Somalian children living in Minnesota have a higher rate of autism compared to whites and non whites. They have also noticed this in Stockhom as they also have a lot of Somalian immigrants. Researches have found "The increased prevalence remained and was now between four and five times higher in children of Somali background. A clinical observation was that more than 80%, in addition to autism and learning disability, had a profound hyperactivity." http://onlinelibrary.wiley.com/doi/10.1111/j.1469-8749.2010.... People have hypothesized vitamin D could be contributing to this as having darker pigmentation makes it harder to absorb sunlight.