We own a 1 year old APHA stud colt and lately he has started getting a lot of white showing up on his tail head and fleks of white near his flank and belly... it almost looks like roan but he's DNA tested negative for roan but was never tested for rabicano. He is also homozygous for dun and is an overo but I don't think this can be caused by overo. He has never had these white spots on his tail and never had these white hairs near the belly and only recently developed them when he shedded out this summer. I don't know alot about rabicano so that's why I'm posting here does anyone know if this could be rabicano coming in? Will also be DNA testing to make sure but just trying to guess at the moment

He will be 2 years old on March 29th if that helps

Looks sabino!

Looks a bit like Sabino to me, BUT he may just be a super chromed up colt. Both my 2 year old and yearling are super chromed up, and sometimes it becomes more as time goes on

It looks like rabicano - but it might be caused by the sabino / W mutation. I don´t think you can gene test for rabicano by now - but you can test for sabino/ white spotting. Do you know if his parents have any tested white spotting patterns?

I am very curious if the white will increase when the colt gets older. My gelding is a rabicano and compared to now at 9yo he was almost plain in his first years ;)

His mom is a red roan overo no Sabino no rabicano and his dad is a red dun no white

Etalon has a bunch of info on different random white mutations! I recommend checking out their website for more info

Something like this..

W35, or "Holiday White"

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White markings can cause white ticking which can appear at any point in time :) I'd assume it's just ticking from the overo

So I know a horse that has this exact same thing! He's a chestnut OTTB (16yo) and he's been getting more white flecked as he ages according to his owner! Since you, Cali, said it was ticking from Overo, what could it be cause by in this case?