Thursday, March 08, 2012 6:29:36 AM
Humans and Gorillas Closer Than Thought, Genome Sequence Says
Photographer: Mark Bridger/Getty Images
By Elizabeth Lopatto - Mar 7, 2012 12:00 PM CT
Gorillas have been portrayed as militaristic bullies in the Planet of the Apes movies and as “highly social gentle giants” by researcher Dian Fossey.
Now scientists say they’re closer genetically to humans than they once thought.
Sequencing the genome of a female western lowland gorilla named Kamilah determined that most gorilla DNA is similar or identical to those of humans, despite the 10 million-year gap since the two species split off, according to a report today in the journal Nature.
In 30 percent of the genome, the study determined that gorillas are closer to humans and chimpanzees than the latter two are to each other. It’s a finding that may help scientists track changes in how the species have responded over time to shared genetic characteristics, including diseases, the researchers said.
“If we can understand why they’re harmful in humans but not in gorillas, that would have useful medical implications,” said Chris Tyler-Smith [ http://www.sanger.ac.uk/research/faculty/ctylersmith/ ], head of the human evolution team at Wellcome Trust Sanger Institute in Hinxton, England.
Gorillas are the last of the great ape genus to have their genome sequenced, the investigators said. The group saw changes in genes involved in sperm production and in the formation of keratin proteins in the skin.
Additionally, gene variants that in humans cause genetic disease don’t seem to affect gorillas similarly, said Tyler- Smith, one of the study’s authors.
Dementia Gene
One of the genes, PGRN, has a mutation [ http://neurology.jwatch.org/cgi/content/full/2006/926/1 ] that causes frontotemporal dementia in humans. Another, called TCAP, a human variant that causes hypertrophic cardiomyopathy, a condition where the heart muscle thickens, makes it hard for blood to leave the heart.
Both humans and gorillas have accelerated evolution in genes associated with hearing, suggesting that the changes aren’t related to speech, Tyler-Smith said.
Because gorillas live in groups with one male and many females, there isn’t a lot of sperm competition, so many genes involved in sperm formation are either inactive or decreased in numbers in gorillas. And a gene called EVTL, which contributes to keratin formation in the skin, is evolving very rapidly in gorillas, who walk using knuckles that are padded with keratin.
Humans overall are still closer to chimpanzees in 70 percent of the genome, said study author Aylwyn Scally, a postdoctoral fellow at the Wellcome Trust Sanger Institute.
Ape Separation
“When we look at human evolution, there’s an emphasis on chimpanzees because they’re closer, and other great apes get overlooked,” said Tara Stoinski, chief scientist of the Dian Fossey Gorilla Fund [ http://www.gorillafund.org/ ] International, based in Atlanta.
“This lets us understand the relationships further back in our ancestry,” Stoinski, who wasn’t involved in the research, said in a telephone interview.
Human beings separated from chimpanzees 6 million years ago, and from gorillas about 10 million years ago, according to the report in Nature.
About half a million years ago, gorillas split into two species, the eastern gorilla, featured in Dian Fossey’s book, “Gorillas in the Mist,” and the western gorilla, whose genome sequence was published today.
Fossey was inspired by Jane Goodall’s work with chimpanzees and established a research center called Karisoke, in Rwanda. She knuckle-walked with the gorillas, habituating them to her presence so she could study them. Later, she tried to protect them from poachers after Digit, a gorilla she was especially close to, was killed in 1977. In 1983, she published “Gorillas in the Mist,” a description of her time with the gorillas that underscored conservation. Fossey was murdered in 1985, and buried next to Digit.
Koko the Gorilla
Koko the gorilla [ http://www.koko.org/index.php ], who “speaks” using sign language, is a western lowland gorilla; her relationship with a pet cat was featured in the book “Koko’s Kitten.” Francine Patterson, a scientist who taught a modified form of sign language to the gorilla named Koko, portrayed the relationship between the gorilla and a housecat in the book.
Since the latest species split, eastern and western gorillas appear to have continued exchanging genetic information through sexual liaisons, researcher has suggested.
In the future, the scientists plan to look at the eastern gorillas, which have been studied more extensively in the field than western gorillas, Tyler-Smith said. Both species live in Africa, separated by the Congo River. The western gorillas are critically endangered, threatened by Ebola and being eaten by humans as meat; eastern gorillas are endangered, Stoinski said.
