Sex discriminating genetic markers are commonly used to facilitate breeding programs in economically and ecologically important animal and plant species. However, despite their considerable economic and ecological value, the development of sex markers for kelp species has been very limited. In this study, we used the recently described sequence of the sex determining region SDR of the brown algal model Ectocarpus to develop novel DNA-based sex-markers for three commercially relevant kelps: Laminaria digitata , Undaria pinnatifida and Macrocystis pyrifera. Seven primer pairs corresponding to three loci in the Ectocarpus SDR amplified sex-specific bands in the three kelp species, yielding at least one male and one female marker for each species. Our work has generated the first male sex-specific markers for L.
Fetal sexual differentiation relies on the translation of chromosomal sex established at fertilization into gonadal sex and somatic sex as development proceeds. In cases where chromosomal, gonadal, and somatic sex are incongruent in human infants and children, rapid establishment of the diagnosis and implementation of medical and surgical management is of paramount importance, since the gender identity is so important to the psychological well-being throughout life. This work was done in order to test the value of PCR technique for rapid sex determination compared to classic cytogenetic technique. Subjects included 20, cases including 10 neonates with ambiguous genitalia, 2 adult females with delayed puberty and 8 adult males with infertility, in addition to 20 normal infants of both sexes as a control group. The diagnosis of sex was attempted through examination, cytogenetic study, ultrasonography, gonadal biopsy and hormonal analysis, in addition to PCR amplification for the detection of SRY and ATL1 gene loci on Y and X chromosomes respectively. We concluded that PCR as a simple, rapid and reliable technique can complement and also confirm cytogenetic studies in the diagnosis of sex in cases of sex chromosome disorders.
Investigating fetal development in mice necessitates the determination of fetal sex. However, whilst the sex of adult and juvenile mice can be readily distinguished from anogenital distance, the sex of fetal and neonatal mice cannot be identified visually. Instead, genetic sex must be determined by PCR amplification of X chromosome genes with divergent Y chromosome gametologs. Existing simplex PCR methods are confounded by small size differences between amplicons, amplification of unexpected products, and biased amplification of the shorter amplicon.