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  (Source: AP)
DNA comes from sequencing of Neanderthal toe-bone found in Siberia

Three years after an international team of experts led by researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany published a "draft" of the genome of Homo neanderthalensis (commonly known as the "Neanderthal"), the team has come back with a higher-quality "finished" map of the genome.

I. Getting to Know Our Neighbors, Distant Ancestors

Neanderthals are one of mankind's closest relatives.  Neanderthals and modern man (Homo sapiens) are though to have diverged from a common ancestor around 350,000 years ago.  That ancestor is thought to have evolved into humans in Africa, but into Neanderthals in Europe.  Another close relative, Denisovans, are thought to have diverged slightly earlier in Asia.

Nonetheless, humans and these relatives would eventually reunite and even have intimate sexual relationships, which led to some modern humans bearing pieces of Neanderthal/Denisovan DNA.

These "donations" from our close relatives are thought to have endowed people of European or Asian descent with hardier immune systems.

The DNA for the sequenced Neanderthal genome comes from a toe-bone found in the Denisova cave in southern Siberia.

Denisova cave
[Image Source: Current Biology/Science]

That cave is also home to preserved human and Denisovan remains; in fact the Denisovan remains are being used to carry out a similar sequencing project on that genome.

II. Contamination, Region Variance Leave Picture Only Mostly Complete

Svante Paabo, a geneticist who led the research, wrote in an email to the Associated Press, "The genome of a Neanderthal is now there in a form as accurate as that of any person walking the streets today."

Or it is for the Altal Neanderthals, at least.  Much like modern man, where people from different areas developed unique genetic makeups, Neanderthals are hypothesized to have subtle regional differences in their genomes.

As Ars Technica points out, it is misleading to suggest that the genome is a "complete" genome for the entirety of the Neanderthal population that once inhabited Europe, Asia, and the Middle East.  Rather, the Neanderthal genome represents a finished/complete picture of the Neanderthals in one region.

Family tree
Scientists think that the Altal branch of the "family tree" is complete with the finished sequencing. [Image Source: MPI]

Professor Paabo is preparing a paper on the work.  He enthuses, "We will gain insights into many aspects of the history of both Neanderthals and Denisovans, and refine our knowledge about the genetic changes that occurred in the genomes of modern humans after they parted ways with the ancestors of Neanderthals and Denisovan."

The finished genome is available here in "BAM" format, with chromosome file sizes ranging from 1.9-13 GB a piece, depending on the size, except for the small 'Y' chromosome, which is only 331 MB.

One other way that the genome is somewhat incomplete is contamination.  Analysis showed that approximately 1 percent of the DNA in the sample was contamination from the cave's later human residents.  Those gaps -- and the variations between Neanderthals in different regions -- will have to be filled in with future gene studies.

Source: MPI



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I see your genes are as big as mine...
By DNAgent on 3/21/2013 9:17:51 AM , Rating: 2
quote:
The finished genome is available here in "BAM" format, with genes ranging from 1.9-13 GB a piece, depending on the size, except for the small 'Y' chromosome, which is only 331 MB.


Should be "chromosome sizes ranging from 1.9-13 Gb a piece"




By DNAgent on 3/21/2013 9:20:25 AM , Rating: 2
Actually, that's wrong too...the file sizes range from 331 MB to 13 GB....chromosomes have more gigabases than that.


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