Cross-species strategy might be a powerful tool for studying human disease

Feb 03, 2011

A new study takes advantage of genetic similarities between mammals and fruit flies by coupling a complex genetic screening technique in humans with functional validation of the results in flies. The new strategy, published by Cell Press on February 3rd in The American Journal of Human Genetics, has the potential to be an effective approach for unraveling genetically complex human disorders and providing valuable insights into human disease.

Genome-wide association studies (GWASs) involve sifting through the complete set of DNA from many individuals to identify genetic variations associated with a particular disease. Although this technique has proven to be a powerful tool for developing a better understanding of diseases, such as Alzheimer's disease (AD), that involve multiple genetic variations, there are substantial limitations. Perhaps most significantly, follow-up studies aimed at validating disease-associated genetic variations in humans require large sample sizes and a great deal of effort. The current study validates GWAS results by using an inventive alternative approach.

"Simple genetic models of human disease, such as in the fruit fly, have been important experimental tools for many years, particularly for large-scale functional testing of genes," explains a senior study author, Mel B. Feany, MD, PhD, from Brigham and Women's Hospital.. "We therefore hypothesized that the fly disease model might fulfill the growing need for efficient strategies for validation of association signals identified by GWAS."

Dr. Joshua M. Shulman and colleagues implemented a two-stage strategy to enhance a GWAS of AD neuropathology by integrating the results of gene discovery in humans with functional screening in a fly model system relevant to AD biology. Specifically, the researchers evaluated 19 genes from 15 distinct genomic regions identified in a human GWAS designed to identify genes that influence AD pathology. In six out of these 15 genomic regions, a causal gene was subsequently identified in the fly disease model on the basis of interactions with the neurotoxicity of Tau protein, a well-known constituent of AD pathology.

The authors also discuss the potential for application of their technique to studies examining other human diseases. "Evidence is emerging in support of a polygenic model of inheritance for complex genetic disorders, particularly neuropsychiatric diseases, in which hundreds or even thousands of common gene variants collectively contribute to disease risk," says co-author Philip L. De Jager, MD, PhD, also of Brigham and Women's Hospital. "Our strategy of coupling human GWAS with functional in a model organism will likely be a powerful strategy for follow-up of such signals in the future in order to prioritize genes and pathways for further investigation."

Explore further: Down's chromosome cause genome-wide disruption

add to favorites email to friend print save as pdf

Related Stories

Refined tools help pinpoint disease-causing genes

Apr 29, 2010

In findings that may speed the search for disease-causing genes, a new study challenges the prevailing view that common diseases are usually caused by common gene variants (mutations). Instead, say genetics researchers, the ...

Recommended for you

Down's chromosome cause genome-wide disruption

1 hour ago

The extra copy of Chromosome 21 that causes Down's syndrome throws a spanner into the workings of all the other chromosomes as well, said a study published Wednesday that surprised its authors.

Research uncovers DNA looping damage tied to HPV cancer

7 hours ago

It's long been known that certain strains of human papillomavirus (HPV) cause cancer. Now, researchers at The Ohio State University have determined a new way that HPV might spark cancer development – by ...

New therapy against rare gene defects

Apr 15, 2014

On 15th April is the 1st International Pompe Disease Day, a campaign to raise awareness of this rare but severe gene defect. Pompe Disease is only one of more than 40 metabolic disorders that mainly affect children under ...

User comments : 0

More news stories

Down's chromosome cause genome-wide disruption

The extra copy of Chromosome 21 that causes Down's syndrome throws a spanner into the workings of all the other chromosomes as well, said a study published Wednesday that surprised its authors.

Ebola virus in Africa outbreak is a new strain

The Ebola virus that has killed scores of people in Guinea this year is a new strain—evidence that the disease did not spread there from outbreaks in some other African nations, scientists report.

Freight train industry to miss safety deadline

The U.S. freight railroad industry says only one-fifth of its track will be equipped with mandatory safety technology to prevent most collisions and derailments by the deadline set by Congress.