Table 4.
Parameter estimates from models of natural log-transformed urine Hg levels (unadjusted and adjusted for specific gravity) with exposure predictor variables, genotype, and genotype-by-amalgam interactions. Models with polymorphisms that have significant genotype variable(s) in at least one urine model are reported. Beta coefficients (95% CI) are listed for each predictor variable. Statistically significant beta coefficients (p<0.05) are bolded.
| SNP | na | Adj. r2 | Amalgam | Amalgam Handledb | Non-Dentist | Genotype | Genotype* Amalgam |
|---|---|---|---|---|---|---|---|
| Base Model | 492 | 0.23 | 0.08 (0.06, 0.1) | 0.12 (0.04, 0.21) | -0.45 (-0.64, -0.25) | ||
| SEPP1 3’UTR | 240, 186, 35 | 0.25 | 0.03 (-0.03, 0.08) | 0.11 (0.03, 0.2) | -0.44 (-0.64, -0.24) | -0.26 (-0.43, -0.08) | 0.04 (0.01, 0.07) |
| GSTT1 deletion | 347, 71 | 0.24 | 0.08 (0.02, 0.15) | 0.12 (0.03, 0.21) | -0.4 (-0.6, - 0.19) | -0.18 (-0.48, 0.12) | 0 (-0.06, 0.05) |
|
| |||||||
| Sp. Gravity Adjusted Urine | |||||||
| Base Model | 491 | 0.22 | 0.07 (0.06, 0.09) | 0.09 (0.02, 0.16) | -0.28 (-0.44, -0.12) | ||
| SEPP1 3’UTR | 240, 186, 35 | 0.23 | 0.05 (0.01, 0.09) | 0.08 (0.01, 0.15) | -0.29 (-0.45, -0.12) | -0.09 (-0.24, 0.05) | 0.02 (-0.01, 0.04) |
| GSTT1 deletion | 347, 71 | 0.23 | 0.07 (0.02, 0.13) | 0.08 (0.01, 0.16) | -0.23 (-0.4, - 0.07) | -0.25 (-0.5, - 0.00) | 0 (-0.04, 0.05) |
a
Number of subjects in model in each genotype group. Gentoype groups are major homozygote, heterozygote, minor homozygote for SEPP1 3’UTR and gene present vs. double deletion for GSTT1.
b
Ordinal variable for number of amalgams removed and placed per week (see text for category cut-offs).