The human genome sequence was declared complete [ http://www.sciencemag.org/site/feature/data/dna/ ] in 2003, the chimpanzee [ http://www.genome.gov/15515096 ] in 2005, and the orangutan [ http://www.nature.com/nature/journal/v469/n7331/full/nature09687.html ] in 2011.
To contact the reporter on this story: Elizabeth Lopatto in New York at elopatto@bloomberg.net
To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net
©2012 BLOOMBERG L.P.
http://www.bloomberg.com/news/2012-03-07/humans-and-gorillas-closer-than-thought-study-of-great-ape-genome-finds.html [with comments]
===
Gorilla genome analysis reveals new human links
The first full genome analysis has revealed that 15% of gorillas' genetic code is closer between humans and gorillas than it is between humans and chimpanzees.
Photograph: Luanne Cadd
First full sequence of gorilla genome shows 96% share with humans, with close parallels in sensory perception and hearing
Alok Jha, science correspondent
guardian.co.uk, Wednesday 7 March 2012 13.00 EST
Humans and gorillas last shared a common ancestor 10 million years ago, according to an analysis of the first full sequence of the gorilla genome. The gorilla is the last of the living great apes – humans, chimpanzees, gorillas and orangutans – to have its complete genetic code catalogued.
Scientists, led by researchers from the Wellcome Trust Sanger Institute near Cambridge and Baylor College of Medicine in Houston, also found that 15% of the gorilla's genetic code is closer between humans and gorillas than it is between humans and chimpanzees, our closest animal relative. The genomes of all three species are, in any case, highly similar: humans and chimpanzees share more than 98% of their genes, while humans and gorillas share more than 96%.
The genetic sequence was taken from a female western lowland gorilla (Gorilla gorilla gorilla) named Kamilah and published in Nature.
An initial analysis also showed similarities in genes involved in sensory perception and hearing, and brain development showed accelerated evolution in all three species. Genes associated with proteins that harden up skin were also particularly active in gorillas – which goes some way to explaining the large, tough knuckle pads on gorillas' hands.
"Gorillas are an interesting animal in their own right but the main reason they are of particular interest is because of their evolutionary closeness to us," said Aylwyn Scally, an author of the research from the Wellcome Trust Sanger Institute. "They're our second-closest evolutionary cousins after chimpanzees and knowing the content of the gorilla genome enables us to say quite a lot about an important period in human evolution when we were diverging from chimpanzees."
Comparing the sequences of humans, chimpanzees and gorillas has enabled scientists to put a more accurate clock on when the three species split from their last common ancestors. It was traditionally thought that the emergence of new species (known as "speciation") happens at a relatively localised point in time but emerging evidence suggests that this is not necessarily the case, that species split over an extended period. Studying the gorilla genome suggests that the divergence of gorillas from the common ancestor of humans and chimpanzees happened around 10 million years ago. Humans and chimpanzees last shared a common ancestor around 6 million years ago. Eastern and western gorillas split some time in the last million years.
One curious find was the evolution of genes associated with hearing, which seem very similar between humans and gorillas. "Scientists had suggested that the rapid evolution of human hearing genes was linked to the evolution of language," said Chris Tyler-Smith, senior author from the Wellcome Trust Sanger Institute. "Our results cast doubt on this, as hearing genes have evolved in gorillas at a similar rate to those in humans."
Scally adds that it could well be that there has been a parallel acceleration in these genes for two entirely different reasons – that human hearing has developed because of speech and gorilla hearing has developed to serve an entirely different, but as-yet-unknown, purpose.
The researchers said that studying the gorilla genome would shed light on a time when apes were fighting for survival across the world.
"There's an interesting background story of great ape evolution," says Scally. "The common ancestor of all four great apes was sometime back in 15 to 20 million years ago. At that time, it seems to have been a nice time to have been an ape – it was a golden age – a lot of the world was just right for the kind of environment for apes to live in. Since that time, the story has been of fragmentation and extinction – most of the great ape species that have existed have gone. Today, all the non-human apes are really endangered populations, they're living in forest refuges and population numbers are quite low. Humans look like an exception to that – we're all over the world now and live in places where you could never have had a primate beforehand."
