Selection bias at the heterosexual HIV-1 transmission bottleneck by Carlson, J, Schaefer, M, Monaco, D, Batorsky, R, Claiborne, D, Prince, J, Deymier, M, Ende, Z, Klatt, N, DeZiel, C, Lin, T, Peng, J, Seese, A, Shapiro, R, Frater, J, Ndung'u, T, Tang, J, Goepfert, P, Gilmour, J, Price, M, Kilembe, W, Heckerman, D, Goulder, P, Allen, T, Allen, S