What have we got in common with a Gorilla?

An insight into human evolution from the gorilla genome sequence

What have we got in common with a Gorilla?

gorilla.jpgSan Diego Zoo
Kamilah the Gorilla.

Researchers announce today (7 March 2012) that they have completed the genome sequence for the gorilla - the last genus of the living great apes to have its genome decoded. While confirming that our closest relative is the chimpanzee, the team show that much of the human genome more closely resembles the gorilla than it does the chimpanzee genome.

This is the first time scientists have been able to compare the genomes of all four living great apes: humans, chimpanzees, gorillas and orang-utans. This study provides a unique perspective on our own origins and is an important resource for research into human evolution and biology, as well as for gorilla biology and conservation.

"The gorilla genome is important because it sheds light on the time when our ancestors diverged from our closest evolutionary cousins. It also lets us explore the similarities and differences between our genes and those of gorilla, the largest living primate. Using DNA from Kamilah, a female western lowland gorilla, we assembled a gorilla genome sequence and compared it with the genomes of the other great apes. We also sampled DNA sequences from other gorillas in order to explore genetic differences between gorilla species."

Aylwyn Scally, first author from the Wellcome Trust Sanger Institute

The team searched more than 11,000 genes in human, chimpanzee and gorilla for genetic changes important in evolution. Humans and chimpanzees are genetically closest to each other over most of the genome, but the team found many places where this is not the case. 15 per cent of the human genome is closer to the gorilla genome than it is to chimpanzee, and 15 per cent of the chimpanzee genome is closer to the gorilla than human.

In all three species, genes relating to sensory perception, hearing and brain development showed accelerated evolution - and particularly so in humans and gorillas.

"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. We found that gorillas share many parallel genetic changes with humans including the evolution of our hearing. Scientists had suggested that the rapid evolution of human hearing genes was linked to the evolution of language. Our results cast doubt on this, as hearing genes have evolved in gorillas at a similar rate to those in humans."

Dr Chris Tyler-Smith, senior author from the Wellcome Trust Sanger Institute

This research also illuminates the timing of splits between species. Although we commonly think of species diverging at a single point in time, this does not always reflect reality: species can separate over an extended period of time.

The team found that divergence of gorillas from humans and chimpanzees occurred around ten million years ago. The split between eastern and western gorillas was much more recent, in the last million years or so, and was gradual, although they are now genetically distinct. This split is comparable in some ways to the split between chimpanzees and bonobos, or modern humans and Neanderthals.

"Our research completes the genetic picture for overall comparisons of the great apes. After decades of debate, our genetic interpretations are now consistent with the fossil record and provide a way for palaeontologists and geneticists to work within the same framework."

"Our data are the last genetic piece we can gather for this puzzle: there are no other living great ape genera to study."

Dr Richard Durbin, senior author from the Wellcome Trust Sanger Institute

Gorillas survive today in just a few isolated and endangered populations in the equatorial forests of central Africa. They are severely threatened and their numbers are diminishing. This research not only informs us about human evolution, but highlights the importance of protecting and conserving the full diversity of these remarkable species.

Notes to Editors
Funding

Refer to paper for list of funding agencies.

Participating Centres

Refer to paper for list of participating centres.

Selected Websites
Contact the Press Office

Dr Samantha Wynne, Media Officer

Tel +44 (0)1223 492 368

Emily Mobley, Media Officer

Tel +44 (0)1223 496 851

Wellcome Trust Sanger Institute,
Hinxton,
Cambridgeshire,
CB10 1SA,
UK

Mobile +44 (0) 7900 607793

Recent News

Genome editing reveals role of gene important for human embryo development

CRISPR-Cas9 genome editing shows that the protein OCT4 is essential in very early days of human embryo development

Huge genetic diversity among Papuan New Guinean peoples revealed

Genetic diversity found to mirror linguistic and cultural diversity among Papuan New Guinean people

Immunotherapy treatment option for selected breast cancer patients, genetic study suggests

Opens up the possibility of another therapy option for approximately 1,000 breast cancer patients in the UK