Today, gorillas are classified as critically endangered and populations have plummeted to below 100,000 individuals in recent decades due to poaching and disease. They are restricted to equatorial forests in countries including Cameroon, Central African Republic, Gabon, Nigeria, Republic of Congo and Angola.
"As well as teaching us about human evolution, the study of great apes connects us to a time when our existence was more tenuous," say the researchers in Nature. "And in doing so, highlights the importance of protecting and conserving these remarkable species."
© 2012 Guardian News and Media Limited
http://www.guardian.co.uk/science/2012/mar/07/gorilla-genome-analysis-new-human-link
===
Gorillas More Related to People Than Thought, Genome Says
Surprising differences include gene that aids knuckle walking
March 7, 2012
http://news.nationalgeographic.com/news/2012/03/120306-gorilla-genome-apes-humans-evolution-science/ [with comment]
===
Gorilla genome sheds new light on human evolution
By Kate Kelland
LONDON | Wed Mar 7, 2012 3:25pm EST
LONDON (Reuters) - Scientists have sequenced the genome of the gorilla, the last great ape to have its genes decoded, and say it gives new insights into differences between the apes and humans -- including their ability to produce competitive sperm.
While confirming that our closest relative is the chimpanzee, the research also shows that around 15 percent of the human gene map resembles the gorilla more closely than it does the chimpanzee genome.
Chris Tyler-Smith, who worked with a team of scientists who presented their findings in a telephone briefing, said that while many human genes are similar to the gorilla versions, it is the ones that differ that are often most intriguing.
One difference that stuck out was in the genes involved in sperm production, he said.
"Gorillas live in groups with one male and lots of females, so there's not much opportunity for sperm competition," he explained. "It was interesting for us to see that some genes involved in sperm formation...had either become inactive in gorillas or had decreased in copy number."
The study was published in the journal Nature on Wednesday.
Gorillas survive in just a few isolated and endangered populations in the equatorial forests of central Africa. There are two distinct species, one known as the eastern lowland and mountain gorillas, and the other known as western lowland and cross river gorillas.
The team used DNA from a western lowland gorilla, named Kamilah, to assemble a gorilla genome sequence and then compared it with the gene maps of the other great apes.
They also sampled DNA sequences from other gorillas so they could explore genetic differences between gorilla species.
"The gorilla genome is important because it tells us about that crucial time when we were diverging from our closest evolutionary cousins," said Aylwyn Scally of Britain's Wellcome Trust Sanger Institute, who led the research team.
The human genome project was completed in 2003, while the chimpanzee gene map was published in 2005 and the orangutan genome was completed in 2011.
"Comparisons between these can help us explore the origins of humans when we separated from the great ape species in Africa between 6 and 10 million years ago," said Richard Durbin, who also worked on the study at the Sanger Institute.
The team searched more than 11,000 genes in human, chimpanzee and gorilla for genetic changes important in evolution. They found as expected that humans and chimpanzees are genetically closest to each other over most of the genome, but they found many places where this is not the case.
In all three species, genes relating to sensory perception, hearing and brain development showed accelerated evolution, the researchers said, particularly in humans and gorillas.
The team found that divergence of gorillas from humans and chimpanzees happened around ten million years ago, but the split between eastern and western gorillas was much more recent and more gradual. They compared this split to the one between chimpanzees and bonobos, or modern humans and Neanderthals.
SOURCE: Nature, March 8, 2012 [ http://www.nature.com/nature/journal/v483/n7388/full/nature10842.html ( http://bit.ly/wMPeyt )].
Copyright 2012 Reuters
http://www.reuters.com/article/2012/03/07/us-gorilla-genome-sheds-new-light-human-idUSTRE8261VA20120307 [with comment]
===
Gorilla genome could hold key to the human condition
Video [embedded]
Researchers in Cambridge can now compare human DNA with that of all the other apes
By Pallab Ghosh
Science correspondent, BBC News
7 March 2012 Last updated at 13:03 ET
Researchers in Cambridge have deciphered the genetic code of the gorilla - the last of the Great Ape genuses to be sequenced.
Writing in the journal Nature, the scientists say that researchers can now begin to examine the similarities and differences between the apes.
Genome sequences of humans, chimpanzees and orangutans are already published.
The team hopes their work will help to uncover genetic mutations that led to language, culture and science.
