After DNA tests on a skeleton found among the remains of an antique Roman house in 2004, Italian scientists assumed they had discovered a breed of horse which had been hitherto unknown or had died out.
An error occurred during these tests, is what a team of scientists from Cambridge University and the Institute of Forensic Genetics at Münster University now say. Their arguments have been published in a letter to the editor of the online edition of the Journal of Cellular Biochemistry. Evidently, donkey DNA became combined with horse DNA, producing an artificial hybrid DNA.
In the original study, analyses were made of five skeletons from equids, to which horses, donkeys and zebras belong. The skeletons had been excavated from the remains of a household in the antique city of Pompeii, in the stables of the Casa dei Casti Amanti (House of the Chaste Lovers). This well-known building is named after the wall frescoes depicting romantic scenes. The owner was probably Caius Iulius Polybius, a wealthy politician and baker. Archaeologists derive this latter occupation from the fact that an open baking oven and four millstones were found in the house. The horse skeletons had been conserved by means of a layer of volcanic ash which had buried Pompeii and the nearby settlement Herculaneum when Vesuvius erupted in 79 AD.
The team of researchers that carried out the original study examined the 2000-year-old mitochondrial DNA of the horses, i.e. DNA not from the cell nucleus but from the “energy powerhouses” (the mitochondria) of the cells. Four DNA types could be easily classified as they matched typical mitochondrial genetic material found in horses. The fifth horse, however, seemed to possess DNA similar to that of horses but otherwise unknown. The scientists came to the conclusion that the horse in question was of a breed hitherto unknown and presumably extinct.
Susan Gurney, a PhD student at Münster University’s Institute of Animal Physiology and a member of the Institute of Forensic Genetics at the University of Cambridge in the UK, took a closer look at the data. Gurney, an expert on the evolution of horses, concluded that an error had occurred in the initial tests. The mitochondrial DNA of a horse had evidently come into contact with that of a donkey, resulting in the formation of hybrid DNA which appeared to originate from an unknown breed of horse. Gurney demonstrated that the first 177 structural units (or nucleotides) of the DNA sequence matched the sequence of nucleotides for donkeys’ genetic material. The remaining 193 nucleotides match horse DNA. “It was easy to recognize that originally there must have been two separate DNA strands,” she says. The error might have occurred during the excavation work – perhaps DNA was transferred from one skeleton to another. Or possibly the error occurred inadvertently in the lab or afterwards during the data analysis at the computer.”
Although the scientists have not been able to confirm that a new breed of horse has been discovered, the result is still exciting, they say. If the donkey DNA really did come from the antique skeleton, this would demonstrate for the first time that the archetype of the domestic donkey typically found in Italy today was already being kept in ancient Pompeii. This lineage is descended from the Somali wild ass. In other European countries, by contrast, the donkeys kept are descended from the Nubian lineage. The ancient donkey DNA provides researchers with new insights into the history of donkey breeding.
The study involved not only Susan Gurney from Cambridge University, currently writing her PhD at the Institute of Animal Physiology headed by Prof. Wolf-Michael Weber, but also Dr. Peter Forster. Forster is a scientist at Münster’s Institute of Forensic Genetics, headed by Prof. Emeritus Bernd Brinkmann.
Susan M. R. Gurney (2010): Revisiting ancient mtDNA equid sequences from Pompeii. Journal of Cellular Biochemistry (Accepted manuscript online); DOI: 10.1002/jcb.22914
Dr. Christina Heimken | idw
Newly discovered bacteria-binding protein in the intestine
08.12.2016 | University of Gothenburg
The balancing act: An enzyme that links endocytosis to membrane recycling
07.12.2016 | National Centre for Biological Sciences
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
08.12.2016 | Materials Sciences
08.12.2016 | Materials Sciences
08.12.2016 | Physics and Astronomy