I have just had a litter of english bulldogges. I have recently just taken them in for their first set of shots. While examining the pups, the vet informed me that the pups had Congenital Nystagmus. Their eyes were twitching. I'm wondering if this can be cured? What are the causes? Is it genetic? Is ther anything I can do to prevent this in the future? What are the long term effects for these pups and how will it effect their lives? Thanks for any help or guidence you can give me.