Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sex hormone signature indicates gender rather than just chromosomes

18.10.2007
Help with assigning gender could one day be at hand for intersex individuals whose genital phenotypes and sex chromosomes don't match, thanks to the discovery of a stable sex hormone signature in our cells.

In an article published today in the online open access journal BMC Genomics, researchers have shown for the first time that testosterone leaves an irreversible molecular signature in cells that may provide a far more sophisticated way to look at sex than just ascertaining the presence of the Y chromosome. A team of researchers from the US and Germany were able to pinpoint the role of testosterone by comparing individuals with complete androgen insensitivity syndrome (CAIS) to people without CAIS. The findings provide a platform for future work that may lead to improved counselling for those whose gender is ambiguous.

Lead researcher, Professor Paul-Martin Holterhus, of University-Hospital Schleswig-Holstein, Kiel, Germany, said: "Androgens have long lasting effects during certain sensitive stages of our genital development and this is probably true for other organs". He adds "It is currently increasingly accepted that the brain shows sex-specific development in response to presence or absence of testosterone. This affects sex specific behaviour and probably modulates gender identity."

The role of androgens - especially the male-defining hormone testosterone - in sexual development has long been known. Gender programming begins in the embryo and is thought to continue throughout life, particularly during puberty. However, what's not currently known is the different roles of sex chromosome genes versus the long-term programming effects of sex hormones, namely androgens.

Individuals with CAIS, which affects 1 in 20,000 people, look like normal females. But at a genetic level CAIS women have XY sex chromosomes rather than the usual XX. The condition is due to mutations in the gene coding for the androgen receptor, which means that androgen signalling doesn't work: it essentially knocks out the effect of testosterone. The researchers used skin biopsies of external genitalia to compare the gene expression of normal males and CAIS females. Analysis revealed that between males and females, 440 genes differed in their level of transcription. The activity levels of these genes form a 'signature' that they used to evaluate partial androgen insensitivity syndrome (AIS) samples and could be developed to help understand more about individual AIS cases.

"Since we compared XY females with the XY males, the difference can only be explained by differences in androgen action and not by differences in sex chromosomes," explains Professor Holterhus. "Another intriguing observation is that the one normal female (with a 46,XX genotype) in our study did not differ a lot with respect to the identified genes from the XY females. This is an important reassurance for XY females because it limits the role of the sex chromosomes in gender assignment."

Charlotte Webber | alfa
Further information:
http://www.biomedcentral.com/bmcgenomics/

Further reports about: Androgen CAIS Chromosome Gender Sex Signature effect hormone testosterone

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>