Analysis of fetal DNA from maternal peripheral blood by lectin‐polymerase chain reaction–single strand conformation polymorphism

Abstract

Fetal nucleated cells in maternal peripheral blood are a non-invasive source of fetal DNA for prenatal genetic diagnosis. However, the number of fetal cells present in maternal peripheral blood is very small. Therefore, fetal cell enrichment is generally considered necessary to allow detection and subsequent genetic analysis of the rare fetal cells. In the study presented here, we performed fetal cell separation from maternal blood using galactose-specific lectin to concentrate fetal nucleated red blood cells (FNRBCs), and attempted paternal diagnosis using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). Fetal cell separation was performed using galactose-specific lectin on a PV-MeA coated slide. Twenty cells consisting of an NRBC and its surrounding 19 maternal cells were collected using laser microdissection for stable DNA amplification. DNA analysis was performed using three sequence tagged site markers (D13S270, D17S5, and D18S474) by PCR-SSCP. All seven cases were informative because they showed heterozygosity at least one locus in D13S270, D17S5, or D18S474, and paternal-specific bands were detected in all cases. These results suggest that our proposed lectin-laser-micromanipulation-PCR-SSCP method may contribute to the development of prenatal diagnosis.

Practicability of prenatal testing using lectin‐based enrichment of fetal erythroblasts

“…The combination of the LCM technique with image analysis has the potential to become a leading method for analysis of fetal DNA, because selection of single cells by LCM can be used to provide the whole genome even if the sample only has a small number of erythroblasts. We previously amplified the SRY gene in erythroblasts isolated by MGG staining and manual detection combined with the LCM technique . In the present study, the X and Y chromosomes plus the SRY gene were found in erythroblasts identified by automated image analysis, which detected more cells than manual searching.…”