Other research on this involves multi-lingual families, where the amount of literacy in the home is unclear. Some schools have children read books repeatedly in school so the child can take the book home and read to the family at the emergent or conventional reading level. For literacy development you need to have started even earlier with these children and catch them as soon as possible, but you don't do much differently in teaching reading. Different regional pronunciations can make trouble with curriculum materials, for example hearing sounds that are different in some dialects and the same in others. Curriculum won't help with this.
Teacher preparation is important.
There are two issues here. One explanation is the sound differences. Another explanation is that dialect is not neutral. We think that some dialects are better, that our own are better, and there is social stigma involved. This subject requires optimal teacher preparation for teachers to have high expectations for all students.