Table 2.

The spacer sequence C(A/T)G is detected at over 41% of ERα-bound ERE sequences. Shown are the ten most common ERE half-site and spacer sequences from 646 EREs detected within high-confidence ERα-bound loci. Over 41% of the spacer sequences were CAG or CTG whereas the expected prevalence of C(A/T)G spacers would be 3.1% if these residues were random nucleotides. Similar findings were noted when repetitive element EREs were excluded from the analysis (Table S4).

5′ ERE half-site			Spacer Sequence			3′ ERE half-site
Seq.	#	%	Seq.	#	%	Seq.	#	%
AGGTCA	150	23.22	CAG	150	23.22	TGACCT	163	25.23
AGGTTG	65	10.06	CTG	116	17.96	TGAGCC	42	6.50
GGGTCA	56	8.67	GGG	17	2.63	TGCCCT	36	5.57
AGCTCA	35	5.42	GAG	15	2.32	TGAGCT	36	5.57
ATGTCA	31	4.80	GCC	15	2.32	TGACCC	35	5.42
AGGGCA	30	4.64	AGG	14	2.17	CAACCT	34	5.26
AAGTCA	19	2.94	GGC	14	2.17	TGACCA	23	3.56
AGGTTA	15	2.32	CAC	12	1.86	TGACAT	22	3.41
AGGCCA	12	1.86	GGT	12	1.86	TGACTT	19	2.94
TGGTCA	12	1.86	AGC	11	1.70	TAACCT	17	2.63