In line with a higher mitochondrial content in type I fibers, there was a lower expression of several mitochondrial matrix proteins: enoyl acyl carrier protein reductase, 3-oxoacid CoA-transferase 1, enoyl-CoA delta isomerase 1, hydroxyacid-oxoacid transhydrogenase, and acetyl-CoA synthetase 2 (GO:0005759, q=0.004) in women with PCOS. Here, ECI1 is linked to polycystic ovary syndrome.