every breed animal on the planet that has a lot of white has problems with deafness, blindness etc. Don't know why, and don't know why there's not any yet in the icelandic breed... unless they eat them? SOme say the SD gene that results in blindness is breed specific, that it comes from one particular horse in the RMSH breed, but the RMSH blood is all throughout the TWH and RH breeds since they had open books for a while and RMSHs were gaited so pass gait commission registration. I know a twh herd with the sd gene and eye problem. so the sd thing, i dont know, but if I had splash white or overo icelandics i would just be on the safe side and use the same breeding rules people with other white animals use. not sure what it is tho! I just know my friend who breeds aussies does not breed a blue merle and a blue merle to get blue merle. Or it will cause deafness and eye problems. He doesnt have any deaf or blind in his breeding program, but just knows the genetic predisposition. something about blue eyes too... at the auction recently a man out front was selling a little of the most incredible cattledogs, just gorgeous. I know three people locally who bought one, (we have one and they are popular with horse people so word got around) and of the three, two were deaf.
The lethal white syndrom is not in EVERY overo horse bred and you can breed some overos to overos without getting lethal white. And I have often wondered since it was a small gene pool that icelandics have overo and splash and blue eyes, but not the lethal white gene,( or deafness or blindness gene ) but how do things naturally occur? I dont see what it hurts to pay attention to everyday genetics unless you are like the backyard dog breeder who just puts two pretty ones together. as for color breeding, it has ruined more than one breed. completely. not just horses but dogs. Janice -- even good horses have bad days sometimes.
