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MRC Mitochondrial Biology Unit


In a collaborative project led by the University of Cambridge the MitoPhen database has been established under the leadership of Professors Patrick Chinnery and Ernest Turro (now at the Icahn School of Medicine at Mount Sinai, New York, USA).

The MitoPhen database is the result of the curation of the clinical phenotypes of 6688 published individuals with 89 pathogenic mitochondrial DNA (mtDNA) mutations - collating 26,348 human phenotype ontology (HPO) terms.

This enabled a hypothesis-free definition of mtDNA clinical syndromes, an overview of heteroplasmy-phenotype relationships, the identification of under-recognized phenotypes, and provides a publicly available reference dataset for objective clinical comparison with new patients using the HPO.

Studying 77 patients with independently confirmed positive mtDNA diagnoses and 1083 confirmed rare disease cases with a non-mitochondrial nuclear genetic diagnosis, the collaborators have shown that HPO-based phenotype similarity scores can distinguish these two classes of rare disease patients with a false discovery rate of <10% at a sensitivity of 80%.

Enriching the MitoPhen database with more patients will improve predictions for increasingly rare variants.

Full citation: Thiloka E Ratnaike, Daniel Greene, Wei Wei, Alba Sanchis-Juan, Katherine R Schon, Jelle van den Ameele, Lucy Raymond, Rita Horvath, Ernest Turro, Patrick F Chinnery, MitoPhen database: a human phenotype ontology-based approach to identify mitochondrial DNA diseases, Nucleic Acids Research, 2021;, gkab726,