TABLE 3

Upstream 5′ flanking regions of operons are shorter than most nonoperon genes

Expression categorynMedianaMeanaSDSignificanceb
First genes in operons1,1067631,8662,990A
Nonoperon germline1,6548661,9332,875AB
Nonoperon spermatogenesis1,1859852,1743,230B
Nongermline or no expression data13,9471,5363,1024,093C
  • a Length in base pairs.

  • b Gene categories with different letters are significantly different with Tukey's honestly significant differences, accounting for the effects of gene density and chromosomal location (supplemental Table 1).