Although little is known about the causes of autism spectrum disorders (ASD), scientists now believe that the interaction of genetics and environmental exposures are the key to unlocking the mystery. Prenatal exposure to certain drugs (for example, the notorious birth-defect causing drug thalidomide) have been linked to autism risk. While these drugs are no longer prescribed to during pregnancy, for women with certain chronic medical conditions such as epilepsy, diabetes, inflammatory bowel disease and asthma, the use of medication is essential during pregnancy. Nicole Gidaya, a PhD student, is pursuing research to determine if some medications used by pregnant women today could be linked to autism risk.
Such research is needed since the teratogenicity of most drugs – their risk of causing birth defects – is still undetermined, especially with respect to neurodevelopmental outcomes. For women requiring prescription medication to control their chronic medical conditions, medical belief typically holds that the benefits for mother and child will outweigh risks from exposure to the medication. Gidaya plans to investigate two specific classes of drugs which are commonly used during pregnancy and pose a risk for ASD. Beta-2 adrenergic receptor agonists (B2AR) are used to reduce asthma attacks and to provide asthma control in adults. Selective serotonin reuptake inhibitors (SSRIs) are among the most prescribed medication used to treat depression.
To investigate the association of these drugs and risk for ASD, the first component of her project involves evaluating data from Denmark, which has a state run health system. Danish health registries will provide detailed information regarding prescription drugs used during pregnancy and autism diagnosis, as well as health and socioeconomic status by linking individuals’ unique civil-registry number. The second component of her research involves determining if effects of prenatal exposure to medications might be greater in children with genetically determined differences in the ability to metabolism of the drugs.
When completed, this research will add to the sparse body of literature on genotypes that could affect risks for autism by altering susceptibility to an environmental exposure.