Table 1.

2 × 2 contingency table obtained by classifying genes into 2 categorical variables. The letters denote the number of genes for a given category (e.g., “a” denotes the number of retained genes annotated with the tested GO category)

	GO	Not-GO	SUM
Retained	a	b	a + b*
Not-retained	c	d	c + d
Sum	a + c	b + d	N = total number of genes
			=29,550 (across 7 chromosomes)

*equal to 1302 and 6972 for candidate WGD-derived paralogs and tandem gene duplicates, respectively