This eventually led to our development
of intragenic vector systems, which
involve identifying functional equiva-
lents of vector components from plant
genomes and using these DNA
sequences to assemble vectors for plant
transformation.Gene transfer using intragenic vectors
allows the well-defined genetic improve-
ment of plants without the introduction
of foreign DNA. Biologically, the
resulting plants are not transgenic,
although the tools of molecular biology
and plant transformation have been
used in their development. The genetic
make-up of the resulting plants is
equivalent to a minor rearrangement of
the endogenous DNA sequences within
the species. This is very similar to
“micro-translocations” that can occur
naturally in plant genomes or as a conse-
quence of deliberate mutation breeding.
For the transfer of genes from within
the gene pools of crops, intragenic
vectors may help to alleviate some of
the public concerns over the deployment
of GM crops in agriculture, especially
ethical issues associated with the trans-
fer of DNA sequences across wide taxo-
nomic boundaries. Nowadays, my
research is moving toward functional
genomics of potato to better understand
how important traits are controlled by
specific genes and their alleles. Ienvisage this will lead to valuable
sources of gene sequences for transfer
to existing elite potato cultivars via intra-
genic vectors.Early in my career I never considered
it would be possible, in my lifetime,
for science to generate the full genome
sequence of a higher organism.
Yet, within the next 5–10 years the
annotated sequence, at least for the
gene-rich regions, of the genomes of
all major crops will be known. This
will provide unprecedented opportu-
nities for mining the germplasm collec-
tions of plant breeders for novel alleles
that represent variant versions of genes
with altered functions. The resulting
novel DNA sequences can then be
used for highly targeted genetic
changes in crop plants by transformation
of elite crop cultivars.The next few decades are going to be
exceptionally exciting for plant genetics
as research moves toward the targeted
design and development of genetically
enhanced plants for sustainable pro-
duction of high quality and healthy
food. My career has been an exciting
and fulfilling journey so far. But I
often think: “what if I was thirty years
younger?” What a tremendous career
opportunity modern plant genetics
would offer.References
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156 MOLECULAR GENETICS OF GENE EXPRESSION