Sunday, October 27, 2013

Ancestor of Native Americans in Asia was 30% “Western Eurasian”

The complete genome has recently been sequenced from 4 year old Russian boy who died 24,000 years ago near Lake Baikal in a location called Mal’ta, the area in Asia believed to be the origin of the Native Americans based on Y DNA and mitochondrial chromosome similarities.  The map below, from Science News, shows the location.
malta boy map
This represents the oldest complete genome ever sequenced, except for the Neanderthal (38,000 years old) and Denisovan (41,000 years old).
This child’s genome shows that he is related closely to Native Americans, and, surprisingly, to western Asians/eastern Europeans, but not to eastern Asians, to whom Native Americans are closely related.  This implies that this child was a member of part of a “tribe” that had not yet merged or intermarried with the Eastern Asians (Japan, China, etc.) that then became the original Native Americans who migrated across the Beringian land bridge between about 15,000 and 20,000 years ago.
One of the most surprising results is that about 30% of this child’s genome is Eurasian, meaning from Europe and western Asia, including his Y haplogroup which was R and his mitochondrial haplogroup which was U, both today considered European.
This does not imply that R and U are Native American haplogroups or that they are found among Native American tribes before European admixture in the past several hundred years.  There is still absolutely no evidence in the Americas, in burials, for any haplogroups other than subgroups of Q and C for males and A, B, C, D, X and M (1 instance) for females.  However, that doesn’t mean that additional evidence won’t be found in the future.
While this is certainly new information, it’s not unprecedented.  Last year, in the journal Genetics, an article titled “Ancient Admixture in Human History” reported something similar, albeit gene flow in a different direction.  This paper indicated gene flow from the Lake Baikal area to Europe.  It certainly could have been bidirectional, and this new paper certainly suggests that it was.

Cont. Here:
http://dna-explained.com/2013/10/25/ancestor-of-native-americans-in-asia-was-30-western-eurasian/
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Friday, October 25, 2013

Technology, Word of Mouth Help Genealogy Hit the Mainstream

Jack Goins poses with a photo dated to have been taken in 1898 of his great-great grandparents found through genealogical research, May 23, 2012.

Mike Richman

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Sunday, October 20, 2013

Genealogy Sites on Pinterest


If you haven't checked out Pinterest lately for Genealogy sites, you really should do so now.

http://www.pinterest.com/geneabloggers/genealogy-tip-jar/

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Thursday, October 3, 2013

Family Tree DNA Rolls Out a New Look and Interface

With a hat tip to Rebekah Canada: 


FTDNA Family Finder Matches Get a New Look (Part 1)

FTDNA Family Finder Matches look a bit different today. It is a good thing. Here is how a typical Matches page looks when you open it. The first thing I noticed was that the Suggested Relationshipcolumn was gone. This makes me oh so happy. It has been the source of much confusion for a long time.
You will need to head to Family Tree DNA (FTDNA) and Login.



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Junk DNA: Not So Junky Anymore



Is Junk DNA Really Junky?

By 

The delicious, religious debate over what most of our genome is good for.

The silk dancers' interpretation of DNA loops.
Dancers' interpretation of DNA loops
Courtesy of Tom Whipps/Nature
In the 12 years since the human genome was sequenced, so many critters have had their DNA deciphered—oysters, bees, eels, camels, clawed frogs, elephant sharks—that it’s hard to suppress a yawn sometimes. But every so often, a genome cuts through the indifference and makes geneticists’ eyes goggle out. Take the humped bladderwort, a humble aquatic plant whoseDNA was sequenced this past May.
The humped bladderwort has yellow, snapdragon-like flowers, and it’s actually carnivorous, capable of trapping and eating not just insects but even tadpoles and tiny fish. But this combination of beauty and death isn’t what makes the bladderwort special. Most organisms have loads of junk DNA—less pejoratively, noncoding DNA—cluttering their cells. The bladderwort doesn’t: 97 percent of its DNA is classic, hardworking, protein-building DNA. And that lean, mean bladderwort DNA challenges some trendy notions about how all DNA works, including (if not especially) in human beings.
First, a primer on junk DNA, one of the most reviled terms in science. Anyone who took Bio 101 remembers (if only vaguely) that DNA gets turned into RNA, which in turn gets turned into proteins. The protein-producing stretches of DNA are called genes, and genes reside on much longer molecules called chromosomes.
A century ago, as biologists came to grips with the vast number of different proteins needed to build and maintain the body, they decided that genes must be packed very tightly together on chromosomes, since tight packing would be more efficient. They couldn’t have been more wrong. In humans, a typical species in this regard, less than 2 percent of our 3 billion letters of DNA actually builds proteins. Chromosomes were more like vast Saharan wastelands, broken up only sporadically by oases of genes.
So what does that extra 98 percent do? Here’s where things get contentious. Some of the excess—the pseudogenes, the transposons, the tedious stretches where Mother Nature held her fingers down on the keyboard (ACACACACACA ... )—does look like garbage. Heck, 8 percent of our genome is nothing but old, broken-down virus DNA, the genetic equivalent of a Pontiac Firebird on cinderblocks. The name junk DNAemerged in the early 1970s as a catchall term for this cruft.
Even at the time, though, some scientists objected to the term as too dismissive. Molecular biologists had already discovered bits of junk that, far from being irrelevant, actually managed genes: They turned genes on or off and regulated when and where genes were active. As more and more examples of this type of control emerged in the 1980s, the term junk DNA seemed less and less appropriate.

Cont. here:
http://www.slate.com/articles/health_and_science/human_genome/2013/10/junk_dna_debate_critics_of_the_encode_project_cite_humped_bladderwort.html





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