These scientists identified a subpopulation of beef cows that contain excess intrafollicular androstenedione (A4), theca molecular phenotypes (greater mRNA abundance CYP17A1, CYP11A1, GATA6, and LHCGR) similar to women diagnosed with PCOS and subfertility, with a 17% reduced calving rate (Summers et al., 2014). This evidence concerns the gene CYP17A1 and polycystic ovary syndrome.