Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Studies on human genome variation provide insight into disease

27.10.2005


The International HapMap Project was initiated with the primary goal of facilitating medical studies and understanding the genomic basis for human diseases. To coordinate with the journal Nature’s publication describing the HapMap, the journal Genome Research is announcing a special issue entitled "Human Genome Variation," which is entirely devoted to studies using these data to provide insight into human biology and disease.



Predicting pregnancy success

Successful human reproduction and the maintenance of early pregnancy are dependent on a cluster of genes on chromosome 19 called the Luteinizing Hormone/Chorionic Gonadotropin Beta (LHB/CGB). During primate evolution, this cluster actively underwent numerous gene duplications and structural rearrangements, allowing the associated genes to acquire new biological functions.


In this month’s issue of Genome Research, Dr. Maris Laan and her colleagues report their analysis of the LHB/CGB cluster in three human populations: European Estonians, African Mandenka, and Chinese Han. They demonstrate how gene conversion was critical for shaping the genetic diversity of this region in humans.

"This study paves the way for examining an individual’s potential reproductive success based on sequence variants of the LHB/CGB genes," explains Laan. "We may be able to determine whether an individual is particularly susceptible to spontaneous abortions or reduced gonadal function, for example."

Contact:
Maris Laan, Ph.D.
Research Professor, University of Tartu, Estonia
Phone: +372-53495258
E-mail: maris@ebc.ee

X-ing out hereditary prostate cancer

According to the Prostate Cancer Foundation, one of every six American men develops prostate cancer, making it the most common form of non-skin cancer. Growing evidence suggests that there is a significant hereditary component to the disease, and one of the most strongly associated genomic regions lies on the X chromosome.

This X chromosomal region spans a cluster of five SPANX genes that are predominantly expressed in the testis and in certain tumors. In this month’s issue of Genome Research, Dr. Vladimir Larionov and his colleagues examined the genetic architecture of the SPANX cluster and showed how the region exhibited dynamic deletions, duplications, and gene conversion events, some of which may have resulted in the development of mutations involved in prostate cancer susceptibility.

"Because of the strong similarity among genes in this region, we had to develop a new technique for our mutational analysis, which we call TAR cloning," explains Larionov. "Using this method, we isolated the SPANX region from 200 individuals by recombination in yeast."

Based on their results, the authors speculate that predisposition to prostate cancer – at least in some individuals – is determined by the specific architecture of the SPANX gene cluster on the X chromosome. "We’re hoping to clarify which specific types of genomic rearrangements lead to prostate cancer susceptibility," says Larinov, "so that we can someday identify therapeutic targets for this disease."

Contact:
Vladimir Larionov, Ph.D.
Head, Genome Structure and Function Section, National Cancer Institute
Phone: 301-496-7941
E-mail: larionov@mail.nih.gov

Genetic traffic in DiGeorge syndrome

One of the most common human genomic disorders, DiGeorge syndrome, occurs in one of every 2,000-4,000 live births and involves a deletion on chromosome 22. The deletion is mediated by rare repetitive sequences that flank genes crucial for proper development of the heart, face, and upper thorax.

Dr. Bernice Morrow and her colleagues describe in this month’s issue of Genome Research how they examined these flanking repetitive sequences for patterns of polymorphisms. "Our results show that there are intervals with more frequent traffic of genetic material – regions with higher rates of gene conversion or recombination – that are indicative of genomic instability," explains Morrow.

"With this knowledge in hand, we hope to screen our patients and identify the genomic mechanism underlying this important disease," says Morrow.

Contact:
Bernice Morrow, Ph.D.
Professor, Albert Einstein College of Medicine
Phone: 718-430-4274
E-mail: morrow@aecom.yu.edu

Looking for genes in all the right places

Geneticists rely on variation, or alterations in DNA sequence, for disease-association studies. Hereditary traits such as heart disease, arthritis, and Alzheimer’s can be assigned to specific genomic regions based on their association with DNA markers.

The success of disease-association studies is dependent upon several characteristics of the DNA markers, including allelic frequency and genomic coverage. In some cases, a particular variant at one locus is perfectly associated with a specific variant at another locus; in other words, the two markers are "genetically indistinguishable."

Dr. Lon Cardon and his colleagues describe in this month’s issue of Genome Research how these "genetically indistinguishable" polymorphisms can complicate the identification of disease-related genes. "Although they should pose few difficulties when they are located close together on the same chromosome, they often occur on different chromosomes, where it is quite another story," explains Cardon. When this is the case, true disease genes cannot be distinguished from their anonymous genetic ’twins.’

"Research in human genetic variation is rapidly moving towards realizing our aims of improving diagnosis of common diseases such as diabetes and heart disease," says Cardon, "but the genome is tricky; it won’t reveal its secrets easily. The real disease-causing culprits can have many silent partners. We need to know the relationships of all these partners to focus on real disease mutations and to minimize attention on the innocent gene variants that colour the humanity of life."

Contact:
Lon R. Cardon, Ph.D.
Professor of Bioinformatics, University of Oxford
Phone: +44-01865-287591
E-mail: lon.cardon@well.ox.ac.uk

Maria A. Smit | EurekAlert!
Further information:
http://www.cshl.edu

More articles from Studies and Analyses:

nachricht Real-time feedback helps save energy and water
08.02.2017 | Otto-Friedrich-Universität Bamberg

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Safe glide at total engine failure with ELA-inside

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded after a glide flight with an Airbus A320 in ditching on the Hudson River. All 155 people on board were saved.

On January 15, 2009, Chesley B. Sullenberger was celebrated world-wide: after the two engines had failed due to bird strike, he and his flight crew succeeded...

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

New pop-up strategy inspired by cuts, not folds

27.02.2017 | Materials Sciences

Sandia uses confined nanoparticles to improve hydrogen storage materials performance

27.02.2017 | Interdisciplinary Research

Decoding the genome's cryptic language

27.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>