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Why a new genetics teaching tool?
Advances in genetics are providing insights into the basic workings of
life and tools to alter these processes. It is imperative that students
be given a solid grounding in genetics so that they can actively participate
in making decisions regarding the application of genetic tools to enhancing
human health, agricultural productivity, and the environment. Burgeoning
human populations and increasing urbanization mean that more food is
required yet fewer people know where food comes from. Students must
understand the role of agriculture in society in order to make rational
decisions regarding crop and animal production practices, including the
genetic manipulation of organisms through conventional breeding and
biotechnology. The Internet provides new ways to access and exchange
information and students must develop facility with these tools if
they are to have stimulating careers with opportunities for creativity
and contribution.
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Why barley?
Barley, (Hordeum vulgare), is one of the oldest
crops and it is the fourth most important cereal in the world. Barley
is also an ideal system for genetic analysis. This diploid
(2n = 14) species has seven cytologically distinct chromosomes,
over 1,000 genes and 500 translocation stocks are known,
and the crop has been the subject of intensive
genomics research.
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Why "Wolfe" barley?
Over
a period of nearly 30 years, Dr. Bob
Wolfe, a Canadian barley geneticist, worked on developing
recessive and dominant marker stocks for easily scored
phenotypes. He accomplished this feat by systematically
backcrossing dominant and recessive alleles, respectively,
into a recurrent genetic background adapted to his breeding
environment. The dominant and recessive parental stocks,
accordingly, represent genetic mosaics of a common genetic
background with contrasting introgressed segments
containing dominant and recessive alleles. Determining
the extent of these introgressed segments is one of the
objectives of the mapping aspect of this project. The
dominant and recessive parents were crossed and a population
of doubled
haploids was derived from the F1. Each doubled
haploid is a completely homozygous genotype that can be
repeatedly phenotyped and genotyped. Thus, the population
serves as an "immortal" genetic resource for
genetic analysis. We call this the population the "Oregon" Wolfe
Barleys because the doubled haploids were produced, and
are maintained, by the Oregon State University Barley Project.
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More on the Oregon Wolfe Barley
We
offer this population - the "Oregon Wolfe Barleys" -
as an interactive, collaborative, genetics instruction
and research tool. This site will serve as a resource for obtaining
seed, data retrieval,
and data reporting. This site will provide access to Triticeae genomics
resources.
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What data is currently available on the OWBs?
Plant
genome analysis uses molecular tools. The emphasis on DNA-level
variation is understandable, given the paucity of morphological
markers - "naked eye polymorphisms (NEPs)" -
and the lack, until now, of any significant number of readily
scoreable phenotypes in a single reference population.
As a starting point for genetics instruction, however,
NEPs have high visual impact, underscore phenotypes important
for agricultural production, and provide starting points
for comparative analysis of plant genomes. As a first step,
the readily scored NEPs provide an unparalleled teaching
tool for demonstrating the principles of Mendelian inheritance
in the context of a crop plant. Furthermore, these NEPs
provide an excellent starting point for a discussion of
crop evolution. The OWBs integrate NEPs with an array of
molecular markers including AFLPs, RAPDs, RFLPs, and SSRs. These
data are available to lead students through the important
transition from observed phenotype to genotype and will
provide a hands-on tool for automated linkage map construction.
The full power of this population as an interactive, collaborative
teaching and research tool will come as participants generate
additional genotype and phenotype data. Consider, for example,
a University lab generating abundant DNA-level polymorphism
while a high school science class measures plant height
and heading date. If each group operates in isolation,
the marker data generates just another map and the plant
growth data are just another quantitative data set. However,
through this collaborative network, the two can be integrated,
and through quantitative trait locus (QTL) analysis, the
determinants of the maturity and plant height can be assigned
to chromosome positions. Chromosome location information,
in turn, provides tools for physiology, developmental genetics,
and finer structure genetic analysis. We hope that this
networking will also lead to longer-term partnerships.
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