Influence of teratogenic factors on mouse 39 hox gene expression.

In normal development, each gene correctly expresses under temporal and spatial regulation. Teratogenic agents among environmental contaminants induce aberrated gene expression and consequently lead to congenital malformations. Therefore, it is urgent to identify molecular markers for the detection of teratogenic agents' effects.We analyzed mouse 39 hox gene expression in teratogenic factor exposed embryos. We found that 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) and retinoic acid (RA) affected differentially expression of hox. Unlike the RA-effects, TCDD led to broad repression of all hox loci. This different effect was also detected in miRNAs (microRNAs) expression in hox loci. Our results indicate that this irregular hox expression is a cause of congenital malformation, and suggest that monitoring of all hox expression works as a marker for environmental contaminants, including teratogenic effects.