Mitochondrial DNA 4977 bp Deletion in Peripheral Blood is Associated with Polycystic Ovary Syndrome.

Background: PCOS is a common worldwide endocrine disorder. We aimed to examine the associations of two mtDNA biomarkers in the peripheral blood, mtDNA CN and mtDNA 4977 DR, with PCOS in a clinical setting. Methods: We performed a study involving 263 women with PCOS and 326 age-matched controls between January 2016 and December 2018. The mtDNA CN and mtDNA 4977 DR were measured via a multiplex probe-based qPCR. The associations of mtDNA CN and mtDNA DR with the risk of PCOS were estimated by logistic regression. Results: In the analysis between mtDNA biomarkers and PCOS, the mtDNA CN ( P = 0.003) and mtDNA 4977 DR ( P < 0.001) levels in PCOS patients were significantly higher than those in the controls. After adjusting for BMI, LH/FSH, and T, only higher mtDNA 4977 DR was associated with PCOS (odds ratio 1.053, 95% confidence interval 1.024 to 1.083, P < 0.001). The linear dose-response trends of mtDNA 4977 DR were also supported by the quartile analyses. Conclusions: Multivariable models suggest that mtDNA 4977 DR levels are strongly associated with PCOS and represent an independent risk factor for PCOS. Future investigation of the utility of mtDNA as a biomarker for PCOS is warranted.