Humans, chimpanzees and monkeys share DNA but not gene regulatory mechanisms

Nov 06, 2012

Humans share over 90% of their DNA with their primate cousins. The expression or activity patterns of genes differ across species in ways that help explain each species' distinct biology and behavior.

DNA factors that contribute to the differences were described on Nov. 6 at the American Society of Human Genetics 2012 meeting in a presentation by Yoav Gilad, Ph.D., associate professor of human genetics at the University of Chicago.

Dr. Gilad reported that up to 40% of the differences in the expression or activity patterns of genes between humans, chimpanzees and rhesus monkeys can be explained by regulatory mechanisms that determine whether and how a gene's recipe for a protein is transcribed to the RNA molecule that carries the recipe instructions to the sites in cells where proteins are manufactured.

In addition to improving scientific understanding of the uniqueness of humans, studies such as the investigation conducted by Dr. Gilad and colleagues could have relevance to human health and disease.

"Through inter-species' comparisons at the DNA sequence and expression levels, we hope to identify the genetic basis of human specific traits and in particular the genetic variations underlying the higher susceptibility to certain diseases such as malaria and cancer in humans than in non-human primates," said Dr. Gilad.

Dr. Gilad and his colleagues studied gene expression in lymphoblastoid cell lines, laboratory cultures of immortalized , from eight humans, eight chimpanzees and eight .

They found that the distinct of the three species can be explained by corresponding changes in genetic and epigenetic regulatory mechanisms that determine when and how a gene's is transcribed to a (mRNA) molecule.

Dr. Gilad also determined that the epigenetics process known as histone modification also differs in the three species. The presence of histone marks during gene transcription indicates that the process is being prevented or modified.

"These data allowed us to identify both conserved and species-specific enhancer and repressor regulatory elements, as well as characterize similarities and differences across species in transcription factor binding to these regulatory elements," Dr. Gilad said.

Among the similarities among the three species were the promoter regions of DNA that initiated transcription of a particular gene.

In all three species, Dr. Gilad's lab found that transcription factor binding and histone modifications were identical in over 67% of regulatory elements in DNA segments that are regarded as promoter regions.

Explore further: Team advances genome editing technique

More information: The researchers presentation is titled, "Genome-wide comparison of genetic and epigenetic regulatory mechanisms in primates."

Related Stories

Controlling patterns of DNA methylation

Oct 28, 2011

A study performed by scientists in Dirk Schübeler's team at the Friedrich Miescher Institute for Biomedical Research in Basel identifies DNA sequences that autonomously determine DNA methylation patterns. ...

'Junk DNA' defines differences between humans and chimps

Oct 25, 2011

For years, scientists believed the vast phenotypic differences between humans and chimpanzees would be easily explained – the two species must have significantly different genetic makeups. However, when ...

Recommended for you

Team advances genome editing technique

Oct 21, 2014

Customized genome editing – the ability to edit desired DNA sequences to add, delete, activate or suppress specific genes – has major potential for application in medicine, biotechnology, food and agriculture.

Studies steadily advance cellulosic ethanol prospects

Oct 20, 2014

At the Agricultural Research Service's Bioenergy Research Unit in Peoria, Illinois, field work and bench investigations keep ARS scientists on the scientific front lines of converting biomass into cellulosic ...

User comments : 0