Analysis of nucleic acids associated with extracellular vesicles in pregnant females

Abstract

Cell-free nucleic acid from extracellular particles (EPs) is analyzed. A sample can be purified for the extracellular particles. As examples, the purification can include centrifuging, washing, and a nuclease treatment. To increase the fetal fraction, the purification can enrich a sample for a certain type of EPs (e.g., long EPs). In this manner, a desired population of particles can be selected for the analysis of their nucleic acids. As part of an analysis of the nucleic acid molecules (fragments) from an enriched sample, nucleic acid molecules greater than a certain size can be selected, which can increase genetic and/or epigenetic informativeness, without an adverse effect (e.g., the reduction of fetal DNA fraction). The long nucleic acid fragments can be analyzed in various ways, including using short read sequencing techniques that perform fragmentation before sequencing and using long read sequencing techniques.