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 (Berkeley Lab) and the Joint Genome Institute (JGI) have sequenced genomic DNA from fossilized Neanderthal bones. Their results show that the genomes of modern humans and Neanderthals are at least 99.5-percent identical, but despite this genetic similarity, and that the two species cohabitated the same geographic region for thousands of years, there is no evidence of any significant crossbreeding between the two. Based on these early results, Homo sapiens and Homo neanderthalensis last shared a common ancestor approximately 700,000 years ago
In a paper published in the November 17, 2006 issue of the journal Science, a team of researchers led by Edward Rubin, director of both JGI and Berkeley Lab's Genomics Division, reports the development of a "Neanderthal metagenomic library," which they used to characterize more than 65,000 DNA base pairs of Neanderthal origin. Their results not only provide new information about Neanderthals, but also point the way to a new strategy for studying aspects of Neanderthal biology that would never be evident from archaeological artifacts and fossils.
In addition, the technology described in the paper also marks an important advance in the field of metagenomics, which is increasingly being used to sequence the complex mixtures of microbes found in the environment. Metagenomics techniques are considered crucial for tapping the potential of Earth's more exotic microbe-containing environments to find bio-based solutions to problems of renewable energy production, environmental clean-up, and carbon sequestration, as well as breakthroughs in critical areas such as pharmaceuticals and agriculture.