Niagara Gazette

Web Extra

January 30, 2014

Studies find Neanderthal genes in modern humans

WASHINGTON — Neanderthal genes lurk among us. Small traces of Neanderthal DNA have been confirmed in the areas of the genome that affect skin and hair of modern humans, according to two new studies that also give clues as to which Neanderthal traits may have been helpful - or harmful - to the survival of our species.

The studies, published online Wednesday in the journals Nature and Science, came to similar conclusions despite using vastly different methods of genomic analysis.

For East Asian and European populations, genes that provide the physical characteristics of skin and hair have a high incidence of Neanderthal DNA - possibly lending toughness and insulation to weather the cold as early man emerged from Africa, the studies conclude. Neanderthals were thought to have already been adapted to a chillier, more northern environment.

Perhaps most notably, Neanderthal DNA was not found in genes that influence testicles, according to the Nature study, hinting that when the Neanderthal ventured outside his own species for sex, the introduction of his DNA may have reduced male fertility in early humans.

"There's strong evidence that when the two met and mixed, they were at the edge of biological compatibility," said Nature study author and Harvard University geneticist David Reich. "The people who eventually survived and thrived had quite a bit of hurdles to overcome."

This is consistent with what is seen in nature: When two species mate that are sufficiently far away biologically, the resulting hybrids tend to have lowered fertility. Early humans and Neanderthals interbred about 40,000 to 80,000 years ago around the Middle East, during man's migration out of Africa.

And the last Neanderthals died off some 30,000 years ago.

Reich's team used an ancient genome his lab had sequenced last year - as high-quality as any modern DNA data set - from a 130,000-year-old female Neanderthal's toe bone found in a Siberian cave. They compared her data with 1,004 genomes of present-day humans, including those of sub-Saharan Africans. The Science study, led by University of Washington geneticist Joshua Akey, only used East Asian and European sequences, because indigenous Africans possess little or no traces of Neanderthal.

Because Neanderthals occupied Europe and Asia, African ancestors did not have the opportunity to interbreed with them. Reich and his colleagues used the African sequences as a sort of negative control; if parts of the ancient genome were found in East Asians and Europeans, but not in Africans, then those parts may have carried over from Neanderthals.

"Although it's true that each individual has only a small percentage of Neanderthal DNA, the small sequence that I carry might be different than the amount that you carry," Akey said. Non-African humans inherit about 1 to 3 percent of their genomes from Neanderthal ancestors, with East Asians tending to have a slightly larger proportion than Europeans.

In total, he found that all the sequence bits among his analysis population of 379 European and 286 East Asian subjects, in total, spanned about 20 percent of the Neanderthal genome. As opposed to Reich, Akey scanned the modern genomes without comparing against the ancient DNA, finding regions that were likely to be contributed by a certain era's ancestors. Only later did he compare those parts with the Neanderthal reference genome.

Geneticist Edward Rubin of the Lawrence Berkeley National Laboratory, who was not involved in the studies but has sequenced sections of the Neanderthal genome, found the results plausible and interesting.

 "I was stunned by the public interest in Neanderthals," he said. "Everybody wanted to know two things: whether we had sex with them, and we did, and what happened to them."

 Their DNA has confirmed interbreeding, but scientists don't know why these hominids failed to survive. Theories abound; some suggest a violent genocide at the hands of Homo sapiens, others say they fell short and died off.

 "They kind of disappear from the archeological record, and it's tempting to think that they were out-competed for resources," Reich said. "But we know they got incorporated into modern humans, and they live on in us today."

 

1
Text Only | Photo Reprints
Web Extra
  • NIA iPad pals art 1 120613 Has the iPad lost its swag?

    The company reported this week that sales of its sleek, pricey tablet were down 19 percent from last quarter and 9 percent year-over-year. CEO Tim Cook tried to reassure investors that Apple's new partnership with IBM to sell its devices to IBM's corporate customers will help make iPads ubiquitous in the workplace. "This isn't something that worries us," he said of the iPad sales decline. But the numbers are disappointing no matter how you spin them.

