The contamination levels of organochlorines and the pattern of gene expressions in human umbilical cords from intra-pairs of twins at delivery.

In this study, we examined the contamination levels of organochlorines and the patterns of gene expressions using umbilical cords of twins. The contamination levels of total PCBs, HCB and HCHs of intra-pair of twins were close to each other, but that of DDTs were not so as the others. It shows that the placental or fetal factor may influence the transfer or the accumulation of DDTs. The patterns of gene expressions of intra-pair of twins were similar to each other. It may because the environmental factor (sharing same mother), genetic factor or the both of twins are similar. This study gave us some information to understand the fetal exposure to organochlorines. Moreover, it showed the possibility that the pattern of gene expression in umbilical cord reflected the intra-uterine environment. However, the information from general pattern of the gene expression is limited. Therefore, further investigation is necessary to find new markers not only mRNA but also protein to estimate the effects of fetal exposure of multiple organochlorines.