Fetal nucleic acids in maternal body fluids: an update

Area of Science:

• Reproductive biology
• Genetics
• Biomarker development

Background:

• Cell-free fetal DNA (cfDNA) and mRNA in maternal circulation and amniotic fluid are promising biomarkers for prenatal diagnosis.
• Understanding factors influencing cfDNA levels and fetal gene expression is crucial for clinical applications.

Purpose of the Study:

• To investigate factors affecting cell-free fetal DNA (cfDNA) levels in maternal blood.
• To explore the relationship between placental volume and cfDNA levels.
• To analyze fetal gene expression and molecular karyotype using cfDNA and mRNA from maternal samples and amniotic fluid.

Main Methods:

• Analysis of cfDNA and mRNA levels in maternal plasma, serum, and amniotic fluid.
• Development of a mouse model for cfDNA detection.
• Three-dimensional ultrasound for placental volume assessment.
• DNA microarray hybridization for molecular karyotyping.

Main Results:

• Maternal weight significantly affects cfDNA levels, while race, parity, and conception type do not.
• No association was found between placental volume and cfDNA levels.
• Optimized recovery methods revealed differences in fetal DNA between blood and amniotic fluid.
• Preliminary data on fetal gene expression in amniotic fluid and cfDNA-based molecular karyotyping were obtained.

Conclusions:

• Cell-free fetal nucleic acids are valuable for noninvasive prenatal testing, including fetal Rhesus D assessment.
• Maternal weight is a key factor in interpreting cfDNA levels.
• Further research into fetal gene expression and molecular karyotyping using cfDNA and mRNA holds significant potential for prenatal diagnosis.