibling

   Yellow - suspected

   Blue - highly suspected

   Red - Is Tested or is known Positive

   Dark Purple - double positive

   Light Red - Positive parent & Positive offspring

   Green - Tested or Known Clear

   Light Green - Likely negative

Disease DATABASE Codes

  N/N - no copies of the gene
  PO - Pos offspring 
  PP - Has a Pos parent 
 PS - Pos Sibling 
  PPPO - Pos parent & Pos offspring
  S - Suspected

  PSSM = P1 - 1 Pos Gene, 1 unknown    N/P1 - 1 Pos Gene     P1/P1 - 2 Pos Genes

  HYPP = H - 1 Pos Gene, 1 unknown      N/H - 1 Pos Gene       H/H - 2 Pos Genes

  HERDA = HRD - 1 Pos Gene, 1 unknown   N/HRD - 1 Pos Gene   HRD/HRD - 2 Pos Genes

  MH =1 MH Gene,1 unknown   N/MH - 1 MH Gene     MH/MH - 2 MH Genes

  GBED = GBD = N/GBD - 1 Pos Gene (GBD/GBD is lethal)




  Extra Info About our Database

  We have 1056 FivePanel N/N Horses in our MD

  We have 3953 PSSM N/N Horses in Our MD

  We have 1119 PSSM pos horses in our BPD

  NEW! We have 52 PSSM2 Pos in our BPD

  We have 2067 untested horses with a Pos PSSM parent
  NEW! We have 100 untested horses with a pos Full Sibling

  We have 323 PSSM suspect horses in our BPD

  We have 4009 HYPP pos horses in our BPD

  We have 407 HERDA pos horses in our BPD

  We have 190 GBED pos horses in our BPD

  We have 12 MH pos horses in our BPD

  These numbers are updated Monthly!  Please Register your Disease Positive Horse (FREE) so we can grow this young database & give people information to make good decisions.





  Join our Aged Horse PSSM Testing Promotion!
    Check bottom left Corner of the Site for BRIDGE PROMOS!

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