"I'd like to think that in the next 20 or 30 years we will get a deeper understanding of what happened genetically in our evolutionary history, and of how those genes affect the brain and other properties that make us modern humans," said Richard Durbin of the Wellcome Trust Sanger Institute, who led the study.
Initial comparisons confirm that chimpanzees are our closest relatives, sharing 99% of our DNA. Gorillas come a close second with 98%, and orangutans third with a 97% share.
That reflects the evolutionary history of apes. Genome comparison indicates that the human lineage separated from orangutans 14 million years ago, gorillas 10 million years ago, and chimps 6 million years ago.
That order of events is not a surprise, but the dates are earlier than many scientists had thought.
Although on average we are closest to chimps, many of our individual genes are more like those of gorillas.
Among them is a gene that enables us and gorillas to hear better than other apes.
Until now, some scientists had thought that the development of hearing was what enabled us to develop language - but as a result of this research, we now know this theory is wrong.
Fifteen percent of the human genome is closer to the gorilla than the chimpanzee, and 15% of the chimpanzee genome is closer to the gorilla than to humans.
One genetic difference that will be of interest to medical researchers is a mutation that results in dementia in humans, but seems to leave gorillas completely unaffected.
Rapid emergence
The genome unravelled in the research came from a female western lowland gorilla (Gorilla gorilla gorilla) called Kamilah.
The study shows that humans are more similar to gorillas than previously thought
Researchers searched through more than 11,000 genes in her genome, as well as in the published versions of the human, chimp and orangutan genetic codes, for changes important in evolution.
"Our most significant findings reveal not only differences between the species, reflecting millions of years of evolutionary divergence, but also similarities in parallel changes over time since their common ancestor," said Chris Tyler-Smith, who works with Dr Durbin.
Comparative studies will also shed more light on the evolution of all the Great Apes; but the key question is whether the bounty of genetic information contains clues to the moment when the first genes emerged that made humans capable of abstract thought.
"This is the question we are all fascinated by," Dr Durbin told BBC News.
It is unlikely that a single development led to our species' advance towards modernity, or that all developments along that path were genetic.
Anatomically modern humans (Homo sapiens) emerged around 200,000 years ago, but it was not until about 50,000 years ago that our bigger brains began to make a difference.
Until then, humanity was one among small number of apes in Africa, probably living not very differently from gorillas.
Gorilla and human skulls: how did the human brain evolve to be capable of abstract thought?
So, something happened very rapidly around that time that led to the emergence of abstract thought, allowing humans to invent advanced tools and use them to shape the environment.
"There will have been genetic factors," said Dr Durbin, "but also cultural and historic factors."
The one Great Ape not to be sequenced so far is the bonobo, a close relative of the chimp. That project is underway, and scientists expect its genome and that of the chimp to be very similar.
The availability of the genomes of all the Great Apes will help scientists answer what happened over the past 200,000 years to enable our species become what we are now.
*
Related Stories
How man 'lost his penile spines' 09 MARCH 2011, SCIENCE & ENVIRONMENT
http://www.bbc.co.uk/news/science-environment-12689692
Orangutan genome 'evolved slowly' 27 JANUARY 2011, SCIENCE & ENVIRONMENT
http://www.bbc.co.uk/news/science-environment-12286281
Most human gene variations mapped 27 OCTOBER 2010, SCIENCE & ENVIRONMENT
http://www.bbc.co.uk/news/science-environment-11632164
Apes 'extinct in a generation' 31 AUGUST 2005, SCI/TECH
http://www.bbc.co.uk/2/hi/science/nature/4202734.stm
Related Internet links
Nature
http://www.nature.com/
Sanger Institute
http://www.sanger.ac.uk/
*
BBC © 2012
http://www.bbc.co.uk/news/science-environment-17239059
===
Gorilla joins the genome club
Sequencing of gorilla genome adds to understanding of our evolutionary path
07 March 2012
http://www.nature.com/news/gorilla-joins-the-genome-club-1.10185
*
Insights into hominid evolution from the gorilla genome sequence
Published online 07 March 2012
http://www.nature.com/nature/journal/v483/n7388/full/nature10842.html
Photographer: Mark Bridger/Getty Images
By Elizabeth Lopatto - Mar 7, 2012 12:00 PM CT
Gorillas have been portrayed as militaristic bullies in the Planet of the Apes movies and as “highly social gentle giants” by researcher Dian Fossey.
