Wnt-4 is present in the gonads of both males and females. After sex
determination, Wnt-4t is downregulated in the gonads of normal males.
However, the expression of Wnt-4 in the adrenal gland is not
sex-specific:
"In contrast to the situation in the gonads, the expression of Wnt-4
in the adrenal gland is independent of sex, being detectable from the
very beginning of the formation of the adrenal cortex and later being
restricted to the outermost cortical region."
University of Oulu: Development of the adreno-genital system
http://herkules.oulu.fi/isbn951426844X/html/i232721.html#I232725
"In addition to their involvement in kidney development we have shown
that Wnt-4 signalling is important for mammalian sex determination.
Wnt-4 is expressed initially in both sexes, but at the stages when the
sex is being specified, Wnt-4 gene expression is shut off in males but
persists in females."
University of Oulu: Seppo Vainio, Ph.D
http://www.oulu.fi/faculties/resea/biocente/bco-hakemisto/bco/research/vainio.htm
"The research Brian [Jordan] reports on in Vienna involves his work on
the sex determination cascade in mammals, 'all of the genes involved
in deciding whether somebody's going to be male or female,' Brian
explains. 'It's much more complicated than just having a Y chromosome
or not.'
One of those genes is WNT-4. Research has shown that when WNT-4 is
missing, female mice develop ovo-testes, the kind of ambiguous sexual
organs characteristic of sexual determination gone awry. Using
preserved DNA from a male infant who had a Y chromosome but ambiguous
sexual organs, Brian found that the boy had too many copies of that
same gene. As Brian explains it, both males and females start out with
almost identical genes. It's the patterns in which those genes are
turned on or off that determine gender. In this case, too much WNT-4
appears to create abnormalities in males, whereas too little creates
abnormalities in females."
UCLA: Brian Jordan - Human Genetics
http://www.gdnet.ucla.edu/asis/profile/hgen.htm]]
"The signalling molecule WNT4 has been associated with female sexual
development in the mouse (Vainio et al., 1999). In the developing
gonad, the Wnt4 gene is expressed in both sexes prior to 11.5 dpc.
After sex determination, expression persists in the XX gonad but is
downregulated in the XY gonad."
University of Edinburgh: Endothelial and steroidogenic cell migration
are regulated by WNT4 in the developing mammalian gonad
http://homepages.ed.ac.uk/hmcqueen/Swain3663.pdf
Google search strategy:
Google Web Search: "wnt-4" + "both sexes"
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22wnt-4%22+%22both+sexes
Google Web Search: "wnt-4" + "both males and females"
://www.google.com/search?hl=en&ie=UTF-8&oe=UTF-8&q=%22wnt-4%22+%22both+males+and+females
I hope this information is useful. If anything is unclear, or if a
link does not function, please request clarification.
Best regards,
pinkfreud |
