Functional Genomics of the Chicken

With Its Genome Sequenced and High-Throughput Genomic Research Tools Available, the Chicken Has Achieved Model Organism Status, Opening Up New Research Opportunities for Poultry Scientists and Biomedical Researchers – The Possibility Now Exists of Modifying the Phenotype of the Chicken to Fit Defined Production Goals.

Road Map for Exploration of Chicken Genome Now in Place, According to New Review of Functional Genomics of the Chicken.

With
Its Genome Sequenced and High-Throughput Genomic Research Tools
Available, the Chicken Has Achieved Model Organism Status, Opening Up
New Research Opportunities for Poultry Scientists and Biomedical
Researchers – The Possibility Now Exists of Modifying the Phenotype of
the Chicken to Fit Defined Production Goals.

An invited review
article in the current issue of Poultry Science describes, according to
its authors, “the recent ascent of the chicken to model organism
status” and provides “a road map for the large-scale exploration of the
chicken genome.”

The article, “Functional Genomics of the
Chicken: A Model Organism” appears in the October 1, 2007 issue of
Poultry Science, a research journal published monthly by The Poultry
Science Association (PSA), and is authored by L. A. Cogburn, T. E.
Porter, M. J. Duclos, J. Simon, S. C. Burgess, J. J. Zhu, H. H. Cheng,
J. B. Dodgson, and J. Burnside. It is available to download free online
at: http://ps.fass.org/cgi/reprint/86/10/2059

The
article provides a detailed summary of the current status of research
employing functional genomics in chickens. It complements and is the
final chapter in a sequence of invited review papers on the movement
from genetics to genomics in poultry research. (The earlier articles
were published in the December 2006 issue of Poultry Science.)

The
earlier articles focused on variations in the structure of the genome
and associations with performance traits. The current paper focuses in
greater detail on variations in gene expression, and how these
variations relate to specific traits.

Model Organism Status: Potential Impact on Biomedical Research

According
to Susan J. Lamont, C.F. Curtiss Distinguished Professor, Iowa State
University, the article validates the chicken‚s status as a model
organism.

“Poultry scientists have long known the chicken’s
value as a research animal for investigations outside of poultry
science. The authors have confirmed this in the strongest way possible
by validating the chicken’s status as a model organism, and hence its
usefulness to the biomedical and general scientific community for
investigating scientific questions,” said Lamont.

Biomedical
researchers and poultry scientists focus on many overlapping questions
regarding biological development, growth and viral resistance, and at
an earlier time the chicken was commonly used for biomedical research.
The first anti-cancer vaccine, for example, was discovered using
poultry (against Marek’s disease). The later switch to the mouse as the
preferred biomedical research animal was, according to Lamont, driven
primarily by the availability of superior tools to investigate it.

“Since
the 2004 sequencing of the chicken genome and the development of
improved functional genomic tools to investigate it, the gap between
the mouse and chicken as model organisms for biomedical research has
now been eliminated. Understanding the functional genomics of the
chicken will make it much more attractive for biomedical researchers,”
said Lamont.

Powerful Tools for Genomic Research Create Opportunity to Modify Phenotype. Impact on Commercial Flocks Likely within 10 Years

Researchers
are now able to accelerate their efforts through the use of
microarrays, which allow scientists to examine changes in the
expression of all of a chicken’s genes simultaneously, rather than one
at a time. Microarrays, and other new technologies such as
marker-assisted selection, transgenics and RNA interference, give
scientists the opportunity, for the first time, to use molecular
genetics to modify the phenotype of the chicken to meet previously
defined production goals.

“The tremendous advances we have seen
in functional genomics should give us the opportunity to have a
positive impact on commercial flocks within a decade. We should begin
seeing the integration of phenotypic improvements into breeding
populations within 3-5 years, followed, after a typical lag time of
about four years, by their appearance in commercial populations,” said
Lamont.