Summary of the general steps involved in implementing the MDR method. "High-risk" are labeled G1 and "low-risk" are labeled G0 constructing a new one dimensional attribute with G0 and G1. This list of attributes includes the flanking positions ten nucleotides long in both the 3' and 5' direction from the SNP site. Each position has four levels (A, C, G, T) or alternatively two levels (purine, pyrimidine) while the class has two levels (0, 1) that codes for controls and cases. A) illustrates distribution of cases (left bars) and controls (right bars) for each of the four possible classes of attributes. The dark shaded cells have been labeled 'high-risk' using a threshold of T = 1. The light-shaded cells have been labeled 'low-risk'. B) illustrates the distribution of cases and controls when the two functional positions are considered jointly, it is the distribution of cases and controls for the new single attribute constructed using MDR.