Scientists unravel how alcohol harms developing foetus

SYDNEY - The fact that alcohol consumption during pregnancy can harm the developing foetus is long known. Research now explains the underlying mechanism behind the ill-effects of alcohol during pregnancy.

Even moderate consumption of alcohol during pregnancy affects the activity of genes in the developing foetus, lasting until adulthood, a new study says.

Suyinn Chong, of the Epigenetics Lab, Queensland Institute of Medical Research (QIMR), said: “We are looking at the mechanisms that control our genes - known as epigenetics… in other words whether they are switched on or off.”

“These epigenetic changes determine whether a gene is converted into protein, which ultimately controls physical traits,” said Chong.

“Using mice as a model, we have shown for the first time that alcohol consumed during the first trimester affects the developing foetus by altering the epigenetic information,” he added.

The researchers used specific mice, whose fur colour reflected these epigenetic changes. Half the mothers drank relatively moderate amounts of alcohol (equivalent to a peak blood alcohol reading of 0.12 in humans) during pregnancy, while the other half consumed water.

The mice that drank alcohol had twice as many dark-furred offspring compared to mothers who were not exposed to alcohol. The resulting change in coat colour is an indication of the changed epigenetic state of the coat colour gene, said a QIMR release.

Some alcohol-exposed offspring exhibited subtle skull malformations, similar to features seen in human fetal alcohol syndrome (FAS) - a condition that causes growth restriction, intellectual disabilities and changes to the shape and size of the skull as a result of high levels of alcohol consumption during pregnancy.

The paper was published in PLoS Genetics.