Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Iberia was the European demographic reservoir during the last Ice Age

13.01.2005


By studying mitochondrial DNA, which is passed from mother to child, researchers have found that most of the actual European inhabitants seem to have come from re-expansion of hunter-gatherers populations, which have migrated from Iberia, Europe after the end of the last Ice Age reports an article in the January issue of Genome Research.

In the study of human evolution through history and pre-history there are now two indispensable sets of genes to follow: Y-chromosome and mitochondrial DNA (mtDNA) genes. Both sets are transmitted uniparentally from one generation to the next - father to son in the case of the Y-chromosome and mother to child in the case of mtDNA - which makes them especially useful to trace lineages.

Mitochondrial DNA is a circular structure composed of 13 genes and exists, as the name indicates, in mitochondria, which are organelles responsible for energy production in the cell. Mitochondrial DNA sequences can be divided in different groups – haplogroups – according to genetic variations (or polymorphisms). Each haplogroup can then be divided into sub-clades (or sub-groups) according to further polymorphisms. Because it is possible to calculate the changes occurring in mtDNA in a certain period of time (the rate of change is constant and known) it is possible to follow in time the different sub-clades and learn when they did get separated, and consequently their individual migrations/geographical separations.



And in fact, the study of mtDNA haplogroups has been used to understand better the migrations of human population throughout evolution. Unfortunately, this has not been possible in Europe, although some progress has been made on a relatively rare haplogroup V. But around half of the European mtDNA sequences belong to a haplogroup (H) and so far it had been impossible to understand its evolutionary pathway in the continent.

But now Luísa Pereira, Martin Richards, Ana Goios, Vincent Macaulay, António Amorim and colleagues from Spain, Israel, Russia, Germany, Dubai, Czech Republic and Ireland, taking advantage of recently available information on haplogroup H polymorphisms, decided to make a new attempt to understand the European migrations throughout evolution. The team of scientists analysed 649 individuals of the H haplogroup from 20 populations throughout Europe, Caucasus and the near East and, by managing to trace the localisation of the different sub-clades, were able to further resolve the evolutionary (and migrational) history of haplogroup H and modern Europeans.

In fact, it is believed that haplogroup H evolved in the Near East around 28.000-30.000 years ago and spread throughout Europe 20.000 years ago. Although it was thought that some, or all, of the European population of this haplogroup have re-expanded throughout the continent from a European glacial refuge 15.000 years ago, this was not possible to be confirmed. Now Pereira, Richards, Goios, Macaulay, Amorim and colleagues’ work not only confirms that in fact the oldest lineage of H (called H*) was found in the near East and entered Europe during the peak of the last Ice Age, but also claims to have identified the glacial refuge in Europe from where humans re-expanded as Iberia.

Pereira, Richards, Goios, Macaulay, Amorim and colleagues’ work is important for the history of human evolution suggesting that most modern Europeans evolved from hunter-gathers that expanded at the end of the last Ice Age (end of the Palaeolithic) from a glacial refuge in Iberia where they have stayed for around 10,000 years after an initial migration from the Near East.

Piece researched and written by: Catarina Amorim ( catarina.amorim@linacre.ox.ac.uk)

Catarina Amorim | alfa
Further information:
http://www.genome.org/cgi/content/abstract/15/1/19?ct

More articles from Life Sciences:

nachricht Nerves control the body’s bacterial community
26.09.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Ageless ears? Elderly barn owls do not become hard of hearing
26.09.2017 | Carl von Ossietzky-Universität Oldenburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The fastest light-driven current source

Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond ¬¬ – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.

Graphene is up to the job

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Nerves control the body’s bacterial community

26.09.2017 | Life Sciences

Four elements make 2-D optical platform

26.09.2017 | Physics and Astronomy

Goodbye, login. Hello, heart scan

26.09.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>