Cell-free DNA screening is known as a non-invasive prenatal screening method with no risk of miscarriage, with a high disease detection rate and low false positive and false negative rates compared to traditional serum screening methods.

Fingerprints have been used for over 2000 years. They have been extensively studied by anthropologists and biologists. A person's fingerprints begin to form around the 13th week of pregnancy and are completed around the 19th to 24th week. Fingerprints are unique, difficult to change, and remain relatively stable throughout a person's life. They represent a person's basic characteristics.

DNA fingerprints can be used to determine blood relationships, track down criminals through biological traces containing DNA left at the scene, or track down victims through living bodies, even if they are just bone fragments or teeth. This is a great advancement in forensic science.

Mutations in mitochondrial DNA can cause many serious diseases and are inherited through the maternal line. Recently, doctors in the field of preventing the transmission of disease-causing mtDNA mutations have successfully researched and created a baby with three parents using the technique of replacing mitochondria in cells combined with artificial insemination.

The normal human chromosome set has 46 chromosomes divided into 23 pairs. Any change will lead to a chromosomal abnormality. The cause of this condition is usually due to problems arising during the division of gametes or mutations caused by radiation or chemicals. Chromosomal mutations can change the number or structure of chromosomes in a cell.