mtDNA haplogroups

Haplogrep

Because mtDNA is inherited maternally and without recombination, its variants reveal a lineage. These lineages form a branching tree with regional main clades. Genome assigns the sample to a branch.

mtDNA TREE · SIMPLIFIED L L3 N R mt-MRCA AFRICA · BASE L0 L1 L2 L3 ASIA · AMERICAS M C D G Z A B F EUROPE · WEST EURASIA H V J T U K Haplogrep assigns the sample to a branch of PhyloTree.

How the tree is built

Because mtDNA does not recombine, mutations accumulate along a lineage and are passed on. Shared mutations define common branches. PhyloTree captures this structure as a reference against which individual samples are placed.

How Genome analyses

Genome uses Haplogrep, which compares the sample's mtDNA variants to the PhyloTree and returns the best-matching branch with a quality score. The haplogroup report leads with a short conclusion, separates ancestry from disease and protection context, and explicitly marks population statements that are not supportable.

What Genome measures. The sample's mitochondrial haplogroup with a quality measure, determined from the pattern of mtDNA variants against the reference tree.

Related topics

mtDNA variantsY haplogroup

Sources

  1. 1Weissensteiner et al., 2016 HaploGrep 2: mitochondrial haplogroup classification in the era of high-throughput sequencing. Nucleic Acids Research 44:W58–W63. doi.org/10.1093/nar/gkw233
  2. 2van Oven & Kayser, 2009 Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation (PhyloTree). Human Mutation 30:E386–E394. doi.org/10.1002/humu.20921