1. Medical Research Council/University of Cape Town Research Unit for Molecular Reproductive Endocrinology (Y.-M.S., R.P.M.), University of Cape Town, Observatory 7925, South Africa
2. Division of Molecular Medicine, Department of Medicine, Cornell University Medical College (H.H., M.C.G.), New York, New York 10021
3. Department of Biochemistry, University of Cape Town (N.I.), Rondebosch 7700, South Africa