Now scientists say they’re closer genetically to humans than they once thought.
Sequencing the genome of a female western lowland gorilla named Kamilah determined that most gorilla DNA is similar or identical to those of humans, despite the 10 million-year gap since the two species split off, according to a report today in the journal Nature.
In 30 percent of the genome, the study determined that gorillas are closer to humans and chimpanzees than the latter two are to each other. It’s a finding that may help scientists track changes in how the species have responded over time to shared genetic characteristics, including diseases, the researchers said.
“If we can understand why they’re harmful in humans but not in gorillas, that would have useful medical implications,” said Chris Tyler-Smith [ http://www.sanger.ac.uk/research/faculty/ctylersmith/ ], head of the human evolution team at Wellcome Trust Sanger Institute in Hinxton, England.
Gorillas are the last of the great ape genus to have their genome sequenced, the investigators said. The group saw changes in genes involved in sperm production and in the formation of keratin proteins in the skin.
Additionally, gene variants that in humans cause genetic disease don’t seem to affect gorillas similarly, said Tyler- Smith, one of the study’s authors.
Dementia Gene
One of the genes, PGRN, has a mutation [ http://neurology.jwatch.org/cgi/content/full/2006/926/1 ] that causes frontotemporal dementia in humans. Another, called TCAP, a human variant that causes hypertrophic cardiomyopathy, a condition where the heart muscle thickens, makes it hard for blood to leave the heart.
Both humans and gorillas have accelerated evolution in genes associated with hearing, suggesting that the changes aren’t related to speech, Tyler-Smith said.
Because gorillas live in groups with one male and many females, there isn’t a lot of sperm competition, so many genes involved in sperm formation are either inactive or decreased in numbers in gorillas. And a gene called EVTL, which contributes to keratin formation in the skin, is evolving very rapidly in gorillas, who walk using knuckles that are padded with keratin.
Humans overall are still closer to chimpanzees in 70 percent of the genome, said study author Aylwyn Scally, a postdoctoral fellow at the Wellcome Trust Sanger Institute.
Ape Separation
“When we look at human evolution, there’s an emphasis on chimpanzees because they’re closer, and other great apes get overlooked,” said Tara Stoinski, chief scientist of the Dian Fossey Gorilla Fund [ http://www.gorillafund.org/ ] International, based in Atlanta.
“This lets us understand the relationships further back in our ancestry,” Stoinski, who wasn’t involved in the research, said in a telephone interview.
Human beings separated from chimpanzees 6 million years ago, and from gorillas about 10 million years ago, according to the report in Nature.
About half a million years ago, gorillas split into two species, the eastern gorilla, featured in Dian Fossey’s book, “Gorillas in the Mist,” and the western gorilla, whose genome sequence was published today.
Fossey was inspired by Jane Goodall’s work with chimpanzees and established a research center called Karisoke, in Rwanda. She knuckle-walked with the gorillas, habituating them to her presence so she could study them. Later, she tried to protect them from poachers after Digit, a gorilla she was especially close to, was killed in 1977. In 1983, she published “Gorillas in the Mist,” a description of her time with the gorillas that underscored conservation. Fossey was murdered in 1985, and buried next to Digit.
Koko the Gorilla
Koko the gorilla [ http://www.koko.org/index.php ], who “speaks” using sign language, is a western lowland gorilla; her relationship with a pet cat was featured in the book “Koko’s Kitten.” Francine Patterson, a scientist who taught a modified form of sign language to the gorilla named Koko, portrayed the relationship between the gorilla and a housecat in the book.
Since the latest species split, eastern and western gorillas appear to have continued exchanging genetic information through sexual liaisons, researcher has suggested.
In the future, the scientists plan to look at the eastern gorillas, which have been studied more extensively in the field than western gorillas, Tyler-Smith said. Both species live in Africa, separated by the Congo River. The western gorillas are critically endangered, threatened by Ebola and being eaten by humans as meat; eastern gorillas are endangered, Stoinski said.
