Genetics defines the condition and you might want to consider contacting NOAH.
National Organization for Albinism and Hypopigmentation -- contact information is available using the 'Search' option.
If your husband has been evaluated by an ophthalmologist (MD), there should be patient information provided by the physician. I would not consider an optometrist as being qualified.
Another specialty that you might want to consider is a geneticist that can provide a better understanding of the condition. It is not common but a medical center with a residency in ophthalmology will have the most up to date information.
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