Vitamin B-12 Status during Pregnancy and Child's IQ at Age 8: A Mendelian Randomization Study in the Avon Longitudinal Study of Parents and Children

Carolina Bonilla*, Debbie A. Lawlor, Amy E. Taylor, David J. Gunnell, Yoav Ben-Shlomo, Andy R Ness, Nicholas J. Timpson, Beate St Pourcain, Susan M. Ring, Pauline M. Emmett, A. David Smith, Helga Refsum, Craig E. Pennell, Marie-Jo Brion, George Davey Smith, Sarah J. Lewis

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

18 Citations (Scopus)

Abstract

Vitamin B-12 is essential for the development and maintenance of a healthy nervous system. Brain development occurs primarily in utero and early infancy, but the role of maternal vitamin B-12 status during pregnancy on offspring cognitive function is unclear. In this study we assessed the effect of vitamin B-12 status in well-nourished pregnant women on the cognitive ability of their offspring in a UK birth cohort (ALSPAC). We then examined the association of SNPs in maternal genes FUT2 (rs492602) and TCN2 (rs1801198, rs9606756) that are related to plasma vitamin B-12, with offspring IQ. Observationally, there was a positive association between maternal vitamin B-12 intake and child's IQ that was markedly attenuated after adjustment for potential confounders (mean difference in offspring IQ score per doubling of maternal B-12 intake, before adjustment: 2.0 (95% CI 1.3, 2.8); after adjustment: 0.7 (95% CI -0.04, 1.4)). Maternal FUT2 was weakly associated with offspring IQ: mean difference in IQ per allele was 0.9 (95% CI 0.1, 1.6). The expected effect of maternal vitamin B-12 on offspring IQ, given the relationships between SNPs and vitamin B-12, and SNPs and IQ was consistent with the observational result. Our findings suggest that maternal vitamin B-12 may not have an important effect on offspring cognitive ability. However, further examination of this issue is warranted.
Original languageEnglish
Article numberARTN e51084
Pages (from-to)e51084
Number of pages9
JournalPLoS ONE
Volume7
Issue number12
DOIs
Publication statusPublished - 5 Dec 2012

Structured keywords

  • Brain and Behaviour
  • Tobacco and Alcohol

Keywords

  • TRANSCOBALAMIN GENE
  • GENOME-WIDE ASSOCIATION
  • COGNITIVE FUNCTION
  • HOMOCYSTEINE
  • GENETIC EPIDEMIOLOGY
  • PLASMA
  • FOLATE
  • POLYMORPHISM
  • COBALAMIN STATUS
  • POPULATION

Fingerprint Dive into the research topics of 'Vitamin B-12 Status during Pregnancy and Child's IQ at Age 8: A Mendelian Randomization Study in the Avon Longitudinal Study of Parents and Children'. Together they form a unique fingerprint.

Cite this