Background: Fetal alcohol spectrum disorder (FASD) is used to describe the spectrum of birth defects due to prenatal alcohol exposure; these include craniofacial abnormalities and intellectual disabilities. The prevalence of FASD is estimated at 1 in 100. Diagnostic criteria include distinct facial features, neurodevelopmental deficits and confirmation of alcohol use during pregnancy. Unfortunately, often criteria are missed or absent. No biochemical marker is available for screening and diagnosis of FASD that is easy, accurate and cost-effective. Methods: Five children are being recruited from both the FASD clinic at the Glenrose Rehabilitation Hospital and the Healthy Infants and Children’s Clinical Research Program (HICUPP) registry. The levels of exhaled nasal NO will be measured and compared between the two groups. Metabolomics analysis on urine samples targeting metabolites of the NO pathway, along with other urinary metabolites is being performed. Bioinformatic statistical tools will be applied to determine whether measured metabolite profiles can provide distinct signatures between healthy children and children with FASD. Results: This project is ongoing. Conclusions: We hope to correlate NO levels with FASD, illustrating the relationship between NO, ciliopathies and development of FASD. As well, we hope to determine whether urinary metabolites may yield diagnostic markers of FASD.