Dynamic interaction between fetal adversity and a genetic score reflecting dopamine function on developmental outcomes at 36 months

PLoS One. 2017 May 15;12(5):e0177344. doi: 10.1371/journal.pone.0177344. eCollection 2017.

Abstract

Background: Fetal adversity, evidenced by poor fetal growth for instance, is associated with increased risk for several diseases later in life. Classical cut-offs to characterize small (SGA) and large for gestational age (LGA) newborns are used to define long term vulnerability. We aimed at exploring the possible dynamism of different birth weight cut-offs in defining vulnerability in developmental outcomes (through the Bayley Scales of Infant and Toddler Development), using the example of a gene vs. fetal adversity interaction considering gene choices based on functional relevance to the studied outcome.

Methods: 36-month-old children from an established prospective birth cohort (Maternal Adversity, Vulnerability, and Neurodevelopment) were classified according to birth weight ratio (BWR) (SGA ≤0.85, LGA >1.15, exploring a wide range of other cut-offs) and genotyped for polymorphisms associated with dopamine signaling (TaqIA-A1 allele, DRD2-141C Ins/Ins, DRD4 7-repeat, DAT1-10- repeat, Met/Met-COMT), composing a score based on the described function, in which hypofunctional variants received lower scores.

Results: There were 251 children (123 girls and 128 boys). Using the classic cut-offs (0.85 and 1.15), there were no statistically significant interactions between the neonatal groups and the dopamine genetic score. However, when changing the cut-offs, it is possible to see ranges of BWR that could be associated with vulnerability to poorer development according to the variation in the dopamine function.

Conclusion: The classic birth weight cut-offs to define SGA and LGA newborns should be seen with caution, as depending on the outcome in question, the protocols for long-term follow up could be either too inclusive-therefore most costly, or unable to screen true vulnerabilities-and therefore ineffective to establish early interventions and primary prevention.

MeSH terms

  • Child Development*
  • Child, Preschool
  • Disease Susceptibility*
  • Dopamine / physiology*
  • Female
  • Fetal Development / genetics*
  • Fetal Growth Retardation*
  • Genetic Linkage
  • Genetic Predisposition to Disease*
  • Genotype
  • Humans
  • Linkage Disequilibrium
  • Male
  • Quantitative Trait Loci
  • Risk Factors

Substances

  • Dopamine

Grant support

This work was funded by the Canadian Institutes of Health Research (CIHR), the JPB Foundation and the Sackler Institute. These sponsors had no influence on the study design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. Bischoff AR wrote the first draft of the manuscript, and although we had financial support from these granting agencies for the project no honorarium, grant, or other form of payment was given to anyone to produce specifically this manuscript.