Prenatal alcohol exposure is the leading preventable cause of birth defects in the United States, producing an array of neurological, behavioral and physical abnormalities collectively known as fetal alcohol spectrum disorders (FASD). Early intervention and treatment programs have been shown to reduce some of the long-term adverse effects, but this is dependent on identifying children at risk of fetal damage which is not detected in most cases. Many children affected by FASD do not exhibit obvious physical indications of prenatal alcohol-associated birth defects, creating challenges in making timely and accurate diagnoses. There is a critical need for development of biomarkers that can detect babies heavily exposed to alcohol throughout pregnancy to predict those at risk for developing the neurobehavioral and developmental disabilities associated with FASD. Prenatal alcohol exposure has been shown to alter DNA methylation patterns of genes known to play important roles in development and contribute to abnormal embryonic development, suggesting that alcohol-associated alterations in DNA methylation profiles, identified from neonatal blood spot samples, could be used as an alcohol biomarker in neonates. Findings from our Phase I study demonstrate that epigenetic profiles, specifically the differences in site-specific CpG DNA methylation, can differentiate the incidence of prenatal alcohol exposure using neonatal blood spots. The proposed SBIR Phase II project seeks to develop and validate the technology to generate quantitative DNA methylation screening assays using bisulfite pyrosequencing to analyze the differentially methylated sites that were found to be significantly associated with prenatal alcohol exposure. The technology that we will develop will use samples that are already routinely collected from newborns for comprehensive genetic screening assays (heel stick blood spots) and more recently for prenatal alcohol exposure screening (umbilical cord and heel stick blood spots) to 1) extract and purify genomic DNA using an automated system; 2) perform bisulfite-PCR reactions; and 3) screen for epigenetic DNA methylation biomarkers of prenatal alcohol exposure using pyrosequencing. These assays will be used to screen genomic DNA collected from a large sampling of PEth positive and PEth negative neonatal blood spots to identify the epigenetic modifications that most significantly correlate with fetal alcohol exposure. Our long-term goal is to examine whether there is a correlation between these epigenetic biomarkers and an increased risk for the developmental disabilities associated with FASD.
The prevalence of FASD is now estimated to be as high as 2 to 5% of school children, making prenatal alcohol exposure the most preventable source of birth defects in the United States. Early intervention and treatment programs have been shown to reduce some of the long-term adverse effects, but this is dependent on identifying children at risk of fetal alcohol damage which is not possible in most cases. The proposed Phase II project will develop and validate the technology to run quantitative DNA methylation screening assays using bisulfite pyrosequencing from newborn dried blood spot samples to analyze differentially methylated sites that were shown to be significantly associated with prenatal alcohol exposure in the Phase I study with the goal of validating an epigenetic biomarker of prenatal alcohol exposure.