The human genome sequence was declared complete [ http://www.sciencemag.org/site/feature/data/dna/ ] in 2003, the chimpanzee [ http://www.genome.gov/15515096 ] in 2005, and the orangutan [ http://www.nature.com/nature/journal/v469/n7331/full/nature09687.html ] in 2011.
To contact the reporter on this story: Elizabeth Lopatto in New York at elopatto@bloomberg.net
To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net
©2012 BLOOMBERG L.P.
http://www.bloomberg.com/news/2012-03-07/humans-and-gorillas-closer-than-thought-study-of-great-ape-genome-finds.html [with comments]
===
Gorilla genome analysis reveals new human links
The first full genome analysis has revealed that 15% of gorillas' genetic code is closer between humans and gorillas than it is between humans and chimpanzees.
Photograph: Luanne Cadd
First full sequence of gorilla genome shows 96% share with humans, with close parallels in sensory perception and hearing
Alok Jha, science correspondent
guardian.co.uk, Wednesday 7 March 2012 13.00 EST
Humans and gorillas last shared a common ancestor 10 million years ago, according to an analysis of the first full sequence of the gorilla genome. The gorilla is the last of the living great apes – humans, chimpanzees, gorillas and orangutans – to have its complete genetic code catalogued.
Scientists, led by researchers from the Wellcome Trust Sanger Institute near Cambridge and Baylor College of Medicine in Houston, also found that 15% of the gorilla's genetic code is closer between humans and gorillas than it is between humans and chimpanzees, our closest animal relative. The genomes of all three species are, in any case, highly similar: humans and chimpanzees share more than 98% of their genes, while humans and gorillas share more than 96%.
The genetic sequence was taken from a female western lowland gorilla (Gorilla gorilla gorilla) named Kamilah and published in Nature.
An initial analysis also showed similarities in genes involved in sensory perception and hearing, and brain development showed accelerated evolution in all three species. Genes associated with proteins that harden up skin were also particularly active in gorillas – which goes some way to explaining the large, tough knuckle pads on gorillas' hands.
"Gorillas are an interesting animal in their own right but the main reason they are of particular interest is because of their evolutionary closeness to us," said Aylwyn Scally, an author of the research from the Wellcome Trust Sanger Institute. "They're our second-closest evolutionary cousins after chimpanzees and knowing the content of the gorilla genome enables us to say quite a lot about an important period in human evolution when we were diverging from chimpanzees."
Comparing the sequences of humans, chimpanzees and gorillas has enabled scientists to put a more accurate clock on when the three species split from their last common ancestors. It was traditionally thought that the emergence of new species (known as "speciation") happens at a relatively localised point in time but emerging evidence suggests that this is not necessarily the case, that species split over an extended period. Studying the gorilla genome suggests that the divergence of gorillas from the common ancestor of humans and chimpanzees happened around 10 million years ago. Humans and chimpanzees last shared a common ancestor around 6 million years ago. Eastern and western gorillas split some time in the last million years.
One curious find was the evolution of genes associated with hearing, which seem very similar between humans and gorillas. "Scientists had suggested that the rapid evolution of human hearing genes was linked to the evolution of language," said Chris Tyler-Smith, senior author from the Wellcome Trust Sanger Institute. "Our results cast doubt on this, as hearing genes have evolved in gorillas at a similar rate to those in humans."
Scally adds that it could well be that there has been a parallel acceleration in these genes for two entirely different reasons – that human hearing has developed because of speech and gorilla hearing has developed to serve an entirely different, but as-yet-unknown, purpose.
The researchers said that studying the gorilla genome would shed light on a time when apes were fighting for survival across the world.
"There's an interesting background story of great ape evolution," says Scally. "The common ancestor of all four great apes was sometime back in 15 to 20 million years ago. At that time, it seems to have been a nice time to have been an ape – it was a golden age – a lot of the world was just right for the kind of environment for apes to live in. Since that time, the story has been of fragmentation and extinction – most of the great ape species that have existed have gone. Today, all the non-human apes are really endangered populations, they're living in forest refuges and population numbers are quite low. Humans look like an exception to that – we're all over the world now and live in places where you could never have had a primate beforehand."
Today, gorillas are classified as critically endangered and populations have plummeted to below 100,000 individuals in recent decades due to poaching and disease. They are restricted to equatorial forests in countries including Cameroon, Central African Republic, Gabon, Nigeria, Republic of Congo and Angola.
