Genotype and Womb Environment Epigenetically Influence Babies’ Development

A multitude of studies support that the quality of a child’s environment in the womb significantly influences health and development over his or her lifetime. Scientists at the University of Southampton, UK and National University of Singapore have analyzed epigenetic marks on DNA in order to determine how much a baby’s development in the womb is dictated by his or her genotype compared to the mother’s mental and physical health.

In the study published in Genome Research, scientists used samples of umbilical cord tissue DNA from 237 individuals (131 Chinese, 72 Malay, 34 Indian) in the Singapore GUSTO Birth Cohort Study. The researchers analyzed the genotype and DNA methylomes using Illumina’s Infinium array technology, finding that 1,432 punctuate regions of the methylome were highly variable – also known as variably methylated regions (VMRs) – when compared against a “backdrop of homogeneity.”

Researchers used extensive statistical models to analyze the effect of genetic polymorphism alone, prenatal environment alone, and the interaction of genetic differences and prenatal environment. They found that 25% of the epigenetic variation between babies was best explained by genetic differences alone and 75% was best explained by the interaction of genetic differences and the prenatal environment. Environmental factors included birth weight, gestational age, maternal smoking, and maternal depression, all of which are known to influence numerous developmental outcomes.

The results show that most of the variation between babies is not due to fixed genetic changes, but, rather, due to interactions between the babies’ environment in the womb and genetic information passed down from the parents. The study emphasizes the importance of the genotype, which seems to be an essential factor in the relationship between DNA methylation and phenotype. According to the researchers, this study marks “to [their] knowledge, the first attempt to quantify the relative influence of genotype and environment, and their interaction on the human epigenome.”

Source: Learn all about it and read more about their findings here: The effect of genotype and in utero environment on inter-individual variation in neonate DNA methylomes. Teh, AL., et al.

Reference: University of Southampton, International study gives new insights into development in the womb. University of Southampton. April 28, 2014.