Epigenetics and Clones
The high-goal season this year has shown that
the Polo Argentino breed is a pioneer in clone
production at a global level. However, from my
position as geneticist, I would like to comment
on this type of animals and their relation to
epigenetics.
When we refer to horses being “genetically
identical”, what we mean is that their genome—
that is to say, their nucleotide sequence—is exactly
the same as the founder horse and all its clones.
However, the epigenetic marks that we spoke of in
this article could be quite different between each
of the cloned individuals of one same founder.
This occurs because the cloning technique
uses NON-sexual cells (skin, fibroblasts, etc.)
as a mold to obtain the DNA of the animal to be
cloned, and these have very different epigenetic
marks. If we add to this the maternal effects of the
receptor mare in which the clone gestates, which
has no relation whatever with the founder animal,
and the environmental effects when it is raised,
we shall have a fairly complete explanation of
these small differences observed this year in the
Triple Crown. However, and as we said before, the
real effect of epigenetics on cloned animals still
remains to be seen.
To conclude, epigenetics is a science that is in
constant development and enables us to better
understand the whys and wherefores of some
situations which traditional genetics cannot explain.
These new technologies and new knowledge may
help us improve breeding practices in relation to
our horses, helping us focus on small details that
we did not take into account before.
Sebastián Demyda Peyrás
Veterinary Genetics Research Seat at the National
University of La Plata’s School of Veterinary Sciences
and of “Ing. Fernando N. Dulout”, Veterinary Genetics
Institute which belongs to the National Council of
Scientific and Technical Research (CONICET).
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