• Is it possible to obtain samples from a dead body for the purposes of DNA testing?

Yes it is.  Several types of samples can be collected, including hair with roots, blood or tissue.  Hair samples must be plucked and should be several (7-10 minimum) hairs.  In the case of a body which is decomposed, long bones (humerus or femur) are the recommended samples.  Teeth can also be used.

If the results from this type of testing are needed for legal or court admissible purposes, it is mandatory that a chain of custody be followed.  The samples must be collected by a medical examiner, coroner or other qualified third party.  Otherwise, the results would not be court admissible or qualify for any legal purpose. 

• Are more accurate results obtained from whole blood or blood cards or buccal swabs?

These samples all produce results which are equally accurate.

• Can a DNA profile be obtained from urine? 

Yes. A profile can be obtained from urine.

• Is it possible to detect the presence of semen, blood or sperm on clothing, materials or objects?

It is possible.

• If there is a sample which contains a mixture of male/female, and standard testing did not obtain a male DNA profile, is it possible to obtain a male profile?

A test called Y-STR can be used in these instances.  It is vital however that a minimum amount of male DNA must be present.