A maternal haplogroup is a family of mitochondrial DNA (mtDNA) that traces back to a single common ancestor. The Maternal Haplogroup report can shed light on the origins of some of our ancestors and on their migrations over tens of thousands of years.
Your maternal haplogroup assignment is based on your mitochondrial DNA, which you inherited from your mother. The Maternal Haplogroup report tells you about your maternal-line ancestors, from your mother through her mother and beyond. Both males and females inherit their mitochondrial DNA and, therefore, their haplogroup assignment from their mothers. Haplogroups are defined by specific sets of shared genetic variation.
Since members of a haplogroup tend to be found in the same region of the world, your maternal haplogroup can say something about where some of your maternal-line ancestors lived. Geneticists use global haplogroup distributions to trace significant events in human prehistory, such as the migration of people to the Americas or the expansion of agriculture from the Middle East. In many cases we can offer accounts of where and when a haplogroup originated.
Maternal haplogroups begin with a capital letter (occasionally two) that designates a major branch of the mitochondrial DNA tree. That capital letter is often followed by a series of numbers and lower-case letters, each corresponding to a subsequent branch of the tree. Our platform probes single nucleotide polymorphisms (SNPs) that are known to vary from one person to the next. These SNPs, selected because they are common and/or useful in determining your particular haplogroup, include some in the coding region as well as some in the Hypervariable Region. While these SNPs yield a high level of resolution, they are less detailed than full sequencing of all 16,569 base pairs of the mitochondrial genome would be, so this analysis does not include some of the less common mtDNA variation you might have.
If our haplogroup assignment looks different from other assignments you may have received, it may be because different reference trees were used and/or a different set of SNPs were analyzed.