Patent ID: 11970742
Assignee: THE CHINESE UNIVERSITY OF HONG KONG
Field: Computer technology (Electrical engineering)
Classification: CPC C  G | IPC C  G

Claim 8:
9. The method of claim 1, further comprising:
identifying one or more informative fetal loci, each of which is homozygous in the pregnant female subject for a corresponding first allele and which is heterozygous in the fetus for the corresponding first allele and a corresponding second allele;
filtering the one or more informative fetal loci to identify one or more filtered informative fetal loci:
that are located within an expressed region of the reference sequence,
at which at least a first predetermined number of reads in the plurality of reads containing the corresponding first allele are located, and
at which at least a second predetermined number of reads in the plurality of reads containing the corresponding second allele are located,

for each of the filtered informative fetal loci:
determining a first number of reads located at the filtered informative fetal locus and containing the corresponding first allele,
determining a second number of reads located at the filtered informative fetal locus and containing the corresponding second allele,
calculating a sum of the first number and the second number,
calculating a fetal ratio of the second number divided by the sum,
determining a scalar representing a total expression at the filtered informative fetal locus relative to expression of the corresponding second allele in the fetus;
multiplying the fetal ratio by the scalar to obtain a fetal contribution, and

determining a portion of RNA in the sample that is of fetal origin, wherein the portion is the average of the fetal contributions for the filtered informative maternal loci and the filtered informative fetal loci.