I want to point out the following fact. English is a schizophrenic language in that there is a huge discrepancy between how words are written and how words are pronounced, and when facing a new written word, there is usually no rule to know how it should be pronounced. That can confuse the brain.
Some personal anecdotes. My first language is not English. I've been living in the UK for years though, and I can tell that the more fluent I've become in English, somehow the more 'dyslexic' I've become (especially when writing). I know two properly bilingual people who have no problem of any kind in my native language, but are classified as dyslexic when it comes to English. And they're both quite intelligent and cultivated.
I suspect that dyslexia has something to do with the English language, not the people. (How many non-english speaking dyslexics are there? Does anyone have any numbers/figures?)