DNA Testing Of Deep Ancestry
Randall Burns writes: "
Oxford Ancestors, founded by world-famous University of Oxford scientist
Bryan Sykes has announced the public availability of an inexpensive($US 180) service that will trace matrilineal ancestry using DNA tests. Applications include forensics, genealogy and research of history. Coverage includes a recent BBC story. The currently available test can trace matrilineal ancestry back to one of seven women who lived 150,000 years ago to which 99% of all people of European descent can trace their ancestry."
99% of people come from one of these seven women? Man, they must have been huge sluts! :)
Seriously, I don't see the point of this. When people want to trace their ancestry, they're mostly concerned with who their great great grandparents were and who their relatives were that lived during the Civil war, not 150,000 years ago. Yeah, it's cool, but nothing I'd pay $180 for.
Can this technology help us finally figure out what species Janet Reno is?
SILLY SLASHDOTTER, WHY YOU NO PAY ATTENTION!!! OOG BE FIRST SLASHDOTTER IN RECORDED HISTORY, EVEN BEFORE TACO CREATE SLASHDOT!!! EXCEPT OOG NO LIVE IN GREAT RIFT VALLEY, THAT JUST BASTARD COUSIN OF MINE (RIFT VALLEY HAVE SHITTY INTERNET ACCESS, OOG DEMAND BROADBAND)!!! ALTHOUGH SHITTY GENE TRACING PROGRAMS NO MENTION OOG, OOG BE REAL ANCESTOR!!! OOG BREAK HEAD WITH OPEN SOURCE CD AND POST SLASHDOT SINCE MAN FIRST EVOLVE!!!
OOG WONDER HOW DARE YOU OVERLOOK YOUR HERITAGE!!! WHY YOU BE UNGRATEFUL BASTARD!!! IF NOT FOR OOG YOU NO HAVE SLASHDOT ACCOUNT WITH +1 BONUS!!! OOG DISSAPPOINTED IN YOU!!! AS OF TODAY OOG CUT YOU OUT OF INHERITANCE OF OOG FAMILY FORTUNE!!! OOG SUGGEST YOU SHOW MORE RESPECT TO CAVEMAN ANCESTOR!!! PERHAPS OOG ALSO SHOW YOU DISCIPLINE BY BREAK HEAD!!!
OOG THE OPEN SOURCE CAVEMAN!!! OOG BREAK HEAD WITH OPEN SOURCE CD!!!
Gee, SEVEN women? Adam had quite a harem!!!
--
[luke skywalker]
NOOOOOOOOOOOOooooooooo! ! ! ! !
;)
___
(Scene opens with armored mercenary on horseback approaching a stone castle retrofitted out of the decaying hulk of the abandoned steel husk of an office building. Camera pans, giving audience a breathtaking view of the barren, wrecked skyline of a post-apocalyptic American metropolis.)
Guard (steel spear glinting as he shouts): "Halt! Who goes there? Know ye that this place be the realm of the descendents of Bertha the Bountiful. If thou be a son of Agnes the Prolific, begone from here, lest we slay thee!"
Mercenary: "Good soldier! Stay thine blade, for I, too am of the Tribe of Bertha!"
Guard (in stupid, low grunting Superbowl-commercial voice): "Whazzuuuuuuuuuuuuuuup!"
Mercenary pulls a flintlock pistol from his belt, cocks the hammer, and fires at Guard, killing him instantly. Audience cheers.
Guard (lacking the decency to just DIE): "Lo! I am sped! Dead am I! I am made as dust by the treacherous asp! Gone am I from this mortal coil! I am---"
Mercenary: "Why won't you DIE??!"
(Mercenary dismounts, then proceeds to kick Guard till he falls dead, and more importantly, silent. Audience cheers.)
Mercenary: Never underestimate the 1% descended from Jane Doe the Probably-Just-a-Rounding-Error-In-Our-Calculations !
Mercenary proceeds to singlehandedly storm the castle, raping and pillaging, stealing treasure, weapons, and office supplies.
Stay up hacking each weekend. Sleep is for the week.
first of all the bbc link shoud point to: http://news.bbc.co.uk/hi/english/sci/tech/newsid_7 19000/719376.stm According to BBC story all 7 women decended from one of three clans that still exist in Africa today. I assume the other 1% of homo sapians would have decended from the other two clans. Wouldn't it be cool if we could trace combine this with historical and archeological records as well as some new genttic research to create a family tree of the entire human race. We could set it up a server with a CVS like service that people could login to and submit their familt trees. Historians an scientists could be responsible for putting it all together and tracking our ancient ancestors. The information could be put on the internet giving people that are still alive a serial number to protect their privacy. Maybe Slashdot could even set uo a page when you put in you serial number and it tells you how close of a releative you are to linus, Gates, John Katz, etc
--- Justin Dearing http://www.justaprogrammer.net/ We're just programmers.
