Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Emory scientists develop new map of genetic variation in human genome

14.08.2006
Genome insertions and deletions (INDELs) provide expanded view of human genetic differences

Emory University scientists have identified and created a map of more than 400,000 insertions and deletions (INDELs) in the human genome that signal a little-explored type of genetic difference among individuals. INDELS are an alternative form of natural genetic variation that differs from the much-studied single nucleotide polymorphisms (SNPs). Both types of variation are likely to have a major impact on humans, including their health and susceptibility to disease.

The INDEL research, led by Scott Devine, PhD, assistant professor of biochemistry at Emory University School of Medicine, has been posted online and will be published in the September issue of the journal Genome Research.

The human genome sequence in our DNA contains three billion base pairs of four chemical building blocks Ð adenine, thymine, cytosine, and guanine (A, T, C, G), strung together in different combinations in long chains within 23 pairs of chromosomes. When the first human genome was being sequenced, it became apparent that additional human genomes would have to be sequenced to identify the places in the genetic code that account for human variation. Scientists now know that humans share about 97-99 percent of the genetic code, and the remaining 1-3 percent dictates individual differences. These naturally occurring differences, called polymorphisms, help explain differences in appearance, susceptibility to diseases, and responses to the environment.

SNPs are differences in single chemical bases in the genome sequence, and INDELs result from the insertion and deletion of small pieces of DNA of varying sizes and types. If the human genome is viewed as a genetic instruction book, then SNPs are analogous to single letter changes in the book, whereas INDELs are equivalent to inserting and deleting words or paragraphs.

Most polymorphism discovery projects have focused on SNPs, resulting in the International HapMap Project Ð a catalog and map of more than 10 million SNPs derived from diverse individuals throughout the globe. Dr. Devine and postdoctoral researcher Ryan Mills, PhD, focused instead on INDELs, using a computational approach to examine DNA re-sequences that originally were generated for SNP discovery projects. Thus far they have identified and mapped 415,436 unique INDELs, but they expect to expand the map to between 1 and 2 million by continuing their efforts with additional human sequences.

Dr. Devine says INDELs can be grouped into five major categories, depending on their effect on the genome: (1) insertions or deletions of single base pairs; (2) expansions by only one base pair (monomeric base pair expansions); (3) multi-base pair expansions of 2 to 15 repeats; (4) transposon insertions (insertions of mobile elements); (5) and random DNA sequence insertions or deletions. INDELs already are known to cause human diseases. For example, cystic fibrosis is frequently caused by a three-base-pair deletion in the CFTR gene, and DNA insertions called triplet repeat expansions are implicated in fragile X syndrome and Huntington's disease. Transposon insertions have been identified in hemophilia, muscular dystrophy and cancer.

"Were entering an exciting new era of predictive health where an individuals personal genetic code will provide guidance on healthcare decisions says Dr. Devine. "Our maps of insertions and deletions will be used together with SNP maps to create one big unified map of variation that can identify specific patterns of genetic variation to help us predict the future health of an individual. The next phase of this work is to figure out which changes correspond to changes in human health and develop personalized health treatments. This could include specific drugs tailored to each individual, given their specific genetic code.

Ultimately, each person's genome could be re-sequenced in a doctor's office and his or her genetic code analyzed to make predictions about their future health. Dr. Devine believes the technology holds the promise of predicting whether a person will develop diabetes, mental disorders, cancer, heart disease and a range of other conditions.

Holly Korschun | EurekAlert!
Further information:
http://www.emory.edu

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>