Sounds like the problem might be with those who are selected to identify the "gifted" students. I am less interested in racial correlations to being identified as "gifted" and more interested in attributes such as whether the student is from a two-parent household, whether they are considered poor, whether they attend a local school or are transported to one outside of their neighborhood, etc. I suspect that we lose out on identifying many gifted children because issues at home and mere survival interfere with their ability to grow and develop academically.