highly significantp < 0.00001
The mean behaviour of these groups of genes in response to heat shock displays a highly significant positive correlation (Pearson r = 0.312, p < 0.00001, Spearman r = 0.314, p < 0.00001; electronic supplementary material, file S2), such that those mRNAs corresponding genes more distant from transcription initiation sites increase in abundance while those close to transcription initiation sites decrease.