Redesigning Animal Agriculture

50 R. Tellam
remaining 98.5% has not been thoroughly
explored but this non-coding DNA is likely
to contain complex gene expression regulatory
information and perhaps quite a few
surprises as well.
The Bovine Genome Sequencing Project
The bovine genome consists of 29 pairs
of autosomal chromosomes and an X
and Y chromosome collectively containing
approximately 2.7 billion base pairs
of DNA. The plasticity of this genome is
evident in the phenotypic diversity of the
many bovine breeds which have become
specialized for milk and meat production,
ability to work and carry heavy loads, and
to prosper in tropical environments in the
presence of continuous parasite challenges.
This specialization is relatively recent in
the timescale of evolution of the species
and reflects intense selection pressures on
the breeding populations.
The Bovine Genome Sequence Project
(BGSP) was born out of the Human Genome
Project (HGP) and capitalized on its massive
infrastructure investments and know-how
at a time when the costs of DNA sequencing
were dramatically decreasing due to
technological innovations and industrial-
scale management. It was also widely recognized
that mammals have very similar
complements of genes and thus the bovine
genome sequence would allow capture of
the enormous wealth of functional information
associated with human and rodent
genes. A discussion paper, authored by
Richard Gibbs, George Weinstock, Steven
Kappes, Lawrence Schook, Loren Skow and
Jim Womack, proposing the sequencing of
the bovine genome was submitted to the
National Human Genome Research Institute
(NHGRI) in 2002 and it was favourably
received, but commencement of the pro ject
was dependent on raising the necessary
finances (NHGRI, 2005b).
The BGSP was formally initiated in
December 2003 by an international consortium
of research organizations and funding
agencies at a total cost of US$53 million.
The consortium includes: the National
Human Genome Research Institute (USA);
CSIRO (Australia); the US Department of
Agriculture; the State of Texas; Genome
Canada; New Zealand’s Agritech Investments
Ltd, Dairy Insight Inc and AgResearch Ltd;
the Kleberg Foundation (USA); and the
National, Texas and South Dakota Beef
Check-off Funds (USA). The sequencing
and assembly of the bovine genome is being
undertaken at the Baylor College of Medicine,
Human Genome Sequencing Center (USA)
and the Michael Smith Genome Science
Centre (Vancouver, Canada). Both the HGP
and BGSP were undertaken by public consortia
with a strong commitment to early
release of sequence data as significant scientific
pro gress can be made even with partial
and fragmentary sequence information. The
project is driven by a sense of scientific discovery
and involves a large group of scientists
with an enormous wealth of technical
expertize and biological knowledge.
The specific motivations for the BGSP
at its commencement were multifaceted.
It was reasoned that the cow sequence
could be used to better identify functional
regions in the human genome sequence
through comparison of the human, rodent
(murine and rat) and bovine sequences
(Collins et al., 2003). It was also recognized
that the cow could be used directly
as a model for some human diseases and
in some instances to discover disease-causing
genes. One example is a mutation in
the limbin gene in Japanese Brown cattle
that was shown to cause chondrodysplastic
dwarfism (Takeda et al., 2002). This discovery
facilitated the identification of a mutation
in the human orthologue that results in
a similar genetic disease in humans (Ruiz-
Perez et al., 2000; Galdzicka et al., 2002).
Perhaps the power of this type of approach
will be more fully apparent for complex
cattle traits such as muscling, disease resistance
and feed conversion efficiency, which
may better inform human disorders such as
sarcopena, susceptibility to disease, obesity
and type II diabetes. The cohabitation
of humans and livestock for thousands of
years has resulted in disease interchange
that has helped to mould the evolution of