Figure 1.

The advantages of using a reference to highlight regional biases. Figure 1A shows log₂ spot ratios at a constant intensity. Red corresponds to a log ratio of greater than 0.5; yellow to a log ratio of 0, and green to a log ratio of less than -0.5. Figure 1B shows the log₂ ratios for the same slide relative to the averages of the log₂ ratios across all the slides. Figure 1C shows the log ratios for the same slide after background subtraction. The right portion of the bottom row in each print-tip group was spotted with buffer only.