Facial Abnormalities of Fetal Alcohol Syndrome (FAS)

Prenatal exposure to alcohol (ethanol) results in a continuum of physical, neurological, behavioral, and learning defects collectively grouped under the heading Fetal Alcohol Spectrum Disorder (FASD). Fetal Alcohol Syndrome [4] (FAS) was first defined in 1973 as a condition characterized by preand postnatal growth deficiencies, facial abnormalities, and defects of the central nervous system [5]. The pattern of facial defects that occur as a result of ethanol exposure during development primarily affects the midline of the face, altering morphology [6] of the eyes, nose, and lips. Ethanol damage to cranial neural crest cells [7] (CNCC) early in embryonic development is responsible for these minor midline abnormalities. Regulation of the gene sonic hedgehog [8] (shh) during this period of development has been observed to rescue [9] these ethanol-affected CNCC from fated cell death, an association that has not yet been examined as it applies to human cells.