Mitochondrial genes mtNd4l, mtNd5, mtAtp6 and mtRnr1 as well as nuclear genes Gja1 and Sfrp4 showed similar expression in both controls and lean PCOS groups, and Xrcc1 showed a trend in lower abundance that did not reach statistical significance (Data not shown). Here, SFRP4 is linked to polycystic ovary syndrome.