I have performed DNA extraction from hair for forensic purposes and worked fine. I use it from the head which is the zone where collecting hair is less painful for the donor. If not available next zone I would try would be the brows.  Collect the hair one by one, pulling from its base (or the most proximal site to scalp) to a side NOT straight (perpendicularly). This technique will not assure you getting the follicle on the first try (practice recommended) but is less painful. Once you have a hair with follicle, you cut its terminal part as needed. The protocol I use says you should leave 1 cm of hair from its follicle.

For the extraction part, I use chelex extraction (5% chelex 100, boil for 20 min, etc) which gives good results for detection (PCR) purposes. Four or five hairs gives you enough DNA for PCR (for forensic analyses, I usually do not quantify it).     

I have performed DNA extraction from hair for forensic purposes and worked fine. I use it from the head which is the zone where collecting hair is less painful for the donor. If not available next zone I would try would be the brows.  Collect the hair one by one, pulling from its base (or the most proximal site to scalp) to a side NOT straight (perpendicularly). This technique will not assure you getting the follicle on the first try (practice recommended) but is less painful. Once you have a hair with follicle, you cut its terminal part as needed. The protocol I use says you should leave 1 cm of hair from its follicle.

For the extraction part, I use chelex extraction (5% chelex 100, boil for 20 min, etc) which gives good results for detection (PCR) purposes. Four or five hairs gives you enough DNA for PCR (for forensic analyses, I usually do not quantify it).     

Any specific reason why you would want to use hair follicles instead of simply using buccal swabs or saliva?

Hi, Dr. Ochoa-Ramírez, Can you show more details about your method for DNA extraction? I tried some DNA extraction kits, but they are not good for extracting DNA from hair.

Hi Lars-Erik Wehner,

Yes, the virus I work on can also be acquired exogenously, and can be isolated in the saliva/oral cavity, whereas in hair follicles we should only see the endogenous virus.

Thanks,

Adam

Can you explain, how will you expect a viral DNA from hair follicles to see endogenous virus,

Viruses are parasite which is endogenous and dependant on host replication factor, in such case, how could u differentiate exogenous virus and endogenous virus ?

Can you justify it?

Hi Nandagopal,

and endogenous virus is one that has integrated into the host genome, and is replicated alongside that (by the host), independent of the expression if viral factors. The virus has become integrated into the germ-line and thus inherited through generations. 

An endogenous virus can be differentiated through several means. In the case I am looking at (inherited chromosomal integrated HHV-6), we can determine the copies of virus per cell in a DNA sample. If this is the endogenous form we would expect to see integer copy numbers (1, 2, 3 per cell etc,) these  copy numbers are also higher than anything seen in an active infection. Further to this we are wanting to using hair follicles as this is not a site of active replication, or latency of the exogenous form of HHV-6, thus any virus observed should be the endogenous (integrated) form. If you wanted to look deeper at this you could also look for replicating virus (there should  be non) with IHC, in situ hybridisation, and mRNA levels etc; however as we already have data from the blood (to compare viral copy numbers), and have determined the site of integration in the individuals this is not necessary. 

The hair folicles are simply to be used as an easily obtainable source of germ-line DNA to check that results we have obtained from the blood are reflective of the germ-line.

In short, yes we can justify this.

Thanks for your detailed reply, I agree your justification

Dear Xiaomin Xia:

I attach the document from which I took the protocol:

It worked fine for simple purposes (PCR). The only problem with chelex is that you yield single stranded DNA, so any technique that requires double stranded DNA needs any other extraction method.

Best regards 

You may try to do so as the protocol is very common and is widely used in DNA finger printing in forensic science