However, it won't be that useful to geneaologists in the long run. The reason: a sad fact of European society (and most others, actually, dating back for most of recorded history): the family name and identity was generally handed down in a patrilineal manner, while mitochondria can only trace matrilineal ancestry. I guess it's sorta understandable, though; back when those rules were made the people didn't know about mitochondrial DNA (or, for that matter, any other kind of DNA).
Furthermore, mitochondrial DNA tracing is far less specific, since barring mutations mitochondrial DNA is identical from generation to generation. In other words, you're not going to get accurate family lineage tracing this way. You can get into the general ballpark (tracing back to one of seven women 150,000 years ago, for example) but you can't be very exact.
I guess it would have important symbolic value, however, particularly among warring nations. It proves that, in a way, we're all brothers (and sisters too, of course). Now if only we could get a few certain groups in the world, who shall remain nameless, to get that through their skulls...
The Oxford Ancestors Matriline service relies on mitochondrial DNA which doesn't mutate often enough to provide the fine matrilineal distinctions that would be required for different matrilines that have a common matrilineal ancestress as recently as the Pictish clans probably do. However, it is interesting that the legend of the Pictish clans sets their number at 7 -- which is the same number of matrilines Sykes says constitutes 99% of the indigenous Europeans.
Seastead this.
Mixed population bacterial genetics may be a far better anology than eukayotic (nuclear) genetics for explaining the distribution and prevalence of mitochondrial populations
First, some much simplified background (I have a degree in molecular biology): Mitochondria are self-reproducing organelles (= cell 'organs') that many people believe were once independent organisms that entered into a symbiotic relationship with a host cell, and eventually became utterly dependent on the cell. They now function as the primary site for the production of ATP, the main cellular fuel. There may be hundreds or thousands in a single cell
Mitochondria reproduce (to some degree) independently of the cell, and contain their own DNA. The DNA for everything else is in the nucleus (the cell's brain) but the mitochondria 'live' and reproduce in cytoplasm (cell body). When we breed, the nuclear DNA does the whole dance of meiosis/mitosis we learned in school, but the mitochondria fission like bacteria. Most (if not all) of the mitochondria is from the mother because a) the egg has thousands of times as much cytoplasm as the sperm; and b) after first contact with the egg, the sperm's mitochondria go into hyperdrive ("the acrosome reaction") and burn themselves out.
Now for the Original Contributions
1. In the billions of years of symbiosis since the development of eukaryotes, many genes that are useful or essential to the mitochondria have 'migrated' into the nucleus.
2. Though the mitchondrial 'support' genes are fairly cosistent from person to person, they aren't identical in everyone. Those genes only got to the nucleus by accident (mutation, adaptation by mitochondria to the available cell resources, etc) and therefore not all strains may be able to live in all people, or certain strains may enjoy a competititve advantage in a given person
3. Some individuals are known to have multiple strains of mitochondria, due to the various flukes and accidents of biological history. I know of no study that states that *most* humans have only one strain, and doubt its the case. It's actually a good idea to have multiple strains, since anything that kills (or impedes the reproduction of) a solo strain would kill (or prevent the reproduction of) its host. Multistrain individuals should be slightly hardier.
4. Mitochondria became part of the cell when we were single celled organisms. The mitochondrial DNA variation we measure is presumed to be 'nonessential' because mitochondria have very little DNA, and most of it was largely fixed long ago. We presume we're sorting mitochondria by 'eye color', but we may not be.
4) Mitochondria must adapt to their host as the host changes. A cow's mitochondria is much less similar to ours than you'd expect, considering that cows and men didn't diverge very long ago on a mitchondrial timescale.
5) Suppose a type mitochondria in a remote tribe requires the (nucleus) gene PII'ase. This is fine if the tribe all carries the (nuclear) gene for PII'ase. However, this mitochondrial line may die out when interbred because outside populations may not carry the gene PII'ase.
6) I can think of a dozen other mechanisms, but let's not go overboard.
Conclusion:
Mitochondria are subject to many of the evolutionary and selection pressures as independent bacteria, symbiotes, etc. the finding that there are seven major strains of mitochondria in modern man simply suggests that seven mitochondrial strains are widespread and well-adapted to the core genome of humans
It doesn't mean there were only seven 'original women'
It may mean that there were only seven (mitochondrially) *undemanding* women [ducks!] and the truth may be far more complicated. (lesser strains may coexist with the support of the major strains, etc.) and probably are.
If you can go to bed, knowing you did a valuable thing today, you're very lucky. If you can't... it's not bedtime