Page 52 - Koi Net - On-Line Koi Magazine - Issue 17
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big, one Koi can have a small mouth and fins, another other local preditors reside. Also selective breeding has
can be perfect. Or the difference is small, where only weakened their natural immune system, so although
the tint of the Hi looks different. This difference could they can live happily in ponds under our care, their
be explained by only a few different colour beads out of chances of survival in the wild would be limited. We
the millions in the DNA in the nucleus. select Koi for their beauty, nature selects Koi for their
strength and survival of the species.
The genetic code that is unique for each Koi is called
THE GENETIC the genotype. The phenotype is the result of this I explained DNA before. Well, egg cells and seed cells
genotype – all properties present at birth, plus all that
contain one of the DNA strains per Chromosome. Upon
CODE THAT IS happens and influences the Koi during its life. The merger these are connected, one from the male and
UNIQUE FOR phenotype is what we observe at this moment. As an one from the female per Chromosome. At that moment
it is decided what characteristics the seedling has. This
example, people can be born with brown hair, but
EACH KOI IS sometimes they bleach or dye it to produce the most is a combination of characteristics from both the male
and female which together make up the genotype for
amazing colours.
CALLED THE the new organism. The decision which characteristics
GENOTYPE NATURE HAS will be used is based on a system called dominant and
recessive genes. It is obvious that a mother’s DNA
FOUND A coded genes describes the hair colour, blonde for
instance, but the father’s DNA also encodes for a
WAY TO colour, brown for instance. One of them ‘wins’, and
COPE WITH you get the colour of the one that dominates, the
dominant one.
DIFFERENT The other gene is called recessive. This is not a dice
PROBLEMS game because it is pretty much fixed for every
combination what the dominant gene will be. When
later in life you have a child of your own, there is a
possibility that you pass either the blonde, or the brown
gene. This is just a game of chance, 50% chance for
either one. This will then again be combined with the
gene from your partner, and this again could be blonde,
brown, red or black, or otherwise depending on your
choice of partner. The dominant gene wins again in
With Koi this can be really noticeable when a Tancho
your child.
possesses a perfect heart shape Hi spot where it is
obvious that a part of the original Hi was removed. Just Now for something completely different. Nature has
like a seedling of the woman with the coloured hair will found a way to cope with different circumstances as
not have these colours in her hair at birth, the seedling species, like global warming. Just a wild example
of this Koi will not have a heart-shaped Hi spot. On the because that just isn’t real – Or is it? The process also
contrary, a large female Koi that has lost its looks, works this way in humans and animals, including Koi.
missing an eye, and part of a fin which have been lost When the egg and seed cells are made, sometimes
over time, can still produce perfect and beautiful Koi. small errors, changes in the DNA occur and remain.
That is genotype and phenotype. Sometimes this is one single coloured bead different
from the parent strain. This single change could result
Our Koi have been selectively bred to produce highly
in a Koi’s skin, for instance, instead of being green, to
prized colourful specimens, however, they would not
become a little bit more white. Now, if water was white,
survive in their original habitat where pike, heron or
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