"As well as teaching us about human evolution, the study of great apes connects us to a time when our existence was more tenuous," say the researchers in Nature. "And in doing so, highlights the importance of protecting and conserving these remarkable species."
© 2012 Guardian News and Media Limited
http://www.guardian.co.uk/science/2012/mar/07/gorilla-genome-analysis-new-human-link
===
Gorillas More Related to People Than Thought, Genome Says
Surprising differences include gene that aids knuckle walking
March 7, 2012
http://news.nationalgeographic.com/news/2012/03/120306-gorilla-genome-apes-humans-evolution-science/ [with comment]
===
Gorilla genome sheds new light on human evolution
By Kate Kelland
LONDON | Wed Mar 7, 2012 3:25pm EST
LONDON (Reuters) - Scientists have sequenced the genome of the gorilla, the last great ape to have its genes decoded, and say it gives new insights into differences between the apes and humans -- including their ability to produce competitive sperm.
While confirming that our closest relative is the chimpanzee, the research also shows that around 15 percent of the human gene map resembles the gorilla more closely than it does the chimpanzee genome.
Chris Tyler-Smith, who worked with a team of scientists who presented their findings in a telephone briefing, said that while many human genes are similar to the gorilla versions, it is the ones that differ that are often most intriguing.
One difference that stuck out was in the genes involved in sperm production, he said.
"Gorillas live in groups with one male and lots of females, so there's not much opportunity for sperm competition," he explained. "It was interesting for us to see that some genes involved in sperm formation...had either become inactive in gorillas or had decreased in copy number."
The study was published in the journal Nature on Wednesday.
Gorillas survive in just a few isolated and endangered populations in the equatorial forests of central Africa. There are two distinct species, one known as the eastern lowland and mountain gorillas, and the other known as western lowland and cross river gorillas.
The team used DNA from a western lowland gorilla, named Kamilah, to assemble a gorilla genome sequence and then compared it with the gene maps of the other great apes.
They also sampled DNA sequences from other gorillas so they could explore genetic differences between gorilla species.
"The gorilla genome is important because it tells us about that crucial time when we were diverging from our closest evolutionary cousins," said Aylwyn Scally of Britain's Wellcome Trust Sanger Institute, who led the research team.
The human genome project was completed in 2003, while the chimpanzee gene map was published in 2005 and the orangutan genome was completed in 2011.
"Comparisons between these can help us explore the origins of humans when we separated from the great ape species in Africa between 6 and 10 million years ago," said Richard Durbin, who also worked on the study at the Sanger Institute.
The team searched more than 11,000 genes in human, chimpanzee and gorilla for genetic changes important in evolution. They found as expected that humans and chimpanzees are genetically closest to each other over most of the genome, but they found many places where this is not the case.
In all three species, genes relating to sensory perception, hearing and brain development showed accelerated evolution, the researchers said, particularly in humans and gorillas.
The team found that divergence of gorillas from humans and chimpanzees happened around ten million years ago, but the split between eastern and western gorillas was much more recent and more gradual. They compared this split to the one between chimpanzees and bonobos, or modern humans and Neanderthals.
SOURCE: Nature, March 8, 2012 [ http://www.nature.com/nature/journal/v483/n7388/full/nature10842.html ( http://bit.ly/wMPeyt )].
Copyright 2012 Reuters
http://www.reuters.com/article/2012/03/07/us-gorilla-genome-sheds-new-light-human-idUSTRE8261VA20120307 [with comment]
===
Gorilla genome could hold key to the human condition
Video [embedded]
Researchers in Cambridge can now compare human DNA with that of all the other apes
By Pallab Ghosh
Science correspondent, BBC News
7 March 2012 Last updated at 13:03 ET
Researchers in Cambridge have deciphered the genetic code of the gorilla - the last of the Great Ape genuses to be sequenced.
Writing in the journal Nature, the scientists say that researchers can now begin to examine the similarities and differences between the apes.
Genome sequences of humans, chimpanzees and orangutans are already published.
The team hopes their work will help to uncover genetic mutations that led to language, culture and science.
"I'd like to think that in the next 20 or 30 years we will get a deeper understanding of what happened genetically in our evolutionary history, and of how those genes affect the brain and other properties that make us modern humans," said Richard Durbin of the Wellcome Trust Sanger Institute, who led the study.
