Mediating Effects of Maternal Blood Triglycerides on the Relationship between Prepregnancy Body Mass Index and Fetal Macrosomia.

OBJECTIVE: To examine whether the association of prepregnancy body mass index (BMI) with fetal macrosomia is mediated through maternal circulating lipid concentrations during pregnancy. STUDY DESIGN: In this prospective cohort, 3011 eligible pregnant women were enrolled. Information on demographic characteristics were collected using questionnaires, and anthropometrics and laboratory tests were performed at 24 weeks of gestation and before delivery. Macrosomia was defined as birth weight ≥4000 g. Logistic regression and multivariable linear regression, adjusted for age, fetal sex, education, gestational weight gain, fasting blood glucose, gestational diabetes, gestational hypertension, gestational age at delivery, delivery mode, and parity, were used to assess the mediation path between prepregnancy BMI, maternal serum lipids, and fetal macrosomia. RESULTS: A total of 2454 participants with completed records were included in the final analyses. Among the maternal circulating lipid biomarkers, only triglyceride was significantly associated with both prepregnancy BMI and fetal macrosomia risk, adjusting for potential confounders. Mediation analyses demonstrated that the direct effect of prepregnancy BMI on fetal macrosomia was 0.0085 (95% CI, 0.0003-0.018; P < .05), the indirect effect mediated through maternal serum triglycerides was 0.0016 (95% CI, 0.0007-0.0029; P < .001), and the estimated proportion of mediated effect was 15.7% (P < .05). CONCLUSIONS: Maternal circulating triglycerides mediate the association of prepregnancy BMI with the risk of fetal macrosomia.

CHRNA5 polymorphism and susceptibility to lung cancer in a Chinese population.

Polymorphisms in the nicotinic acetylcholine receptor subunit CHRNA5 gene have been associated with lung cancer positive susceptibility in European and American populations. In the present hospital-based, case-control study, we determined whether polymorphism in rs503464 of CHRNA5 is associated with lung cancer risk in Chinese individuals. A single nucleotide polymorphism in CHRNA5 rs503464, c.-166T>A (hereafter T>A), was identified using TaqMan-MGB probes with sequencing via PCR in 600 lung cancer cases and 600 healthy individuals. Genotype frequencies for rs503464 (T>A) were in Hardy-Weinberg equilibrium for the control population. However, genotype frequencies were significantly different between cases and controls (P < 0.05), while allele frequencies were not significantly different between groups. Compared to homozygous genotypes (TT or AA), the risk of lung cancer in those with the heterozygous genotype (TA) was significantly lower (OR = 0.611, 95%CI = 0.486-0.768, P = 0.001). Using genotype AA as a reference, the risk of lung cancer for those with genotype TA was increased 1.5 times (OR = 1.496, 95%CI = 1.120-1.997, P = 0.006). However, no difference in risk was observed between T allele carriers and A allele carriers (OR = 0.914, 95%CI = 0.779-1.073, P = 0.270). Stratification analysis showed that the protective effect of TA was more pronounced in those younger than 60 years, nonsmokers, or those without a family history of cancer, as well as in patients with adenocarcinoma or squamous cell carcinoma in clinical stages III or IV (P < 0.05). Therefore, the heterozygous genotype c.-166T>A at rs503464 of CHRNA5 may be associated with reduced risk of lung cancer, thus representing a susceptibility allele in Chinese individuals.

CHRNA5 polymorphism and susceptibility to lung cancer in a Chinese population

Polymorphisms in the nicotinic acetylcholine receptor subunit CHRNA5 gene have been associated with lung cancer positive susceptibility in European and American populations. In the present hospital-based, case-control study, we determined whether polymorphism in rs503464 of CHRNA5 is associated with lung cancer risk in Chinese individuals. A single nucleotide polymorphism in CHRNA5 rs503464, c.-166T>A (hereafter T>A), was identified using TaqMan-MGB probes with sequencing via PCR in 600 lung cancer cases and 600 healthy individuals. Genotype frequencies for rs503464 (T>A) were in Hardy-Weinberg equilibrium for the control population. However, genotype frequencies were significantly different between cases and controls (P < 0.05), while allele frequencies were not significantly different between groups. Compared to homozygous genotypes (TT or AA), the risk of lung cancer in those with the heterozygous genotype (TA) was significantly lower (OR = 0.611, 95%CI = 0.486-0.768, P = 0.001). Using genotype AA as a reference, the risk of lung cancer for those with genotype TA was increased 1.5 times (OR = 1.496, 95%CI = 1.120-1.997, P = 0.006). However, no difference in risk was observed between T allele carriers and A allele carriers (OR = 0.914, 95%CI = 0.779-1.073, P = 0.270). Stratification analysis showed that the protective effect of TA was more pronounced in those younger than 60 years, nonsmokers, or those without a family history of cancer, as well as in patients with adenocarcinoma or squamous cell carcinoma in clinical stages III or IV (P < 0.05). Therefore, the heterozygous genotype c.-166T>A at rs503464 of CHRNA5 may be associated with reduced risk of lung cancer, thus representing a susceptibility allele in Chinese individuals.