Table 1.

Calculation of an Optimal ROC Curve: Three SNPs

Allele Freq.a (Case;Control)			Genotype Freq.b (Case;Population)			Multilocus Genotype Freq.c (Case;Control)	Likelihood Ratiod	Rank Ordere
rs5219	rs1801282	rs7903146	rs5219	rs1801282	rs7903146	rs5219x rs1801282x rs7903146
0.384;0.354	0.099;0.123	0.384;0.3	0.147;0.126	0.010;0.015	0.147;0.093	0.0002;0.0002	1.236	7
					0.473;0.423	0.0007;0.0006	1.086	11
					0.379;0.484	0.0005;0.0006	0.954	15
				0.178;0.214	0.147;0.093	0.0039;0.0024	1.590	3
					0.473;0.423	0.0124;0.0089	1.394	6
					0.379;0.484	0.0100;0.0082	1.223	9
				0.812;0.771	0.147;0.093	0.0177;0.0086	2.052	1
					0.473;0.423	0.0566;0.0316	1.794	2
					0.379;0.484	0.0454;0.0289	1.570	4
			0.473;0.458	0.010;0.015	0.147;0.093	0.0007;0.0008	0.855	16
					0.473;0.423	0.0022;0.0029	0.753	19
					0.379;0.484	0.0018;0.0027	0.663	23
				0.178;0.214	0.147;0.093	0.0124;0.0114	1.094	10
					0.473;0.423	0.0399;0.0415	0.962	13
					0.379;0.484	0.0320;0.0378	0.846	17
				0.812;0.771	0.147;0.093	0.0566;0.0404	1.402	5
					0.473;0.423	0.1817;0.1476	1.231	8
					0.379;0.484	0.1457;0.1349	1.080	12
			0.379;0.415	0.010;0.015	0.147;0.093	0.0005;0.0009	0.590	24
					0.473;0.423	0.0018;0.0034	0.521	26
					0.379;0.484	0.0014;0.0031	0.459	27
				0.178;0.214	0.147;0.093	0.0100;0.0133	0.753	20
					0.473;0.423	0.0320;0.0483	0.663	22
					0.379;0.484	0.0257;0.0440	0.584	25
				0.812;0.771	0.147;0.093	0.0454;0.0473	0.960	14
					0.473;0.423	0.1457;0.1725	0.845	18
					0.379;0.484	0.1169;0.1572	0.743	21

Details of using the optimal ROC-curve approach for the three SNPs used by Weedon et al.³

^aAllele-frequency estimates obtained from Weedon et al.³

^bGenotype frequencies are computed assuming Hardy-Weinberg equilibrium separately for the case and the control populations.

^cMultilocus genotype probabilities given disease status calculated with Equation 3.

^dLikelihood ratios calculated with Equation 4.

^eRank order of the LRs.