Table 3. Correlation of methylation with gene expression based on island context.

Matched CpGs by CGI context	total	positively correlated	negatively correlated	ratio neg/pos	p-value
Island	724	325	399	1.23	0.00002
Shore	2060	689	1371	1.99	0.09809
Open Sea	2639	1012	1627	1.61	<0.00001

The matched CpGs are sorted by their island context and then based upon the direction with which gene expression correlated with methylation. The p-value comes from a test of proportions on the Spearman rank correlation coefficient obtained for the ratios of positively and negatively correlated CpGs at each location.