Method for detecting fetal copy number variations based on virtual positive and negative data

A computer-readable medium recording a program applied to perform that performs the steps of:

• obtaining sequence information (read) of a plurality of nucleic acid fragments obtained from a biological sample of a pregnant woman with a normal fetus;
• mapping the obtained sequence information to a human reference genome and aligning the sequence information of the nucleic acid fragments to a chromosome;
• calculating the read count (RC), fetal DNA fraction (fetal fraction:
• FF), and GC content of the sequence information of the nucleic acid fragments in the target chromosome in a normal fetus, based on the sequence information of the nucleic acid fragments aligned to the chromosome;
• producing synthetic normal data from normal data based on the read count and fetal DNA fraction in the target chromosome in a normal fetus, wherein the normal data is the read count in the target chromosome site in a normal fetus;
• producing synthetic positive data from the synthetic normal data, wherein the synthetic positive data is the read count in the target chromosome site in a fetus with copy number variations;
• establishing a copy number variation discrimination model from the produced synthetic normal data and synthetic positive data;
• and
• detecting copy number variations of a test sample using the copy number variation discrimination model.