DNA Testing With Hair
We are often asked if a paternity test with hair? The simple answer is “Yes.” Often an suspected father, mother, or adult child may want to perform a paternity test with hair, when the other party refuses to perform a paternity test, or they want to do DNA testing in a more discreet manner.
A paternity t est, sibling DNA test, grandparent DNA test, and avuncular DNA test can all be done using hair, and other non-standard samples. However, just submitting hair does not guarantee that the hair specimen will be able to have enough DNA to create the necessary genetic profile.
So if you are thinking about using hair for DNA testing, here is information that is important to know.
How much hair is needed for a DNA test?
In order to do a hair DNA test, the lab will need between 7 to 10 individual strands. These strands must have the hair follicles (roots)intact. The hair stands should always be removed from a brush or comb by the person sending the hair for examination. We strongly recommend that the hair be placed in a regular paper envelope for storage at room temperature. Any type of item that is being studied for genetic testing should never be placed in a plastic baggie, as bacteria can more easily form in that type of environment. Securely storing the item(s) in a paper envelope allows it to “breathe” while protecting it. This allows for the greatest possibility of success.
TV shows like CSI show DNA from any piece of hair. Why can’t I use hair that is cut?
Some shows make great entertainment, but are not always practical in real life.
Hair is composed of a protein known as Keratin. The structure of the hair is composed of three layers as follows:
Hair color is due to specific pigments including melanin. The absence of pigment makes hair white. The structure of the actual hair strand does not contain any cells. Nucleated DNA, the DNA necessary for a paternity test is only found in the root of the hair and not in the shaft. Therefore none of the above layers contain the DNA required for a paternity test.
How can I tell if the root is still attached?
You will need to closely examine the hair strand. It can be seen as a small bulb at the end of the hair. You may need to check using glasses or a magnifying glass if you are uncertain. We lose about 100 hairs every day just from our scalp, however, we do not shed them with the root attached.
Since the hair specimens are collected at home, with no objective proof of who they came from, results of this type of DNA tests cannot be used in court. That does not mean the findings of the DNA test are no accurate. On the contrary, once a DNA profile is generated, our results are 100% accurate. It only means the report is not likely to be accepted in court.
Step-by-step instructions for collecting hair for DNA:
- If you are collecting the hair from a brush or comb, make certain the roots are attached. If you are obtaining them directly from a person, pull seven – ten hairs from the head, eyebrow, underarm, or pubic area.
- Use tweezers to grasp the hair. If pulling from the head, the hairs can be pulled out with one quick, swift motion. Try to pull thicker hairs if possible.
- NEVER touch the end of the hair where it was attached tithe skin (the hair root). The hair root (small clump of skin cells) must be attached to the end of the hair after it is pulled from the brush or body. Please ensure the hair did not break, but was pulled out completely.
- Remember not to touch this end of the hair. Use latex gloves if they are available. Place the hair into a paper envelope. Label the envelope with the date and the name of the person (however you want to identify the sample, as long as you know whose hair specimen it is.
Hair in a paper envelope, stored at room temperature, can last for a long time, sometimes even years. Do not let anything come in contact with the hair to maintain the highest chance of viability.
Once the hair sample is received at the lab, a viability test will be conducted. From the viability test a DNA profile will be developed and compared to one or mother other individuals. Hair DNA testing can be done for one person, or for everyone being tested. Most labs will charge an additional fee per non-standard samples as additional work will be done.