|How are organic seedless grapes possible? Which is
to say how can you have seedless grapes without
|Question Date: 2017-08-28|
Plants are very different from animals, especially
in terms of how they reproduce. Typically we think
of a plant growing from a fertilized seed;
however, some plants can also be propagated
(made to grow) through cuttings (i.e. taking
some part of the plant and replanting it directly
into the ground!).
Genetically modified seedless grapes are
easy to imagine; a scientist knows which genes to
alter to prevent the plant from making seeds, and
propagates it through cuttings, essentially making
clones of the original plant.
However, we know that seedless varieties of
certain fruits existed long before genetic
modification was possible! It's a much rarer
phenomenon, but all organisms have a low level
of random mutations, some of which can lead to
interesting phenotypes like a lack of
seeds. Mutant plants lacking seeds obviously can't
reproduce on their own, but our ancestors must
have discovered these mutants and propagated them
using the same technique.
In other words, generating a fruit or vegetable
with a very specific desired trait without genetic
modification takes a lot of time and luck!
That depends on what you call "genetic
Seedless grapes are mutants - they were
created when something altered the grapes' DNA to
cause them not to produce seeds. The cause of
this mutation was probably natural; it may have
been ultraviolet light from the sun, a
naturally-occurring poison in the soil, or just an
error in the cells' proteins in copying their DNA.
Whatever the cause, human growers saw this, and
then began cultivating the seedless grapes. This
is called "artificial selection".
Humans have been doing this for many
thousands of years, and is how all of our
domesticated animals and plants (including grapes)
Technically, artificial selection depends on
genetic modification, but it can make do with
natural genetic modifications like mutations.
The fear of genetic modification that causes it
to be banned from organic food is a fear of
artificial genetic modification, i.e. intentional
mutants, instead of naturally-occurring
mutants. Organic growers can (and, indeed, must)
use mutants that have occurred naturally, since
natural mutation is the source of all
differences between different living things
(for example, the difference between you, a human
being, and a grape vine, all amounts to about a
billion years' worth of natural mutations,
filtered by the gauntlet of natural selection).
Seedless grapes were genetically modified, very
very slowly. People selected the grapes with
the fewest seeds to grow, for many generations of
grapes. Now the seedless grapes are grown from
cuttings of the grape vine that are planted
and grow roots. It's not called 'genetic
modification,' because it happened so slowly and
so long ago.
Here's an article:
This is a very interesting question because it
begs the question, “what exactly is genetic
Currently, when we talk about genetic
modification we typically mean adding or removing
a gene from an organism. This could definitely
be used to create seedless grapes: just remove the
gene or genes responsible for seed creation and
you would have seedless grapes. But humans have
been creating seedless fruits for much longer than
gene altering technologies like CRISPER have been
around. By specifically breeding plants that have
small seeds together, you can create a new
generation of plants that all have small seeds.
From there you pick the offspring plants with the
smallest seeds and breed them together. If you
continue this trend for multiple generations
eventually the seeds won’t grow at all. You’ve
created seedless grapes!
You haven’t gone directly into the genome and
removed the gene or genes for seeds but, in a
sense, you have modified the genetics of the
grapes. You’ve artificially selected certain
traits and designed an ideal grape. But don’t
worry, humans have been doing this for years
whether it’s creating sweeter fruits or selecting
for dog breeds. The selective breeding process
is humanity’s first attempt at “genetic
modification” and it has occurred long before
we even understood what we were doing. Thank you
for the question!
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