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Back-crossing might
slow down the accumulation of genetic changes by
using "old" genes from previous
generations instead of using "new"
(possibly slightly changed) versions of those
genes. Sticking with "old" genes slows
down the rate of change. At worst, the gene pool
could stagnate, missing out on beneficial minor
mutations. At best, random harmful mutations might
be avoided and a type would be "fixed"
for longer. Unless cloning becomes the norm, there
is little danger of gene pool stagnation since
there will be far more cats reproducing in the
conventional manner. However, selective breeding
has already greatly reduced the gene pool of some
animals and breeds, in which case cloning and
breeding from clones will worsen the situation by
reducing genetic variation.
A breeder might want to perpetuate a mutation
but there is a limit to the number of females a
stud cat can mate with or to the number of kittens
a female cat can have. For example what if a
female gives birth and then contracts such a
serious uterine infection after giving birth that
she has to be spayed to save her life? Her genes
could be saved by creating a clone. What if a
potential cat had already been castrated by a
previous owner? Cloning will create an uncastrated
cat which can pass on its genes in the normal way.
Sometimes the desirable trait is rare so that
breeders want to increase the number of cats
carrying that trait . Cloning means that several
copies exist and can be used as foundation stock
in several breeding lines at the same time,
overcoming the physical limitation of having a
single cat. This will get a breed going much
quicker than with just one foundation stud.
Cloning and genetic engineering provides the
potential for designer cats.
Neutering and spaying will no longer be a dead
end. In one sense this could be a lifeline in
preserving a rare trait, but it also means that
pedigree cats sold with a neutering/no-breeding
agreement could be cloned to create a fertile
individual used by a backyard breeder.
The impact on pedigrees will be many and varied
and potentially serious. Although reputable
breeders will abide by registry regulations or
seek special dispensation for certain activities e.g.
cloning a genetically important stud cat killed in
a freak accident, there will be unscrupulous
individuals who will take advantage of the new
techniques, especially as the cost comes down.
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