This kind of DNA testing studies the mitochrondrial DNA that is sometimes found in a strand of hair.
The hair does need not have the root intact—the shaft itself is adequate.
Unlike regular DNA, which comes from both parents, mitochondrial DNA is passed down from mother to
fetus. Mitochondrial DNA testing recently received wide attention when it was used to analyze
skeletons believed to be the assassinated Romanov family. To learn more about this, be sure to
watch our NOVA program, "Anastasia: Dead or Alive?," which will air on May 21, 1996.
Even though mitochondrial DNA testing is definitive, it is an expensive procedure. More importantly,
the artifacts themselves—hair or bone—are especially susceptible to contamination. This type
of testing tends not to be done on hair, since the quantity of mitochondrial DNA one can collect
from a strand of hair is extremely small.