Figure 2

Distribution of the number of genes for which the probe-sets detected expressed transcripts. For each gene a probe-set with a variable number of probes (5 or 10) was designed. The number of probes within the probe-set with signal above background was counted and four categories are shown: (None) - when none of the probes displayed signal above background; (Single) - when a single probe in the probe set showed signal above background; (Variable) when more than one but less than the total number of probes in the probe set had signal above background; and (All) when all probes had signal above background.