Can One Carry Out Dna Testing With Hair?

By Author: Glenn Farrier
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Forensic analysis makes it possible to carry out DNA testing with hair. There are obviously a range of other DNA samples you can use, some might be better and some might be worse but the most important thing when providing hairs for a paternity test is that the hairs have root attached.

MtDNA and Nuclear DNA in hair

The hair is divided into 2 parts- the hair root or follicle which is located below the surface of the skin and the hair shaft, the part of the hair which grows above the skin. Both these parts of the hair contain DNA but the DNA in each of these parts is different. The hair shaft contains what is known as mitochondrial DNA- this type of DNA is found in a structure within the cell known as the cell mitochondria. Mitochondrial DNA has very limited uses in DNA testing and can, in fact, only be used to determine maternal lineage. For any other DNA test, including paternity testing, scientists require the DNA found in the cell nucleus. For DNA testing with hair , you will have to provide a minimum of 4 hairs with their root. If you located the right hairs (perhaps examined then with a magnifying glass to ...
... confirm the presence of the follicle) you may put them in a paper envelope and store them in a dry place till you send them off to the laboratory.

Blood DNA test vs Hair

Hair DNA is not the ideal sample to use but offers a relatively good success rate of around 65%. A blood DNA test is far more accurate, especially if taken by medical blood draw - but postage and transport of blood will be a big hassle. The blood will need to be declared pathogen free, packed in special packaging and even then it might be stopped at customs. Also, a further issue is the innate fear of needles that many children and some adults have.

When providing a hair sample for paternity testing, the state of preservation of the hair is important. This is impossible to determine by simply looking at the hair but you will likely have an idea of how old the hair actually is. The older the hair sample, the lower the chances of success. Moreover, normally it is only hairs the have been pulled out from the scalp or other parts of the body that are suitable for the test. Unfortunately, hair on a waxing strip cannot be used, despite them having the hair root. This is due to the various chemicals on the waxing strip.

How to analyze hair DNA?

Hair DNA is analyzed using an advanced DNA amplification and replication method known as polymerase chain reaction or PCR in short. Hair analysis will involve extracting the DNA from the cell nucleus by rupturing the cell. Once the DNA profile is extracted, the results of the test can be issued after scientists compare the DNA profiles of the people taking part in the test.

DNA testing with hair is just one of the many samples you can test. Many more samples can be used so you might want to consider other options.

Karl McDonald specializes in writing articles about forensic DNA sampling. The author focuses on a range of related topics such as DNA testing with hair and blood DNA testing. Many of the articles written by Karl McDonald can be found online.