Abstract: This application provides methods and systems for paternity determination. In some embodiments, the method is a non-invasive prenatal paternity determination method, which comprises obtaining genotypes for one or more polymorphic nucleic acid targets in a genomic DNA sample obtained from an alleged father, isolating cell-free nucleic acids from a biological sample obtained from the pregnant mother comprising fetal nucleic acids. The amount of each allele of one or more polymorphic nucleic acid targets in cell-free nucleic acids are determined and informative polymorphic nucleic acid targets are identified. Next, the allele frequency of each allele of the selected informative polymorphic nucleic acid targets is measured and fetal genotypes for each selected informative polymorphic nucleic acid targets are determined based on the allele frequency. Finally, the paternity status of the fetus are determined based on the genotypes of the mother, alleged father and the fetus for the informative nucleic acid targets.

Abstract: This application provides methods and systems for determining transplant status. In some embodiments, the method comprises obtaining a biological sample from hematopoietic stem cell transplant (HSCT) recipient; measuring the amount of one or more identified recipient-specific nucleic acids or donor-specific nucleic acids in the sample; and (c) determining transplant status by monitoring the amount of the one or more identified recipient-specific nucleic acids or donor-specific nucleic acids after transplantation. In some approaches, the one or more recipient-specific or the donor-specific nucleic acids are identified based on the amount of one or more polymorphic nucleic acid targets, which can be used to determine the transplant status. Optionally, the biological sample is blood or bone marrow. Optionally the nucleic acid is genomic DNA.

Abstract: This application provides methods and systems for determining transplant status. In some embodiments, the method comprises obtaining a biological sample from an organ transplant recipient who has received an organ; isolating cell-free nucleic acids from the biological sample; measuring the amount of each allele of one or more polymorphic nucleic acid targets in the biological sample; identifying the donor specific allele using a computer algorithm based on the measurements of the one or more polymorphic nucleic acid targets, whereby detecting one or more donor-specific circulating cell-free nucleic acids, detecting tissue injury based on the presence or amount of said one or more donor-specific nucleic acids, thereby determining transplant status.