The main factor influencing sex determination of an embryo is the sex-determining region Y (SRY), a master regulatory gene located on the Y chromosome. The presence of SRY causes the bipotential gonad to differentiate into a testis. However, some individuals carry a Y chromosome but are phenotypically female (46,XY females) or have a female karyotype but are phenotypically male (46,XX males). 4...

Cytogenetic studies from case 1 included cultures of peripheral blood and skin fibroblasts. Karyotypes from both cultures showed trisomy D(47,XX, + D). Giemsa banding of cells from the skin fibroblast culture, using a modification of the method of Seabright (1971), showed 47,XX,+ 13 (Fig. 3). Chromosome analysis of peripheral leucocytes of the parents were normal. In case 2 the karyotype from a...

We critically examine the possibility of determining the parity of the Θ + (1540) from the reactions N N → Θ + Y (Y = Λ, Σ) recently discussed in the literature. Specifically, we study the energy dependence of those observables that were suggested to be the most promising ones to unravel the parity of the Θ + , namely the spin correlation coefficient A xx , and the spin transfer coefficient D x...

background: division of human genetics (dhg) is a referral center for karyotyping and counseling to the couples as well as to the individuals referred with bad obstetric history and infertility. materials and methods: from 1972 to 2003, overall 1666 couples and 131 female partners with bad obstetric history (boh) such as; spontaneous abortions, live births with congenital malformations and stil...

Background When gonadal sex reversal occurs in mammalian species, the resultant XX males and XY females become infertile or subfertile, suggesting critical roles of sex chromosomes in germ cell differentiation. The objective of our study is to clarify the mechanism of infertility in the B6.YTIR (XY) sex-reversed female mouse, which can be attributed to a failure in the second meiotic division i...

To investigate the mechanism of sex determination in the germ line, we analyzed the fate of XY germ cells in ovaries, and the fate of XX germ cells in testes. In ovaries, germ cells developed according to their X:A ratio, i.e., XX cells underwent oogenesis, XY cells formed spermatocytes. In testes, however, XY and XX germ cells entered the spermatogenic pathway. Thus, to determine their sex, th...

This paper addresses the problem of generating strong convex relaxations of Mixed Integer Quadratically Constrained Programming (MIQCP) problems. MIQCP problems are very difficult because they combine two kinds of non-convexities: integer variables and non-convex quadratic constraints. To produce strong relaxations of MIQCP problems, we use techniques from disjunctive programming and the lift-a...

Mutations in the genes ovo or otu can cause abnormal proliferation of XX germ cells, which leads to so-called ovarian tumors, or they can lead to the elimination of XX germ cells, such that adult females possess empty ovaries. Males carrying ovo or otu mutations are unaffected. To find out when this sexual dimorphism affects germ cells, we analyzed the requirement of embryos and larvae for zygo...

In Caenorhabditis elegans the two sexes, hermaphrodites and males, are thought to be irreversibly determined at fertilization by the ratio of X chromosomes to sets of autosomes: XX embryos develop as hermaphrodites and XO embryos as males. We show instead that both sex and genotype of C. elegans can be altered postembryonically and that this flexibility requires sexual reproduction. When grown ...