Examining impulsivity as an endophenotype using a behavioral approach: a DRD2 TaqI A and DRD4 48-bp VNTR association study

Table 6 Performance on Measures of Impulsivity by Genotype and Significance values

	DRD2					DRD4					Interaction
	A1+		A1-		p	L+		L-		p	p
	Mean	SE	Mean	SE		Mean	SE	Mean	SE
BIS Attentional Impulsivity	16.49	0.41	17.58	0.32	0.171	17.12	0.50	16.92	0.2975	0.791	0.223
BIS Motor Impulsivity	21.19	0.39	22.17	0.38	0.131	21.68	0.49	21.59	0.3311	0.933	0.510
BIS Non-planning Impulsivity	25.22	0.46	25.56	0.40	0.783	25.08	0.46	25.38	0.3807	0.636	0.660
BIS Total	62.80	1.08	65.14	0.93	0.261	63.79	1.15	63.65	0.8826	0.999	0.289
EIQ Ventursomeness	9.63	0.37	9.53	0.35	0.642	9.56	0.39	9.62	0.3316	0.945	0.664
EIQ Impulsivity	9.70	0.50	10.51	0.42	0.469	10.20	0.57	9.97	0.4013	0.741	0.347
SSS Disinhibition	5.40	0.27	5.86	0.25	0.583	5.81	0.32	5.52	0.2295	0.487	0.269
SSS Experience Seeking	5.44	0.21	5.36	0.20	0.360	5.71	0.25	5.25	0.1774	0.130	0.134
SSS Boredom Susceptibility	3.15	0.20	2.99	0.21	0.227	3.27	0.27	2.98	0.1754	0.314	0.193
SSS Thrill & Adventure Seeking	6.54	0.29	6.43	0.27	0.603	6.20	0.34	6.64	0.2495	0.346	0.514
SSS Total	20.63	0.66	20.51	0.63	0.323	20.77	0.74	20.48	0.5745	0.744	0.062
DDT*	0.06	.02–.21	0.04	.01–.15	0.006	0.08	.02–.19	0.04	.02–.14	0.183	0.006

*untransformed DDT value with median and IQR given instead of Mean and SE, p values from log transformed values
BIS = Barratt impulsivity Scale; EIQ = Eysenck Impulsivity Questionnaire; SSS = Sensation Seeking Scale; DDT = Delay Discounting Task.

ISSN: 1744-9081