TABLE 5.
TRANSFORMING GROWTH FACTOR-β1 C-509T GENOTYPES AND rs4803457T/−509T DIPLOTYPES AND EXPOSURE TO MATERNAL SMOKING IN UTERO AND EARLY PERSISTENT ASTHMA
| In Utero Maternal Smoking | No Asthma (n) | Early Persistent Asthma
|
||||
|---|---|---|---|---|---|---|
| n | OR (95% CI) | |||||
| rs1800469 (C-509T) | ||||||
| CC/CT | No | 1,844 | 107 | 1.0 (Ref.) | ||
| TT | No | 281 | 22 | 1.47 (0.87–2.48) | ||
| CC/CT | Yes | 382 | 29 | 0.99 (0.59–1.66) | ||
| TT | Yes | 52 | 9 | 3.41 (1.46–7.80) | ||
| P = 0.11* | ||||||
| No. of rs4803457T/−509T diplotypes | ||||||
| 0 or 1 | No | 1.0 (Ref.) | ||||
| 2 | No | 1.49 (0.88–2.52) | ||||
| 0 or 1 | Yes | 0.99 (0.59–1.66) | ||||
| 2 | Yes | 3.43 (1.46–8.03) | ||||
| P = 0.12* | ||||||
Definition of abbreviations: CI = confidence interval; OR = odds ratio.
ORs adjusted for child's age, sex, ethnicity, atopy, health insurance status, and community of residence, and parental education, parental asthma, annual family income, residential distance from nearest freeway, and number of smokers at home.
*
The P value for the in utero maternal smoking by TGF-β1–C-509T interaction was obtained from likelihood ratio tests from a nonstratified model with appropriate interaction terms and was based on 1 degree of freedom.