Array CGH using random prime (A, C, E) versus DOP (B, D, F) amplification with 50 ng of input DNA. Normal genomic male versus female DNA is shown in A and B, whereas DNA from a fresh-frozen breast tumor versus female reference is shown in C and D, and results from the same tumor that was formalin-fixed and paraffin-embedded is shown in E and F. Log2 ratios for each BAC are plotted according to chromosome position.