Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Second phase of HapMap project is completed

18.10.2007
Database of human genetic diversity allows identification of disease-associated genes

Investigators from six countries have completed the second phase of the International HapMap Project, an effort to identify and catalog genetic similarities and differences among populations around the world. Information provided in the first phase of the HapMap, completed in 2005, has led to the development of techniques facilitating the search for genes associated with common diseases – such as schizophrenia and heart disease – and the identification of more than 50 such disease-associated genes.

In the past year, using data and methods based on the HapMap, MGH researchers have published new genetic contributors to conditions such as type 2 diabetes, Crohn’s disease, elevated blood cholesterol, rheumatoid arthritis, multiple sclerosis, and prostate cancer. These studies and many others used a suite of analytical methods developed at MGH and its partner institutions.

“The original HapMap provided the backbone for genome-wide association studies that have uncovered previously unsuspected genetic components of many diseases, leading to new areas of research,” says Mark Daly, PhD, of the Massachusetts General Hospital (MGH) Center for Human Genetic Research, co-senior author of the report in the Oct. 18 issue of Nature. “The second phase has tripled the amount of genetic variation assessed and describes up to 95 percent of common single-letter variations in the human genetic code.”

While the Human Genome Project confirmed that the more than 3 billion “letters” of DNA in each human were 99.9 percent identical, analyzing the small fraction that differ – including about 10 million distinct, single-letter variations, also called SNPs – remained a daunting task. In 2001 Daly and colleagues showed that adjacent DNA variations are inherited together in segments called haplotypes, with the boundaries between adjacent segments defined by locations of enhanced recombination – the shuffling of DNA segments between the chromosomes inherited from each parent. Based in part on those findings, the HapMap project was started to create a map of SNPs and haplotypes across the genomes of 270 individuals from Nigeria, China, Japan and the U.S. While the first phase identified and cataloged about 1.3 million SNPs, the second phase has brought the total to more than 3.1 million SNPs catalogued in the same population.

“The increased density of identified SNPs in the second phase has allowed us to much more specifically understand the nature of these recombination ‘hotspots.’ ” says Daly. “Another interesting finding is that we can identify, among apparently unrelated individuals, chromosome segments that clearly have been inherited without change from common ancestors who lived hundreds to a thousand years ago. The ability to detect these more recently inherited segments of DNA may hold the key to rare disease-associated variations that have been hard to detect with current tools.” Daly is an assistant professor of Medicine at Harvard Medical School and a senior associate member of the Broad Institute of Harvard and Massachusetts Institute of Technology.

The information in the HapMap is freely accessible to researchers around the world. The data assembled in the second phase was added to the public database as it became available and already has been used in a number of research studies. As the project continues, it will use new sequencing techniques to further analyze genetic variations in the same study group and in a larger population.

“While the completion of Phase 2 of the HapMap Project makes possible comprehensive studies of common SNPs in the sampled populations, there remains much work to be done,” says David Altshuler, of the MGH Center for Human Genetic Research. “Current efforts aim to catalogue genetic variation in more diverse samples from around the world, to define larger chromosomal alterations that might be missed by SNPs-based approaches and to find rare genetic variations that might have potent effects on individual patients. Only by combining all these approaches can we hope to have a complete understanding of the genetic root causes of common human diseases.” Altshuler is also an associate professor of Genetics and Medicine at HMS, director of the Program in Medical and Population Genetics at the Broad Institute, and co-chair for Analysis of the International HapMap Project.

Sue McGreevey | EurekAlert!
Further information:
http://www.hapmap.org

Further reports about: Broad Institute DNA Daly Genetic HapMap MGH SNP genetic variation segments

More articles from Life Sciences:

nachricht Molecular Force Sensors
20.09.2017 | Max-Planck-Institut für Biochemie

nachricht Foster tadpoles trigger parental instinct in poison frogs
20.09.2017 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

Im Focus: Fast, convenient & standardized: New lab innovation for automated tissue engineering & drug

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.

MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...

Im Focus: Silencing bacteria

HZI researchers pave the way for new agents that render hospital pathogens mute

Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Molecular Force Sensors

20.09.2017 | Life Sciences

Producing electricity during flight

20.09.2017 | Power and Electrical Engineering

Tiny lasers from a gallery of whispers

20.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>