ABSTRACT
OBJECTIVE: We used nucleated erythrocytes in maternal blood for prenatal determination of the fetal gender as the preliminary experiment for the screening of fetal genetic status and the BclI DNA polymorphism in an attempt to clarify the origin of erythrocytes in maternal blood. METHODS: In seventeen pregnant women, venous blood was withdrawn and the nucleated erythrocytes were recovered by magnetic activated cell sorting (MACS) and immunostaining. After isolation of nucleated erythrocytes by micromanipulation, we performed nested PCR for amelogenin gene to identify the fetal gender and performed BclI DNA polymorphism to clarify the origin of erythrocytes. RESULTS: We could amplify the minute DNA in a single cell by primer extension preamplification and nested PCR of amelogenin gene in 94 (48.7%) cells and could identify the fetal gender by 58.8%. BclI DNA polymorphism revealed that the several cells, which did not reveal the specific band of Y chromosome in spite of the pregnancy of male fetuses, must be the cells from mother. CONCLUSION: Through this study, we could conclude that several nucleated erythrocytes in maternal blood circulation can originate from mother, therefore we must develop the new method to identify the nucleated erythrocyte of fetal origin. Considering that we must apply for the larger number of pregnant women to screen, the procedure was multi-step and complex. Therefore, we must design the new scheme to utilize the nucleated erythrocytes in maternal blood.