Two Leopard Complex (LP) genes & Congenital stationary Night blindness (CSNB)

A horse with two copies of the Leopard Complex gene, a huge asset in the breeding world of Appaloosas because they will pass on one LP gene 100% of the time, thus their progeny will be Characteristic. Additionally, LP/LP horses without question will be affected by Congenital stationary Night blindness (CSNB).

Over the years, we’ve had four Appaloosas here at the stud, Easter, Blanc, Blu, and Ru. They all have one thing in common, they are homozygous for the Leopard Complex (LP) gene which also means they have Congenital stationary Night blindness. Not a taboo subject for us, knowledge is key for the safety of the horses and their owners.


Redheart Cateaster


Redheart Regal


DFR Patahas Redheart

Redheart RU Chubarry

CSNB doesn’t prevent a normal life at all…

Here is a link to our YouTube video

2 replies
  1. Mirella Placidi
    Mirella Placidi says:

    Thank you for sharing – I am investigating whether my Appaloosa is LpLp as his behaviour changes in dim light i.e. as we come out of summer into Autumn – if I know for sure I can adjust my training schedule – but notes and video share were very ujseful

    • Paula Cooper
      Paula Cooper says:

      Hello Mirellla,

      In reality, if your horse is LP/LP it will have Congenital Stationary Night Blindness (CSNB).
      To be 100% certain, collect by pulling 30-40 mane and/or tail hairs from your horse, ensuring the actual root of the hair is attached.
      Place the sample in a zip-lock bag or envelope that is labelled with the horse’s name. Do not send wet hair especially in a zip-lock bag (warmth & moisture might give bacteria an opportunity to grow which could damage the DNA).
      Complete a submission form and mail the sample.
      Forms, payment and details are available on any of the labs listed below on our “Interesting Link section” at the bottom pf our Web page.
      Etalon Diagnostics, Animal Genetics UK and Animal Genetics USA.
      It is not an issue, nor is it a problem if your horse is confirmed with CSNB but for yours’s and your horses safety and anyone dealing with your horse it is important to KNOW!


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