What is a known reference sample, and how should it be collected?

A known reference sample is DNA taken directly from a person (i.e. victim or suspect).  A buccal swab is DNA collected from inside a person’s mouth.  To collect buccal swabs, hold the sticks of two sterile swabs together and rub the swab ends along the inside of the person’s cheek and gum area. Allow the swabs to air dry in a swab box or other appropriate container.  Package the dried swabs into a container that is clearly labeled with the person's name. Buccal swabs do not need to be refrigerated. Known reference samples from the medical examiner’s office are typically submitted on a blood card.