Appendix B.

Monoamine oxidase A genotype differences in study variables for African American and Caucasian men

Racial Group	1. MP at Age 1.5	2. HAB at Age 10	3. ARG at Age 10	5. VA at Age 17	6. OAR in EA	7. AB at Ages 20 and 22
1. AA men
L-MAOA	M = 1.21, SD = .49	M = 5.22, SD = 1.99	M = 2.15, SD = 1.92	M = 34.55, SD = 11.50	M = 0.20, SD = 0.29	M = 10.95, SD = 10.59
H-MAOA	M = 1.09, SD = 0.23	M = 5.46, SD = 1.64	M = 1.96, SD = 1.53	M = 36.54, SD = 10.28	M = 0.20, SD = 0.28	M = 7.45, SD = 5.23
t-test score	t (46.70) = 1.38,	t (53) = −0.49,	t (53) = 0.39,	t (68) = −0.77,	t (74) = 0.04,	t (44.67) 1.74,
	p = .174	p = .624	p = .695	p = .446	p = .970	p = .090
95% CI	[−0.06, 0.31]	[−1.23, 0.74]	[−0.75, 1.12]	[−7.19, 3.20]	[−0.13,0.13]	[−0.57, 7.57]
2. CA men
L-MAOA	M = 1.10, SD = 0.33	M = 5.17, SD = 1.75	M = 1.83, SD = 1.54	M = 34.57, SD = 9.10	M = 0.11, SD = 0.23	M = 11.60, SD = 7.02
H-MAOA	M = 1.14, SD = 0.33	M = 3.89, SD = 2.09	M = 1.11, SD = 1.54	M = 33.46, SD = 7.95	M = 0.07, SD = 0.17	M = 10.12, SD = 7.94
t-test score	t (99) = −0.55,	t (84) 2.82,	t (84) 2.06,	t (99) = 0.61,	t (46.09) = 1.04,	t (98) 0.88,
	p = .584	p = .006	p = .043	p = .544	p = .304	p = .380
95% CI	[−0.18, 0.10]	[0.38, 2.18]	[0.02, 1.42]	[−2.49, 4.69]	[−0.04, 0.14]	[−1.85, 4.80]

Note: Degrees of freedom (df) that include decimals indicate t-tests that violated the homogeneity of variance assumption, which we corrected with the use of Welch t-test. MAOA, Monoamine oxidase A genotype; MP, maternal punitiveness; HAB, hostile attributional bias; ARG, aggressive response generation; VA, violent attitudes; OAR, official arrest record; EA, early adulthood; AB, antisocial behavior; AA, African American; CA, Caucasian American.