Two recent papers describing the sequencing of Neanderthal nuclear DNA from fossil bone held promise for finally answering this question. However, the two studies came to very different conclusions regarding the ancestral role of Neanderthals.
Were Neanderthals direct ancestors of contemporary humans or an evolutionary side branch that eventually died out? This is one of the enduring questions in human evolution as scientists explore the relationship of fossil groups, such as Neanderthals, with people alive today. Two recent papers describing the sequencing of Neanderthal nuclear DNA from fossil bone held promise for finally answering this question [1, 2].
However, the two studies came to very different conclusions regarding the ancestral role of Neanderthals. Jeffrey D. Wall and Sung K. Kim from University of California San Francisco now reveal in PLoS Genetics what they found when they reanalyzed the data from the two original studies.
Wall and Kim’s reanalysis reveals inconsistencies between them and they believe that possible contamination with modern human DNA and/or a high rate of sequencing errors compromised the findings of one of the original Neanderthal DNA studies. The authors therefore recommend that we carefully evaluate published and future data before arriving at any firm conclusions about human evolution.
References:
1. Noonan JP, Coop G, Kudaravalli S, Smith D, Krause J, et al. (2006) Sequencing and analysis of Neanderthal genomic DNA. Science 314: 1113-1118.
2. Green RE, Krause J, Ptak SE, Briggs AW, Ronan MT, et al. (2006) Analysis of one million base pairs of Neanderthal DNA. Nature 16: 330-336.
Citation: Wall JD, Kim SK (2007) Inconsistencies in Neanderthal genomic DNA sequences. PLoS Genet 3(10): e175. doi:10.1371/journal.pgen.0030175
Source: Public Library of Science
Related stories:
Neanderthal genome unlocks secrets of human evolution
The veil of mystery surrounding our extinct hominid cousins, the Neanderthals, has been at least partially lifted to reveal surprising results. Scientists with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and the Joint Genome Institute (JGI) have sequenced genomic DNA from fossilized Neanderthal bones.
Oldest Fossil Protein Sequenced
Protein sequence from Neanderthal extracted and sequenced
An international team, led by researchers at the Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, in Leipzig, Germany, have extracted and sequenced protein from a Neanderthal from Shanidar Cave, Iraq dating to approximately 75,000 years old. It is rare to recover protein of this age, and remarkable to be able to determine the constituent amino acid sequence. This is the oldest fossil protein ever sequenced. Protein sequences may be used in a similar way to DNA, to provide information on the genetic relationships between extinct and living species. As ancient DNA rarely survives, this new method opens up the possibility of determining these relationships in much older fossils which no longer contain DNA (PNAS Online Early Edition, March 8, 2005).
Studies spot numerous undiscovered gene alterations in pancreatic and brain cancers
HHMI investigators have detected a multitude of broken, missing, and overactive genes in pancreatic and brain tumors, in the most detailed genetic survey yet of any human tumor. Some of these genetic changes were previously unknown and could provide new leads for improved diagnosis and therapy for these devastating cancers.
Trichoplax genome sequenced -- 'rosetta stone' for understanding evolution
(PhysOrg.com) -- Yale molecular and evolutionary biologists in collaboration with Department of Energy scientists produced the full genome sequence of
Trichoplax, one of nature's most primitive multicellular organisms, providing a new insight into the evolution of all higher animals.
Study: DNA barcoding in danger of 'ringing up' wrong species
DNA barcoding is a movement to catalog all life on earth by a simple standardized genetic tag, similar to stores labeling products with unique barcodes. The effort promises foolproof food inspection, improved border security, and better defenses against disease-causing insects, among many other applications.
Gene that causes childhood cancer neuroblastoma is found
Scientists have discovered gene mutations that are the main cause of the inherited version of the childhood cancer neuroblastoma. In addition, the researchers found that the same mutations play a significant role in high-risk forms of non-inherited neuroblastoma, the more common form of the disease.
Scientists nail childhood nerve cancer gene
Researchers have identified the hereditary gene mutations behind a deadly form of childhood cancer, opening the way to genetic tests in high-risk families, according to study released Sunday.
Genome of simplest animal reveals ancient lineage, confounding array of complex capabilities
As Aesop said, appearances are deceiving—even in life's tiniest critters. From first detection in the 1880s, clinging to the sides of an aquarium, to its recent characterization by the U.S. Department of Energy Joint Genome Institute (DOE JGI), a simple and primitive animal, Trichoplax adhaerens, appears to harbor a far more complex suite of capabilities than meets the eye. The findings, reported in the August 21 online edition of the journal
Nature, establish a group of organisms as a branching point of animal evolution and identify sets of genes, or a "parts list," employed by organisms that have evolved along particular branches.