Research Article

Genotype-Based Bayesian Analysis of Gene-Environment Interactions with Multiple Genetic Markers and Misclassification in Environmental Factors

Table 1

Biases and root mean squared errors (RMSEs) of risk parameters for the naive approach that ignores existence of misclassification and the proposed method in the case when pr ( 𝐷 = 1 ) is known and when it is estimated. The results are based on 500 samples of 1,500 cases and 1,500 controls. Genotype is simulated at the three marker loci with 𝑃 𝑀 𝑖 = 0 . 2 5 , 𝑖 = 1 , 2 , 3 , with linkage disequilibrium corresponding to Δ 𝑀 𝑖 𝑀 𝑗 = 0 . 0 3 . The environmental covariate ( 𝑋 ) is binary and measured with error with misclassification probabilities being 0 . 2 0 for exposed and 0 . 2 5 for nonexposed subjects. The data is simulated and analyzed under the genotype effect model.

ParameterTrue valueNaive analysisPseudo-MLEMCMC
BiasRMSEBiasRMSEBiasRMSE

κ0.4840.4810.231−0.0540.020−0.0320.013
β X0.693−0.3510.1320.0140.0390.0080.021
β A10.4060.2570.073−0.0110.016−0.0030.009
β A20.7890.1940.046−0.0030.015−0.0020.006
β A30.6930.2830.089−0.0050.016−0.0030.008
β AX10.916−0.4250.1930.0390.0460.0170.025
β AX20.693−0.3170.1130.0380.0410.0230.021
β AX31.099−0.5150.2820.0390.0580.0190.032
β D10.2620.2990.1330.0260.1520.0090.368
β D20.0950.2580.1050.0050.0990.0030.039
β D30.6930.2310.0920.0180.1280.0080.087
β DX11.099−0.4950.3260.0180.3010.0060.093
β DX20.916−0.4130.2350.0060.2080.0050.121
β DX31.099−0.4860.3130.0230.2860.0170.138
𝑃 𝑀 𝑖 0.250<0.001<0.001−0.001<0.001<0.001<0.001
pr ( 𝑋 = 1 ) 0.500    0.0030.001<0.001<0.001
pr ( 𝐷 = 1 ) 0.005    0.003<0.001<0.001<0.001