American Society of Hirudotherapy

Phylogeny and phylogeography of medicinal leeches (genus Hirudo): fast dispersal and shallow genetic structure

Phylogenetics article published in Molecular Phylogenetics and Evolution (2012)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Genomics & ProteomicsTrontelj P, Utevsky SY · Molecular phylogenetics and evolution, 2012

Abstract

Medicinal leeches (Hirudo spp.) are among the best-studied invertebrates in many aspects of their biology. Yet, relatively little is known about their biogeography, ecology and evolution. Previous studies found vast ranges but suggested low genetic diversity for some species. To examine this apparent contradiction, the phylogeny and phylogeography of the widespread Hirudo verbana, Hirudo medicinalis and Hirudo orientalis were investigated in a comparative manner. Populations from across their ranges in Europe, Asia Minor, the Caucasus and Central Asia, were analyzed by various phylogenetic and population genetic approaches using both mitochondrial (COI and 12S) and nuclear DNA sequences (ITS1, 5.8S and ITS2). The populations showed surprisingly little genetic differentiation despite vast ranges. The only clear structure was observed in H. verbana. This species is subdivided into an Eastern (southern Ukraine, North Caucasus, Turkey and Uzbekistan) and a Western phylogroup (Balkans and Italy). The two phylogroups do not overlap, suggesting distinct postglacial colonization from separate refugia. Leeches supplied by commercial facilities belong to the Eastern phylogroup of H. verbana; they originate from Turkey and the Krasnodar Territory in Russia, two leading areas of leech export. H. verbana and H. medicinalis have experienced recent rapid population growth and range expansion, while isolation by distance has shaped the genetic setup of H. orientalis. The habitat of the latter is patchy and scattered about inhospitable arid and alpine areas of Central Asia and Transcaucasia. Centuries of leech collecting and transport across Europe seem not to have affected the natural distribution of genetic diversity, as the observed patterns can be explained by a combination of historical factors and present day climatic influences.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticleResearch Support, Non-U.S. Gov't
Indexed MeSH termsAnimalsBase SequenceBiological EvolutionDNA, IntergenicDNA, MitochondrialDNA, RibosomalGenetic DriftGenetic VariationGenetics, PopulationHirudo medicinalisMolecular Sequence DataPhylogeny

Summary

Combined mitochondrial (COI, 12S) and nuclear (ITS1, 5.8S, ITS2) phylogeography reveals shallow genetic differentiation across vast Hirudo verbana, H. medicinalis, and H. orientalis ranges; commercial leeches originate predominantly from Turkey and the Krasnodar Territory.

Why This Matters for Hirudotherapy

This study investigated the phylogeny and phylogeography of three medicinal leech species — Hirudo verbana, H. medicinalis, and H. orientalis — using mitochondrial (COI, 12S) and nuclear DNA sequences across their ranges in Europe, Asia Minor, the Caucasus, and Central Asia. The authors found surprisingly little genetic differentiation despite vast ranges, with the only clear structure being Eastern and Western phylogroups in H. verbana, and noted that commercial leech supplies belong to the Eastern phylogroup originating from Turkey and the Krasnodar Territory. This is indirectly relevant to ASH as it informs understanding of the genetic diversity and sourcing of medicinal leech species used in therapy. The caveat is that this is a pure taxonomy/biogeography study with no direct clinical or therapeutic content.

Citation

Phylogeny and phylogeography of medicinal leeches (genus Hirudo): fast dispersal and shallow genetic structure.

Trontelj P, Utevsky SY · Molecular phylogenetics and evolution, 2012

Added to ASH library: May 26, 2026 · Site last updated: June 18, 2026

This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.