Initial comparisons confirm that chimpanzees are our closest relatives, sharing 99% of our DNA. Gorillas come a close second with 98%, and orangutans third with a 97% share.
That reflects the evolutionary history of apes. Genome comparison indicates that the human lineage separated from orangutans 14 million years ago, gorillas 10 million years ago, and chimps 6 million years ago.
That order of events is not a surprise, but the dates are earlier than many scientists had thought.
Although on average we are closest to chimps, many of our individual genes are more like those of gorillas.
Among them is a gene that enables us and gorillas to hear better than other apes.
Until now, some scientists had thought that the development of hearing was what enabled us to develop language - but as a result of this research, we now know this theory is wrong.
Fifteen percent of the human genome is closer to the gorilla than the chimpanzee, and 15% of the chimpanzee genome is closer to the gorilla than to humans.
One genetic difference that will be of interest to medical researchers is a mutation that results in dementia in humans, but seems to leave gorillas completely unaffected.
Rapid emergence
The genome unravelled in the research came from a female western lowland gorilla (Gorilla gorilla gorilla) called Kamilah.
The study shows that humans are more similar to gorillas than previously thought
Researchers searched through more than 11,000 genes in her genome, as well as in the published versions of the human, chimp and orangutan genetic codes, for changes important in evolution.
"Our most significant findings reveal not only differences between the species, reflecting millions of years of evolutionary divergence, but also similarities in parallel changes over time since their common ancestor," said Chris Tyler-Smith, who works with Dr Durbin.
Comparative studies will also shed more light on the evolution of all the Great Apes; but the key question is whether the bounty of genetic information contains clues to the moment when the first genes emerged that made humans capable of abstract thought.
"This is the question we are all fascinated by," Dr Durbin told BBC News.
It is unlikely that a single development led to our species' advance towards modernity, or that all developments along that path were genetic.
Anatomically modern humans (Homo sapiens) emerged around 200,000 years ago, but it was not until about 50,000 years ago that our bigger brains began to make a difference.
Until then, humanity was one among small number of apes in Africa, probably living not very differently from gorillas.
Gorilla and human skulls: how did the human brain evolve to be capable of abstract thought?
So, something happened very rapidly around that time that led to the emergence of abstract thought, allowing humans to invent advanced tools and use them to shape the environment.
"There will have been genetic factors," said Dr Durbin, "but also cultural and historic factors."
The one Great Ape not to be sequenced so far is the bonobo, a close relative of the chimp. That project is underway, and scientists expect its genome and that of the chimp to be very similar.
The availability of the genomes of all the Great Apes will help scientists answer what happened over the past 200,000 years to enable our species become what we are now.
*
Related Stories
How man 'lost his penile spines' 09 MARCH 2011, SCIENCE & ENVIRONMENT
http://www.bbc.co.uk/news/science-environment-12689692
Orangutan genome 'evolved slowly' 27 JANUARY 2011, SCIENCE & ENVIRONMENT
http://www.bbc.co.uk/news/science-environment-12286281
Most human gene variations mapped 27 OCTOBER 2010, SCIENCE & ENVIRONMENT
http://www.bbc.co.uk/news/science-environment-11632164
Apes 'extinct in a generation' 31 AUGUST 2005, SCI/TECH
http://www.bbc.co.uk/2/hi/science/nature/4202734.stm
Related Internet links
Nature
http://www.nature.com/
Sanger Institute
http://www.sanger.ac.uk/
*
BBC © 2012
http://www.bbc.co.uk/news/science-environment-17239059
===
Gorilla joins the genome club
Sequencing of gorilla genome adds to understanding of our evolutionary path
07 March 2012
http://www.nature.com/news/gorilla-joins-the-genome-club-1.10185
*
Insights into hominid evolution from the gorilla genome sequence
Published online 07 March 2012
http://www.nature.com/nature/journal/v483/n7388/full/nature10842.html
Greensburg, KS - 5/4/07
"Eternal vigilance is the price of Liberty."
from John Philpot Curran, Speech
upon the Right of Election, 1790
F6
Join the InvestorsHub Community
Register for free to join our community of investors and share your ideas. You will also get access to streaming quotes, interactive charts, trades, portfolio, live options flow and more tools.
