Table 1.

Average correlation across all probes of normalised methylation measurements between relative pairs

Relationship	Pairs (n)	Correlation	Expected a
MZ twins	67	0.200	h2
DZ twins	111	0.109	h2/2
Siblings	262b	0.090	h2/2
Parent-Offspring	362b	0.089	h2/2
Mother-Offspring	190	0.097	h2/2
Father-Offspring	172	0.085	h2/2
Parent-Parent	58	0.023	0
Unrelated	187,331b	-0.002	0

^aThe expected correlation under an additive genetic model with a heritability of h².

^bThis is the number of quasi-independent pairs as some individuals are represented in multiple pairings.