Fig. 4.

Longitudinal changes and environmental influences in methylation levels

(A and B) The longitudinal changes in CD3Z (A) and VHL (B) methylation levels from blood samples taken at two time points (P1 and P2, where P1 is the earlier point) in SLE patients (n = 16) are shown. (C–H) Difference in methylation level between pairs of monozygotic (MZ; C and F; n = 22), dizygotic (DZ; D and G; n = 15) and SLE-discordant MZ (DMZ; E and H; n = 8) twins were analysed. The MZ and DZ twins were controls without SLE. Twin sisters 1 and 2 (MZ1 and MZ2 or DZ1 and DZ2) were assigned randomly.