Fetal Alcohol Exposure Influences Brain Structure, Gene Function

The study focused on a gestational period when women don't often realize that they are pregnant.

Alcohol consumed early on in pregnancy may affect gene function in the brains of offspring, findings from a mouse model indicate.

The study, conducted by Nina Kaminen-Ahola, MD, and researchers at the University of Helsinki, also showed that differences in brain structure in offspring exposed to alcohol during gestation were apparent in adulthood.

The results may be significant since the study focused on a period of time that corresponds to the first three to four weeks of pregnancy after conception in humans — a period of time that many mothers are unaware of their pregnancy.

In the model, pregnant mice drank from a well of alcohol, inducing effects similar to fetal alcohol syndrome in their offspring. Genome-wide analysis of gene expression in the mouse hippocampus showed altered gene expression of 23 genes and three miRNAs in mice exposed to alcohol during gestation. The researchers also observed altered gene expression in bone marrow and the main olfactory epithelium, as well as altered DNA mythylation in the CpG islands upstream of the candidate genes in the hippocampus. MRI showed asymmetry of brain structures in ethanol-exposed adult offspring, including enlargement of the left hippocampus and decreased volume of the left olfactory bulb.

“The results support our assumption that alcohol permanently alters gene regulation at a very early stage,” said Kaminen-Ahola. “This would be significant for the challenging diagnostics of alcohol-induced damage. The mechanisms and biological markers which can aid in diagnosis are studied so that we can offer the developmental support necessitated by the damage as early as possible. Ideally, a swipe sample from inside the mouth of a newborn could reveal the extent of damage caused by early pregnancy alcohol exposure.”

Alcohol exposure during pregnancy in humans is associated with restricted growth, intellectual and learning disabilities, poor memory, coordination and speech and language delays, but it difficult to diagnose. The findings of the study could contribute to the use of biomarkers as a mode of diagnosing fetal alcohol syndrome. 


  1. Marjonen H et al. PLoS One. 2015; doi:10.1371/journal.pone.0124931.