Can saliva be used for paternity testing?

A paternity test is a medical test done to determine blood relationships. It is a test that is performed in many separated families or when there is a legal need. There are many samples that can be collected for personal identification, such as hair, bloodstains, and oral mucosa, all of which can be used for paternity testing. However, saliva, as a body fluid, is generally not used as a sample for paternity testing!

1. Hair Collection

Have a blank sheet of paper ready.

Pull out a hair from your head (quickly, preferably two at a time), and observe with the naked eye whether there is a translucent capsule-like object at the root of the hair. Do not touch the hair follicles with your hands. Wrap the removed hair with A4 paper and put it in an envelope. Mark the identity and name of the person to whom the sample belongs on the surface of the envelope. Each person needs 15-20 sticks.

2. Bloodstain Collection

Use a needle to lightly prick the skin surface (fingertips, earlobes, heels and any part of the body surface). When the blood flows out, gently wipe it with the prepared gauze (available at large and small pharmacies), leaving 5-6 blood marks the size of soybeans on the surface.

Wrap it in white paper or an envelope, not in a plastic bag. Mark the surface of the envelope with the identity and name of the person to whom the sample belongs. Note: The person whose blood is collected must not have received blood from others within six months and must not have undergone a bone marrow transplant within two years.

3. Oral mucosa collection

Basic hygiene conditions for collecting samples: clean hands, new oral cotton swabs (single-headed cotton swabs sold in pharmacies), and clean envelopes.

1. First, mark the clean paper envelope with the sample collection date, sample identity (e.g., father, mother, child, etc.) and name or code.

2. Use a cotton swab to reach into the child's mouth, and gently scrape the sides of the mouth (inner cheeks, cheeks) and under the tongue with the cotton swab. Gently rotate or scrape about 10 times before removing it. Repeat 3-5 times.

Note: During the collection process, please do not touch the cotton ball part of the oral swab with your hands. Please rotate and brush it with a little force to ensure that enough DNA is obtained.

After collection is completed, it can be directly packaged in a breathable paper envelope (the breathable envelope will dry naturally in the shade). (Plastic bags cannot be used because they are airtight and will cause the samples to mold or stink, degrade DNA, and affect the experiment. Unless some special samples need to be stored in a refrigerator, daily samples can be packaged in breathable envelopes.)

Note: Please do not make a mistake with the sample, please make sure the sample is the same as the person marked on the packaging envelope.