Beyond base pairs: Regulatory sequences of mouse genome sequenced for first time

Jul 01, 2012
In a paper published in the July 1, 2012, issue of the journal Nature, researchers at the Ludwig Institute for Cancer Research and the University of California, San Diego School of Medicine open the book further, mapping for the first time a significant portion of the functional sequences of the mouse genome, the most widely used mammalian model organism in biomedical research. Credit: UC San Diego School of Medicine

Popularly dubbed "the book of life," the human genome is extraordinarily difficult to read. But without full knowledge of its grammar and syntax, the genome's 2.9 billion base-pairs of adenine and thymine, cytosine and guanine provide limited insights into humanity's underlying genetics.

In a paper published in the July 1, 2012 issue of the journal Nature, researchers at the Ludwig Institute for and the University of California, San Diego School of Medicine open the book further, mapping for the first time a significant portion of the functional sequences of the , the most widely used mammalian in biomedical research.

"We've known the precise alphabet of the for more than a decade, but not necessarily how those letters make meaningful words, paragraphs or life," said Bing Ren, PhD, head of the Laboratory of Gene Regulation at the Ludwig Institute for Cancer Research at UC San Diego. "We know, for example, that only one to two percent of the functional genome codes for proteins, but that there are highly conserved regions in the genome outside of protein-coding that affect genes and disease development. It's clear these regions do something or they would have changed or disappeared."

Chief among those regions are cis-regulatory elements, key stretches of DNA that appear to regulate the transcription of genes. Misregulation of genes can result in diseases like cancer. Using high-throughput sequencing technologies, Ren and colleagues mapped nearly 300,000 mouse cis-regulatory elements in 19 different types of tissue and cell. The unprecedented work provided a functional annotation of nearly 11 percent of the mouse genome, and more than 70 percent of the conserved, non-coding sequences shared with other , including humans.

As expected, the researchers identified different sequences that promote or start , enhance its activity and define where it occurs in the body during development. More surprising, said Ren, was that the structural organization of the cis-regulatory elements are grouped into discrete clusters corresponding to spatial domains. "It's a case of form following function," he said. "It makes sense."

While the research is fundamentally revealing, Ren noted it is also just a beginning, a partial picture of the functional genome. Additional studies will be needed in other types of cells and at different stages of development.

"We've mapped and understand 11 percent of the genome," said Ren. "There's still a long way to march."

Explore further: Battling superbugs with gene-editing system

Related Stories

Express yourself: How zygotes sort out imprinted genes

Feb 16, 2012

Writing in the February 17, 2012 issue of the journal Cell, researchers at the Ludwig Institute for Cancer Research, the University of California, San Diego School of Medicine and the Toronto Western Research Institute peel a ...

New technique reveals unseen information in DNA code

May 17, 2012

Imagine reading an entire book, but then realizing that your glasses did not allow you to distinguish "g" from "q." What details did you miss? Geneticists faced a similar problem with the recent discovery ...

Recommended for you

Project launched to study evolutionary history of fungi

13 hours ago

The University of California, Riverside is one of 11 collaborating institutions that have been funded a total of $2.5 million by the National Science Foundation for a project focused on studying zygomycetes – ancient li ...

Different watering regimes boost crop yields

16 hours ago

Watering tomato plants less frequently could improve yields in saline conditions, according to a study of the impact of water and soil salinity on vegetable crops.

Woolly mammoth genome sequencer at UWA

18 hours ago

How can a giant woolly mammoth which lived at least 200,000 years ago help to save the Tasmanian Devil from extinction? The answer lies in DNA, the carrier of genetic information.

User comments : 0