TABLE 2.

CCAATCA and derivative motifs show significant association with DSB hotspots in the genome

Motif	Total number in genome	Number within hotspots	Fraction within hotspots (see text)	Fractional enrichment within hotspotsa
CCAAT	30,442	3086	0.101	−0.03
YCAATC	14,147	1528**	0.108	0.04
CCAATC	6413	679*	0.106	0.02
DCCAATC	4237	469**	0.111	0.06
VDCCAATC	2637	295*	0.112	0.08
DCCAATCA	1114	134**	0.120	0.16b
CCAATCA	1408	172**	0.122	0.17b
DCCAATCANND	887	112**	0.126	0.21b
SVDCCAATC	938	121**	0.129	0.24b
CCAATCANND	1119	145***	0.130	0.25b
VDCCAATCA	652	87**	0.133	0.28b
YSVDCCAATC	479	67**	0.140	0.34b
VDCCAATCANND	524	76***	0.145	0.39b
SVDCCAATCA	218	33**	0.151	0.46b
SVDCCAATCANND	170	30**	0.176	0.70bc
YSVDCCAATCA	100	18**	0.180	0.73b
YSVDCCAATCANND	83	16**	0.193	0.85bc
ATGACGTd	285	63***	0.221	1.12

*P < 0.05; **P < 0.01; ***P < 0.001; probability that the number of motifs falling within hotspots is due to chance. Probabilities are based on the binomial distribution formula with 10.4% of the genome found within DSB hotspots (see text).

^a(Observed fraction –0.104)/0.104.

^bP < 0.05; χ² probability that the increased fraction of the indicated motif found within hotspots is not different from the five-base CCAAT motif.

^cP < 0.05; χ² probability that the increased fraction of the indicated motif found within hotspots is not different from the seven-base CCAATCA motif.

^dThe M26 motif is provided for comparison.