    July 25, 2014 1 Photo

  • Facebook continues moneymaking trend

    Facebook seems to have figured out - for now at least - the holy grail for all media right now: how to make money selling mobile ads.

    July 25, 2014

  • Police Brutality screen shot. Technology plays key part in battling police brutality (VIDEO)

    Allegations of police brutality are nothing new -- as long as there has been law enforcement, citizens have registered claims that some officers cross the line. But in the last few years, the claims of excessive force are being corroborated with new technology from cell phone cameras, police dash-cams and surveillance videos. 

    July 25, 2014 1 Photo

  • Arizona's prolonged lethal injection is fourth in U.S. this year

    Arizona's execution of double-murderer Joseph Wood marked the fourth time this year that a state failed to dispatch a convict efficiently, according to the Constitution Project, a bipartisan legal group.3

    July 25, 2014

  • Vader Darth Vader is polling higher than all potential 2016 presidential candidates

    On the other hand, with a net favorability of -8, Jar Jar is considerably more popular than the U.S. Congress, which currently enjoys a net favorability rating of -65.

    July 23, 2014 1 Photo

  • Screen Shot 2014-07-22 at 2.00.42 PM.png VIDEO: Train collides with semi truck carrying lighter fluid

    A truck driver from Washington is fortunate to be alive after driving his semi onto a set of tracks near Somerset, Ky., and being struck by a locomotive, which ignited his load of charcoal lighter fluid.

    July 22, 2014 1 Photo

  • An oncologist uses scorpion venom to locate cancer cells

    Olson, a pediatric oncologist and research scientist in Seattle, has developed a compound he calls Tumor Paint. When injected into a cancer patient, it seems to light up all the malignant cells so surgeons can easily locate and excise them.

    July 22, 2014

  • mama.jpg What we get wrong about millennials living at home

    If the media is to be believed, America is facing a major crisis. "Kids," some age 25, 26, or even 30 years old, are living out of their childhood bedrooms and basements at alarmingly high numbers. The hand-wringing overlooks one problem: It's all overblown.

    July 22, 2014 1 Photo

  • Lindley, Tom.jpg Expectations too high for a rehabbing Woods

    Tiger Woods finished near bottom last weekend at Royal Liverpool, drawing out his drought of major tournament wins. Despite the disappointing showing, Woods' return to form remains a matter of when, not if.

    July 22, 2014 1 Photo

  • 110720 Walmart.jpg Wal-Mart to cut prices more aggressively in back-to-school push

    Wal-Mart Stores plans to cut prices more aggressively during this year's back-to-school season and will add inventory to its online store as the chain battles retailers for student spending.

    July 22, 2014 1 Photo

Featured Ads
House Ads
AP Video
Raw: Massive Dust Storm Covers Phoenix 12-hour Cease-fire in Gaza Fighting Begins Raw: Bolivian Dancers Attempt to Break Record Raw: Israel, Palestine Supporters Rally in US Raw: Palestinians and Israeli Soldiers Clash Raw: Air Algerie Flight 5017 Wreckage Virginia Governor Tours Tornado Aftermath Judge Faces Heat Over Offer to Help Migrant Kids Kerry: No Deal Yet on 7-Day Gaza Truce Kangaroo Goes Missing in Oklahoma More M17 Bodies Return, Sanctions on Russia Grow Gaza Residents Mourn Dead Amid Airstrikes Raw: Deadly Tornado Hits Virginia Campground Ohio State Marching Band Chief Fired After Probe Raw: Big Rig Stuck in Illinois Swamp Cumberbatch Brings 'Penguins' to Comic-Con Raw: Air Algerie Crash Site in Mali Power to Be Restored After Wash. Wildfire Crashed Air Algerie Plane Found in Mali Israel Mulls Ceasefire Amid Gaza Offensive
Opinion
House Ads
Night & Day
Twitter News
Follow us on twitter
Hyperlocal Search
Premier Guide
Find a business

Walking Fingers
Maps, Menus, Store hours, Coupons, and more...
Premier Guide
Front page