A research team formed by Sander van Doorn (Santa Fe Institute, USA) and Mark Kirkpatrick (University of Texas at Austin, USA) suggests an answer to the puzzle of why sex chromosomes evolve so rapidly. In a theoretical study published in the October 17, 2007 issue of NATURE they demonstrate that sexual conflict can establish novel sex-determining genes and sex chromosomes. The proposed mechanism extends the established theory on the origin of sex chromosomes, and it explains how sex determination can move from an ancestral sex chromosome to an autosome, a non-sex-chromosome, that then invades to become a new sex chromosome.
The mechanism suggested by these authors begins with an autosome that carries two genes with particular features. One of these two genes is under sexually antagonistic selection. This means that some versions of the gene (alleles) are more beneficial in males than in females, while other alleles are more beneficial for females. The other gene influences the sex of the individual. Natural selection produces an association between the two genes – an allele that is most beneficial in males will occur most often with the allele of the other gene that makes the individual male. It is then possible that this new male-making, male-benefiting (or female-making, female-benefiting) combination of genes spreads through the population, eventually replacing the old pair of sex chromosomes.
Genes with sexually antagonistic fitness effects and mutations that influence sex determination appear to be common in nature, but how would we know if the model presented here actually caused a change in the sex-determination mechanism in a particular species" One possible test would look at sexually antagonistic genes on a chromosome immediately before and after that chromosome took over the role of sex determination. This might be possible by comparing closely related species with different sex chromosomes. One species would have a very young set of sex chromosomes, while the other would still use the old sex chromosomes, and might approximate the state of the chromosome right before the switch.
G.S. van Doorn | EurekAlert!
Research team creates new possibilities for medicine and materials sciences
22.01.2018 | Humboldt-Universität zu Berlin
Saarland University bioinformaticians compute gene sequences inherited from each parent
22.01.2018 | Universität des Saarlandes
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
22.01.2018 | Materials Sciences
22.01.2018 | Earth Sciences
22.01.2018 | Life Sciences