Just can't imagine that such a combination as *Rashad and *BEB would uniquely produce the problem, especially when she was bred to other unrelated stallions (Faarad, Bel Gordas, Ansata El Salim as well as Tibor the General and Alcibiades-the last two do have *Rashad, the other 3 do not) and still produced it.
I don't recall saying that cross uniquely produced the problem to the exclusion of other crosses, simply that they did see a problem with that cross. Since I never worked for Richard, I'm not in a position to argue with someone who did.
*BEB's fall in the shipping crate would be in keeping if she suffered from the condition but since I never saw her and since many, many people never comprehend the ataxia even seeing it for years, I must hold firm to my belief that *BEB and her sisters are the only source.
Then that suggests it was a more recent random mutation closely linked to their pedigree or they are, for whatever reason, producing foals with a strong predisposition for the problem.
I would be more than happy to entertain other genetically inherited theories regarding this condition. Not trying to be hard headed here but more than 20+ years of experience with it has solidified my opinion. And we did supplement with Vit. E/Selenium toward the end of breeding this line, even giving shots to the babies and the mothers but in the end it didn't stop the ataxia.
Until the documentation can be put together to see the common points for all of the reported cases, there is no way of knowing if what everyone is seeing is actually the same disorder or if other issues also coming into play. For example, CA is also suspect for some of the ancestral horses in some of these pedigrees - so that shouldn't be completely ruled for every case. And, not all cases will necessarily appear or respond the same way. I don't think anyone has said that vitamin E is a cure all for it, rather that there is a suspect link in some neurological conditions and in some cases of neurological problems, it has helped. Until a determination can be made for what the BeB Hop actually is, there are limits for how much can be known. Some people feel that it could be EDM or ND, others feel that it isn't. In the end....it is all theory right now.