Major Advance in Studying Fetal Development Using RNA Sequencing

Except for ultrasound, noninvasively monitoring the development of a human fetus is difficult. An international team studied the changing transcriptome — the circulating messenger RNA molecules that are produced by activated genes — in longitudinal studies of more than 1800 pregnant women of diverse ages, races and ethnicities, body-mass index, and other factors.

The team extracted and identified the sources of cell-free RNA (cfRNA; RNA from mother, placenta, and fetus that circulates in the mother's blood). Using machine learning, they identified combinations of cfRNAs that predicted gestational age and demonstrated the accuracy of this prediction (compared with ultrasound prediction) in independent groups of women. Then they measured the a…