Table 3.

Effect of COMT haplotype on DNA methylation in the whole group. Data is reported as mean (standard error) of both assessments. F-test and p-values refer to the univariate test of the Linear Mixed Model

	Haplotype
DNA methylation (%)	High COMT activity	High-intermediate COMT activity	Intermediate COMT activity	Intermediate-low COMT activity	F	p
MB-COMTa	2.79 (0.34)	2.88 (0.18)	2.51 (0.29)	2.52 (0.56)	0.557	0.646
MB-COMTb	1.43 (0.21)	1.80 (0.12)	1.45 (0.19)	1.51 (0.33)	1.73	0.170
MB-COMTc	2.15 (0.36)	2.36 (0.19)	2.30 (0.37)	2.84 (0.56)	0.355	0.785
MB-COMT mean	2.25 (0.27)	2.48 (0.15)	2.21 (0.26)	2.41 (0.41)	0.495	0.687
S-COMTa	54.42 (1.57)	60.42 (0.74)	66.00 (1.41)	67.43 (2.52)	11.539	< 0.001*
S-COMTb	91.95 (0.64)	93.09 (0.31)	94.80 (0.57)	95.97 (1.01)	5.879	0.001*
S-COMTc	91.71 (0.44)	92.52 (0.22)	92.15 (0.39)	91.47 (0.70)	1.573	0.202
S-COMT mean	78.21 (0.64)	80.91 (0.30)	83.02 (0.58)	83.54 (1.03)	11.580	< 0.001*