A class of human exons with predicted distant branch points revealed by analysis of AG dinucleotide exclusion zones

Table 1 Analysis of the curve pairs from Figure 2

Dinucleotide	C	EZ₂	EZ₁	χ²
AA	218	148	211	26.8
AC	143	149	129	2.7
AG	100	148	279	116.0
AT	186	149	173	3.9
CA	98	151	187	8.6
CC	227	151	161	0.7
CG	1,039	148	150	0.0
CT	96	150	86	27.3
GA	120	158	211	17.8
GC	186	148	173	4.2
GG	203	150	200	16.7
GT	111	149	153	0.1
TA	292	149	185	8.7
TC	131	150	77	35.5
TG	74	149	123	4.5
TT	177	148	157	0.5

Shown is an analysis of the curve pairs from Figure 2 comparing the tails of the modified exclusion zone (mod-EZ)₁ and mod-EZ₂ distributions for each dinucleotide above a cutoff (C). This cutoff is the point at which the mod-EZ₂ tail contains close to but no fewer than 148 entries (in order to have analysis equivalent to the AG case). The EZ₂ and EZ₁ columns give the observed numbers of entries above C, and the χ² column gives the associated χ² value. Note that, with one degree of freedom, a χ² value of 4 gives a P value close to 0.05; thus, χ² values < 4 are not statistically significant.

ISSN: 1474-760X