Summary of the repression of miniwhite gene expression by human PREs in all the transgenic flies.

Eleven potential human PRE elements were individually tested for their suppression of white gene expression, judged by fly eye color with the corresponding transgene; pair-sensitivity and de-repression by ph401 mutation. The eye color was classified to eight levels from −4 to +4, where −4 was the palest and +4 the darkest. On average 5–6 independent lines were tested for each transgene and the results were summarized. The strongest group contains SLC, NPR, LGR and NeuD; the intermediate group is consisted of A3, XKR, PITX and BCAN; and the weakest group includes PDE, UNC and A13. BRG serves as a control.