Women who are exposed to trauma, illness or alcohol during pregnancy are more likely to have a child with neurological or psychiatric disorder, according to a recent study.

Researchers found that stressors may activate a single molecular trigger in brain cells that can go awry and activate conditions such as schizophrenia, post-traumatic stress disorder and some forms of autism. The new study identifies a molecular mechanism in the prenatal brain that may help explain how cells go awry when exposed to certain environmental conditions.

"Past studies have shown that when an expectant mother exposes herself to alcohol or drug abuse or she experiences some trauma or illness, her baby may later develop a psychiatric disorder, including some forms of autism or post-traumatic stress disorder, later in life," researchers said in the study.

For the study, researchers created stem cells from biopsies of people diagnosed with schizophrenia. Stem cells are capable of becoming many different tissue types, including neurons.

Researchers found that mouse embryos exposed to alcohol, methyl-mercury, or maternal seizures activate a single gene, HSF1, also known as heat shock factor, in cerebral cortex. In the study, genes from the stem cells of those with schizophrenia responded more dramatically when exposed to environmental insults than stem cells from non-schizophrenic individuals.

The gene, HSF1, plays a crucial role in of brain cells to prenatal environmental insults.

"The gene protects and enables brain cells to survive prenatal assaults. Mice lacking the HSF1 gene showed structural brain abnormalities and were prone to seizures after birth following exposures to very low levels of toxins," researchers said.

Kazue Hasimoto-Torii, lead author of the study, noted that autism rates have increased substantially and more people are having these exposures to environmental stressor. While there have been many studies that have identified singular stressors, such as alcohol, there have not been enough studies to focus on many different environmental factors and their impacts, such as heavy metals as well as alcohol and other toxic exposure, she adds.