TABLE IV.
Adjusted Associations* Between Maternal Smoking from the Month Before Through the Third Month of Pregnancy and Selected Xenobiotic Metabolizing Enzyme Gene Variants and Gastroschisis for Non-Hispanic White and Hispanic Mothers and Infants Using Data from the National Birth Defects Prevention Study, 1997-2003.
| Variant Alleles** |
Maternal Smoking |
Control | Case | aOR (95% CI) | P | Control | Case | aOR (95% CI) | P |
|---|---|---|---|---|---|---|---|---|---|
| Infants | Mothers | ||||||||
| Non-Hispanic White | |||||||||
| CYP1A1*2A | |||||||||
| Absent | None | 598 | 25 | Referent | 681 | 37 | Referent | ||
| Present | None | 166 | 13 | 1.56 (0.73-3.36) | 0.25 | 192 | 13 | 1.00 (0.48-2.05) | 1.00 |
| Absent | Any | 136 | 33 | Referent | 181 | 49 | Referent | ||
| Present | Any | 37 | 8 | 0.89 (0.36-2.17) | 0.79 | 46 | 6 | 0.38 (0.15-0.98) | 0.05 |
| CYP1A2*1C | |||||||||
| Absent | None | 744 | 33 | Referent | 841 | 47 | Referent | ||
| Present | None | 20 | 5 | 3.19 (0.93-10.98) | 0.07 | 32 | 3 | n/c | |
| Absent | Any | 162 | 39 | Referent | 221 | 54 | Referent | ||
| Present | Any | 9 | 2 | n/c | 5 | 1 | n/c | ||
| CYP1A2*1F | |||||||||
| Absent | None | 385 | 15 | Referent | 452 | 21 | Referent | ||
| Present | None | 379 | 23 | 1.80 (0.87-3.72) | 0.11 | 421 | 29 | 1.69 (0.90-3.19) | 0.10 |
| Absent | Any | 80 | 23 | Referent | 93 | 25 | Referent | ||
| Present | Any | 92 | 18 | 0.74 (0.36-1.52) | 0.42 | 133 | 30 | 1.04 (0.56-1.95) | 0.89 |
| NAT2*5 | |||||||||
| Absent | None | 226 | 12 | Referent | 265 | 11 | Referent | ||
| Present | None | 538 | 26 | 1.20 (0.56-2.58) | 0.64 | 608 | 39 | 1.57 (0.75-3.30) | 0.23 |
| Absent | Any | 46 | 12 | Referent | 67 | 16 | Referent | ||
| Present | Any | 127 | 29 | 1.09 (0.50-2.40) | 0.83 | 160 | 37 | 0.95 (0.48-1.88) | 0.89 |
| NAT2*6 | |||||||||
| Absent | None | 381 | 14 | Referent | 437 | 20 | Referent | ||
| Present | None | 383 | 24 | 1.52 (0.73-3.14) | 0.26 | 435 | 30 | 1.55 (0.82-2.92) | 0.17 |
| Absent | Any | 78 | 23 | Referent | 104 | 24 | Referent | ||
| Present | Any | 95 | 18 | 0.69 (0.34-1.41) | 0.30 | 123 | 31 | 1.17 (0.63-2.16) | 0.63 |
| Hispanic | |||||||||
| CYP1A1*2A | |||||||||
| Absent | None | 85 | 13 | Referent | 108 | 17 | Referent | ||
| Present | None | 153 | 22 | 0.97 (0.45-2.10) | 0.94 | 168 | 30 | 1.09 (0.56-2.13) | 0.80 |
| Absent | Any | 10 | 1 | Referent | 9 | 3 | Referent | ||
| Present | Any | 16 | 4 | n/c | 19 | 8 | n/c | ||
| CYP1A2*1C | |||||||||
| Absent | None | 117 | 14 | Referent | 133 | 18 | Referent | ||
| Present | None | 122 | 21 | 1.51 (0.71-3.20) | 0.28 | 144 | 29 | 1.48 (0.76-2.85) | 0.25 |
| Absent | Any | 15 | 2 | Referent | 14 | 4 | Referent | ||
| Present | Any | 11 | 3 | n/c | 14 | 7 | 1.75 (0.42-7.40) | 0.44 | |
| CYP1A2*1F | |||||||||
| Absent | None | 114 | 12 | Referent | 147 | 20 | Referent | ||
| Present | None | 125 | 23 | 2.10 (0.96-4.59) | 0.06 | 130 | 27 | 1.61 (0.84-3.09) | 0.15 |
| Absent | Any | 11 | 2 | Referent | 10 | 5 | Referent | ||
| Present | Any | 15 | 3 | n/c | 18 | 6 | 0.65 (0.15-2.84) | 0.57 | |
| NAT2*5 | |||||||||
| Absent | None | 113 | 16 | Referent | 130 | 20 | Referent | ||
| Present | None | 126 | 19 | 1.07 (0.51-2.24) | 0.86 | 147 | 27 | 1.36 (0.70-2.61) | 0.36 |
| Absent | Any | 13 | 1 | Referent | 12 | 3 | Referent | ||
| Present | Any | 13 | 4 | n/c | 16 | 8 | n/c | ||
| NAT2*6 | |||||||||
| Absent | None | 157 | 18 | Referent | 189 | 25 | Referent | ||
| Present | None | 82 | 17 | 2.11 (1.00-4.48) | 0.05 | 88 | 22 | 2.17 (1.12-4.19) | 0.02 |
| Absent | Any | 15 | 3 | Referent | 18 | 7 | Referent | ||
| Present | Any | 11 | 2 | n/c | 10 | 4 | 1.03 (0.24-4.40) | 0.97 | |
*
Adjusted for maternal age at delivery (continuous)
**
Dominant mode of inheritance used for CYP1A1*2A, CYP1A2*1C, NAT2*5, and NAT2*6; Recessive mode of inheritance used for CYP1A2*1F
n/c= not calculated because of low numbers (< 4)