Table 1.

Nucleotide Content Differences (%) for Introns >2047 nt Versus Introns 60–127 nt Long

		D − 32 to D − 1	D+1 to D+32	A − 32 to A − 1	A+1 to A+32
Intron before	A	1.99	1.62	−1.75	2.48
	C	−0.93	−0.36	−0.57	−0.24
	G	−1.59	−0.72	−0.59	−2.11
	U	0.54	−0.54	2.91	−0.13
Varied intron	A	2.32	0.42	−4.31	1.00
	C	−0.57	0.39	1.26	0.40
	G	−0.92	0.51	−0.54	−0.62
	U	−0.83	−1.33	3.59	−0.78
Intron after	A	−0.33	1.11	−1.61	−0.71
	C	1.31	−0.68	1.75	1.14
	G	0.02	0.67	−0.24	0.32
	U	−1.00	−1.11	0.10	−0.76

Bold difference values have p > 0.99 significance by a two-tailed t-test using the observed standard deviations in nucleotide content over the 32-nt ranges. These differences were also significant by the non-parametric Mann-Whitney test, which also showed the increase in U for the varied intron (D − 32 to D − 1) to be significant (p > 0.99).