Table 3

Significant main effect of SNPs and age × SNP interactions in the entire sample (n = 240)

Region	Main effect of SNP		Age × SNP interaction

	Cohen d	Statistics	Cohen d	Statistics	R²
rs2896218
Left hemisphere (mean thickness)	AA v. GG: 0.038	F = 5.32	Age × AA: −0.316	F = 5.06	0.27
	AG v. GG: 0.175	p = 0.006	Age × AG: −0.475	p = 0.007
			Age × GG: −0.127
Right hemisphere (mean thickness)	AA v. GG: 0.034	F = 5.38	Age × AA: −0.300	F = 4.78	0.26
	AG v. GG: 0.174	p = 0.005	Age × AG: −0.459	p = 0.009
			Age × GG: −0.122
Right middle-posterior part of the cingulate gyrus and sulcus (posterior midcingulate cortex)	AA v. GG: 0.152	F = 10.33	Age × AA: −0.273	F = 9.71	0.24
	AG v. GG: 0.283	p < 0.001^**	Age × AG: −0.437	p < 0.001^**
			Age × GG: 0.008
Right orbital gyri	AA v. GG: 0.098	F = 4.31	Age × AA: −0.320	F = 5.27	0.22
	AG v. GG: 0.183	p = 0.015	Age × AG: −0.386	p = 0.006^*
			age × GG: −0.036
Right superior segment of the circular sulcus of the insula	AA v. GG: 0.090	F = 3.31	Age × AA: −0.222	F = 2.30	0.14
	AG v. GG: 0.161	p = 0.038	Age × AG: −0.297	p = 0.10
			Age × GG: −0.042
Right triangular part of the inferior frontal gyrus	AA v. GG: 0.025	F = 4.10	Age × AA: −0.223	F = 4.40	0.17
	AG v. GG: 0.143	p = 0.018	Age × AG: −0.380	p = 0.013
			Age × GG: −0.096
Right superior temporal sulcus (parallel sulcus)	AA v. GG: −0.017	F = 6.65	Age × AA: −0.286	F = 4.91	0.27
	AG v. GG: 0.149	p = 0.002^*	Age × AG: −0.465	p = 0.008^*
			Age × GG: −0.199
rs6950765
Left hemisphere (mean thickness)	CC v. GG: −0.110	F = 6.79	Age × CC: −0.057	F = 6.01	0.29
	CG v. GG: 0.190	p = 0.001	Age × CG: −0.484	p = 0.003
			Age × GG: −0.344
Right hemisphere (mean thickness)	CC v. GG: −0.107	F = 6.94	Age × CC: −0.050	F = 5.91	0.27
	CG v. GG: 0.196	p = 0.001	Age × CG: −0.471	p = 0.003
			Age × GG: −0.329
Right middle-posterior part of the cingulate gyrus and sulcus (posterior midcingulate cortex)	CC v. GG: −0.229	F = 14.48	Age × CC: 0.089	F = 13.97	0.27
	CG v. GG: 0.184	p < 0.001^**	Age × CG: −0.454	p < 0.001^**
			Age × GG: −0.301
Right orbital gyri	CC v. GG: −0.157	F = 7.04	Age × CC: 0.016	F = 7.09	0.23
	CG v. GG: 0.132	p = 0.001^*	Age × CG: −0.396	p = 0.001^*
			Age × GG: −0.334
Right superior segment of the circular sulcus of the insula	CC v. GG: −0.151	F = 6.26	Age × CC: 0.032	F = 5.97	0.16
	CG v. GG: 0.121	p = 0.002^*	Age × CG: −0.333	p = 0.003^*
			Age × GG: −0.234
Right triangular part of the inferior frontal gyrus	CC v. GG: −0.061	F = 6.27	Age × CC: −0.048	F = 5.00	0.18
	CG v. GG: 0.193	p = 0.002^*	Age × CG: −0.379	p = 0.008^*
			Age × GG: −0.235
Right superior temporal sulcus (parallel sulcus)	CC v. GG: −0.075	F = 8.01	Age × CC: −0.125	F = 6.07	0.27
	CG v. GG: 0.215	p < 0.001^**	Age × CG: −0.486	p = 0.003^*
			Age × GG: −0.315

FDR = false discovery rate; SNP = single nucleotide polymorphism.
Model: Cortical thickness of specific brain region = β₀ + β₁ “SNP” + β₂ “age × SNP” + β₃ “age” + β₄ “sex” + β₅ “full-scale IQ” + β₆ “handedness” + β₇ “intracranial volume” + ɛ. Findings for the main effects of SNP and age × SNP interaction for rs2896218 and rs6950765 are summarized above. For the 9 cortical regions,
↵* q_FDR < 0.05,
↵** q_FDR < 0.01.