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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Our goal is to give members a way to check pedigrees for DNA results. The more horses we enter the better answers we provide for our members. We've set a goal of 100,000 horses for 2014.
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Members Speak Out

Im Tee Totally Tenacious -
aka Kosta - 2012 chestnut colt (to be gelded)
The resulting foal from the above mare who has also tested positive. He will be gelded & remain with me. As I do... Lyn Watt @ 2013-10-14, 20:09
My colt is 4 months old right now, we got him at 3 months old. PSSM hasn't effected him to bad as of yet but we have had to keep him on a strict diet to hopefully keep him from being one of those hors... Tricia @ 2013-10-14, 17:52
PSSM - As odd as it sounds PSSM first sounded like a solution to me. I'd been experiencing problems with a gelding under saddle and was hopeful that PSSM might be at least some kind of reason or answe... Olivia Dixon @ 2013-10-11, 17:56
Like it Like That - aka Posh - 2009 liver chestnut QH mare.
Her dam tested negative, so we knew it was her sire that was positive & he has since been tested positive.
She didn't really p... Lyn Watt @ 2013-10-14, 19:29
Im Tee Totally Original (iiu) - aka Tiya - 2005 chestnut QH mare. (Dam tested Positive) She was the start of my search & how I found PSSM. She tied up when I went to bring her back into work, after l... Lyn Watt @ 2013-10-14, 19:33

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.

Tested Horses For Sale

With your Bridge Membership you can list your BRIDGE Registered Five Panel N/N tested horses for free, for as long as you own them.  Just click the link at the side to access the listed horses for sale.  There are multiple searches you can perform and you can also create a favorites list (Wish List) for your self when you are a registered BRIDGE Member.

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 946 FivePanel N/N Horses in our MD

  We have 3761 PSSM N/N Horses in Our MD

  We have 1073 PSSM pos horses in our BPD

  NEW! We have 40 PSSM2 Pos in our BPD

  We have 2046 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 3978 HYPP pos horses in our BPD

  We have 383 HERDA pos horses in our BPD

  We have 175 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.





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