PPARGC1A and polycystic ovary syndrome: The cross-sectional study by Zhao et al. (2017) investigated the association between peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPARGC1A) promoter methylation, leukocyte mitochondrial DNA (mtDNA) content, and metabolic risk in 175 women with PCOS compared with 127 healthy controls [25].