Polycystic ovary syndrome in mitochondrial disorders due mtDNA or nDNA variants

Objectives: Whether polycystic ovary syndrome (PCOS) is associated with mtDNA or nDNA mutations causing mitochondrial disorders (MIDs) or not is under debate. This review aims at summarising and discussing previous and recent findings concerning the frequency, diagnosis, and treatment of PCOS in MIDs. Methods: Systematic literature review using appropriate search terms. Results: Currently, no reports are available which document a causal relation between PCOS and specific or non-specific MIDs. However, reports about the presence of various mtDNA point mutations, mtDNA deletions, and mtDNA depletion in females with PCOS have been published by a single Chinese group, without being confirmed by other study groups. Arguments against a causal relation between these mtDNA variants and PCOS are that all variants were homoplasmic and that none of the patients carrying any of these variants presented with a phenotype characterised by features other than PCOS or diabetes. Conclusions: Currently, there is no evidence that PCOS is a phenotypic feature of MIDs. mtDNA variants reported by a single centre in association with PCOS need to be confirmed by multicentre studies. In case of hereditary PCOS, whole exome (genome) sequencing is recommended