Project Summary (2000-2005)

The objective of this project is to utilize recently developed knock out mouse models to investigate genetic susceptibility to environmentally-induced orofacial clefts (OFCs) and neural tube defects (NTDs). These two common human congenital defects are considered to be multifactorial traits, having both a significant genetic and an environmental component to their etiology. Researchers are directly testing the hypothesis that elevated levels of homocysteine cause OFCs and/or NTDs in the absence of folate depletion, especially when the embryo is exposed in utero to environmental toxicants. Additionally, the aryl hydrocarbon receptor (AhR) knockout mice, which are resistant to aromatic hydrocarbon (TCDD) toxicity, are being used to examine the genetic susceptibility to environmentally-induced birth defects using model environmental contaminants widely found in Texas' Rio Grande Valley as well as in the immediate environs of Sumqayit, Azerbaijan.