Candidate gene study for smoking, alcohol use, and body weight in a sample of pregnant women

Abstract

Objective: Prenatal smoking, alcohol use, and obesity have significant effects on maternal and fetal health. However, not much is known about the genetic contributions to these risk factors among pregnant women. We evaluate the associations between several candidate genes and smoking, alcohol use, pre-pregnancy body weight, and weight gain during pregnancy in a sample of pregnant women.

Methods: The study analyzes a sample of about 1900 mothers from the Danish National Birth Cohort. We test the association between 1450 SNPs in/near 117 genes/loci and various risk factor measures.

Results: Only a few SNPs in FTO were significantly associated with pre-pregnancy obesity and body mass index (4 and 2 SNPs, respectively) after SNP-level correction for multiple testing. A few loci were significantly related to various smoking measures (any smoking, quitting and cigarette number) with gene/locus-level correction for multiple testing, but not after SNP-level correction. Similarly, some loci were significant for the alcohol measures at the gene/locus-level but not at SNP-level correction.

Conclusion: The study suggests that the majority of the evaluated candidate genes may not play an important role in influencing these risk factors among pregnant women, highlighting the importance of other genetic factors and non-genetic contributors to their etiology.

• Child health
• fetal health
• maternal health
• prenatal risks
• pre-pregnancy weight

Acknowledgements

The authors thank Drs. Mads Melbye, Bjarke Feenstra, and Heather Boyd for providing data on variables used in the analysis.

Declaration of interest

The authors have no financial disclosures or conflicts of interest with this work. The Prematurity GWAS from which data were used was funded by NIH grant U01 HG-4423. The data analyses for this paper were funded by NIH/NIDCR grant R01 DE020895.

Supplementary materials available online:

Supplementary Table A1