The following excerpt is from an article in the November 9, 2009 edition of Law Times by Canadian Rosalind Conway. If this interests you, be sure and read the full article. There’s a lot more to it. Interesting stuff…
Nuclear DNA can provide a veritable match to a suspect, but mitochondrial DNA is a relatively new phenomenon in Canadian courts.
Known as mtDNA, it’s the genetic material found in the mitochondria of cells rather than the nucleus.
MtDNA has been used in anthropological and genealogical studies as well as after 9-11 and to examine the remains of Czar Nicholas II. Still, its use in American courts is controversial.You inherit mtDNA maternally. Absent genetic mutations, a mother’s mtDNA passes on to her children. As a result, they have the same mtDNA as their maternal relatives.
A rootless hair may have degraded DNA that cannot yield a nuclear DNA profile. But mtDNA is available in great numbers in the cell, meaning the profile of the evidentiary sample may be available.
The mtDNA test result reveals markers or nucleotides and ultimately a profile or what’s called a haplotype. This profile is compared with those in a databank created by the FBI in the United States.
The Scientific Working Group on DNA Analysis Methods database contains 4,839 convenience samples collected in a non-random manner from FBI agents, paternity suit samples, and other sources.
The FBI database contains 1,655 Caucasians, 1,148 African-Americans, and 686 people of Hispanic descent. About half the haplotypes appear only once, but that still makes it difficult to tell if they are rare because the databank is so small.
