Why and how paternal mitochondrial DNA gets cut out of the inheritance.
Level 5 - mechanism / opinion, no new human data
Narrative review of basic mechanistic research across animal species (CEBM Level 5).
PubMed 40674831 · doi:10.1016/j.gde.2025.102381
What was done
Narrative review synthesizing findings across multiple animal species, including humans, regarding the molecular mechanisms and evolutionary rationale behind maternal-only mitochondrial DNA (mtDNA) inheritance. The review compares historical models of egg-mediated post-fertilization organelle destruction via autophagy and ubiquitin-proteasome systems with newly reported pre-fertilization intra-mitochondrial degradation pathways.
What was found
The abstract reports no quantitative data or statistical measures. Conceptually, it describes that paternal mtDNA is actively degraded inside mitochondria independently of and prior to the complete breakdown of the organelle itself, frequently occurring before fertilization.
Why it matters
Shifts the paradigm of mitochondrial inheritance by demonstrating that paternal mtDNA clearance is not solely driven by maternal degradation post-fertilization, but also involves active, early intra-mitochondrial degradation in paternal cells.
Limits
This is a narrative review lacking a systematic search protocol, formal inclusion criteria, or pooled quantitative analysis. The abstract reports no empirical sample sizes, specific effect sizes, or comparative elimination rates across species.
Cited by
- supports Mitochondria and mitochondrial DNA are inherited exclusively through maternal lineage in humans.