1. Andrology Unit (C.G., F.N., I.L., F.D., G.F., C.K.), Department of Clinical Physiopathology, University of Florence, Florence 50139, Italy
2. The Wellcome Trust Sanger Institute (D.J.T., Y.X., C.T.-S.), Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, United Kingdom