The pattern of neutral molecular variation under the background selection model. Molecular Breeding 9 : — Of mice and rats: key species variations in the sexual differentiation of brain and behavior. In normal men sexual activity does not correlate with testosterone levels Park and Rissman, Likelihood trees were determined for bp windows with a 10 bp slide between each window.
Induction of reversal in sex differentiation of YY zygotes in the medaka, Oryzias latipes. Furthermore, although chromosomal elements Muller A—F are highly conserved within the order Diptera, parts or all of the 6 elements are used as sex chromosomes across the order, with transitions—wherein sex determination transitioned from one element to another—occurring even within taxonomic families Vicoso and Bachtrog ; Blackmon and Demuth a.
Chi-squares tests corrected for a small n were used for differences in the number of trials in which males ejaculated. Background matters: the effects of estrogen receptor alpha gene disruption on male sexual behavior are modified by background strain. The C repeat from the M.
The human sex chromosomes, a typical pair of mammal allosomes, determine the sex of an individual created in sexual reproduction. Accordingly, the platypus sex-determining gene remains unknown Grafodatskaya et al.
The evolution of sex chromosomes has attracted much interest over the century since Muller proposed that the X and Y evolved from an homologous pair of autosomes. The DNA sequence of the human X chromosome. Strong conservation of the bird Z chromosome in reptilian genomes is revealed by comparative painting despite million years divergence.
CGH on male preparations from karyomorph G unmasked a clear male-specific region covering the short arms of Y 1 chromosome Figures 3U—X.
The identification of different types of heterochromatin on the X  and of important boundary elements  has highlighted suggestions that control of inactivation may occur at both the gene-specific level and the level of chromosomal domains  , . More recently, high density genetic mapping of the papaya genome revealed severe recombination suppression at a sex determination locus [ 7 ].
Male mice with two X-chromosomes are faster to attain ejaculations than males with one X-chromosome. As can be seen, the terminal branches for the O.