Mitotree preprint offers a universal human mitochondrial reference phylogeny at ten times previous resolution

A preprint posted to bioRxiv introduces Mitotree, a new reference phylogeny for human mitochondrial DNA (mtDNA) that the authors describe as a successor to PhyloTree — the community standard resource that was retired in 2016.

PhyloTree version 17 contained approximately 24,275 sequences and 5,438 branches. Mitotree is built from hundreds of thousands of currently available sequences and achieves approximately ten times the haplogroup resolution of its predecessor. The authors also describe scalable computational methods capable of handling datasets of this size, addressing a recognised bottleneck in the field.

Mitochondrial DNA is maternally inherited and does not undergo recombination, making it a tractable system for tracing matrilineal ancestry and inferring population history. All living humans trace their mtDNA to a common female ancestor estimated to have lived approximately 145,000 years ago in Africa. Reference phylogenies underpin haplogroup assignment, population-genetic inference, forensic genetics, and direct-to-consumer ancestry testing.

For researchers working in population genetics, archaeogenomics, or genetic genealogy, Mitotree addresses a practically important gap left by PhyloTree's retirement. Genealogists with an interest in mitochondrial ancestry testing will recognise the significance of an updated, high-resolution reference tree for interpreting haplogroup assignments.

This study is a preprint and has not yet been peer-reviewed.