Genetic recombination, the process by which sexually reproducing organisms shuffle their genetic material when producing germ cells, leads to offspring with a new genetic make-up and influences the course of evolution.
In the current issue of Nature, researchers at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, and the EMBL-European Bioinformatics Institute (EMBL-EBI) in Hinxton, UK, present the most precise map of genetic recombination yet. The study sheds light on fundamental questions about genetic shuffling and has implications for the tracking of disease genes and their inheritance.
In order to generate germ cells, sexually reproducing organisms undergo a complex series of cell divisions (meiosis) that includes the shuffling of genetic material inherited from the two parents. Equivalent chromosomes from mother and father pair up and exchange sections of DNA in a process called crossover. In a different type of recombination, called non-crossover, a small piece of DNA is copied from one chromosome onto the other without reciprocal exchange leading to gene conversion.
Non-crossovers are minute events with a subtler effect than the exchange of larger fragments, but both types of recombination can increase genetic diversity and explain why organisms of the same species differ in many ways. Both types of recombination can also act to separate the transmission of neighbouring genes, which are normally inherited together.
The groups of Lars Steinmetz at EMBL and Wolfgang Huber at EMBL-EBI have produced the most detailed map to date of recombination events in the yeast genome.
“Our map has the highest resolution of recombination events that currently exists for any organism. We can locate crossovers and even hard-to-trace non-crossovers, typically with a precision of about 80 bases. This resolution is 20 times higher than in any existing yeast map and more than 360 times higher than a recent human map,” says Steinmetz.
The map revealed many new insights into the organisation of recombination in yeast. On average over 150 recombination events were observed during a typical meiosis. These events did not occur uniformly across the genome. The recombination rate varied according to location, with events concentrated at so-called hotspots, some of which favoured either crossovers or non-crossovers. The researchers also found evidence for interference between crossovers and non-crossovers - a phenomenon previously only known to occur between crossovers - that makes it unlikely for two recombination events to happen in close proximity.
The fundamental principles of recombination are likely to be shared between yeast and humans. “Our map expands our understanding of crossover and provides a wealth of new information about non-crossovers and gene conversion. It will act as a reference for future research into recombination,” says Richard Bourgon from Huber's group, who developed the statistical methodology for this new type of data.
The insights gained will not only help tackle questions about the basic mechanisms of recombination; they will also have practical implications for the tracking of disease genes in humans.
Anna-Lynn Wegener | alfa
Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München
Second research flight into zero gravity
21.10.2016 | Universität Zürich
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences