Easy Lop Color
Genetics
by Kim
Powell
Written according to the Lop Color Guide, specifically for French and English Lops.
I
am going to write this article so anyone at all can
understand
it. In fact there are only two new words you will
have to
know to understand color genetics in Lops (I am only going
to
cover varieties that are accepted in the Lops). They
are:
Dominant: needs only one gene to be expressed and
will cover
up any gene less dominant; is shown with capital
letters.
Recessive: Needs two genes to be expressed; is
shown with
lower case letters. The other thing you should be
aware
of is that fact that a rabbit will inherit one gene (or half
of
each pair) from each parent. Lastly, when "_"
is
placed after a gene, it merely means that we do not know the
gene
(and it doesn't have an affect on the rabbit's
color).
The
first set genes you will need to know about is the A
series.
This gene series does not determine color, rather it
will determine
what pattern your rabbit is: Agouti (three to five
rings of color,
white belly color) or Non-Agouti (or self).
Agouti is the
dominant of the two and is represented by A.
Non-agouti
is recessive and is represented by the letter
a.
AA
Agouti
Aa
Agouti
aa
Non-Agouti (or self)
So a rabbit needs only one Agouti gene
to have an Agouti pattern,
but it needs two recessive Non-Agouti
genes not to show the Agouti
pattern. If you have an Agouti
born in the litter, at least
one parent MUST be an
Agouti. On the other hand, if
you have a rabbit without the
Agouti pattern born out of two Agouti
parents, that must mean that
both the dam and sire are hiding
the recessive Non-Agouti
gene.
The
rest of the genes we will discuss actually determine the color
of
your rabbit. The first of these is the B series.
Black is
dominant and is represented by B, while Chocolate is
recessive and
represented by
b.
B
Black
Bb
-
Black
bb
Chocolate
This is not to say that all rabbits are either
Black or Chocolate,
rather that they must carry the genes for one of
these pigments,
and the interaction of later gene series change the
color (by
restricting or eliminating pigment, diluting
color).
The
C series contains 5 genes, but only 4 of these affect our
Lops (as
Pointed Whites are not accepted). Each of the genes
in the C
series is dominant to the genes listed below it.
C (Full Color)
is dominant to all genes, while c (albino) is completely
recessive to
all other genes in the C
series.
C
allows color development of all black and yellow
pigments
c(chd)
chinchilla turns yellow pigments to white or
pearl
white
c(chl)
shading gene. Commonly referred to as the
"light
chinchilla gene," it is not in fact a chinchilla
gene at
all. Eliminates all of the yellow pigments and turns
black
into sepia brown. Eyes will have a ruby
cast.
c
albino gene. Prevents the development of any
pigment,
regardless of any other genes that may be
present.
C
(Full Color) is dominant to all the genes listed below it.
If
you rabbit has one C gene, regardless of whether it also carries
the
shading gene or the albino gene, it will show Full
Color
pigment in the fur. If your rabbit carries one
c(chl)
gene and one albino gene (we would write this as
"c(chl)c",
your rabbit will be a shaded variety. The
albino gene is
the most recessive. Many times, people will have
REW's pop
up in litters when there are no REW's visible on the
pedigree.
This tells us that both the dam and the sire carry
the recessive
c gene. A REW is simply a colored rabbit hiding
beneath
a white sheet. The albino gene prevents us from seeing
whether
the rabbit may be a Steel, a Self, a Dilute because it
prevents
the development of all
pigments.
The
D Series also affects the coat color. D (Dense Color)
is the
dominant gene, and d (dilute) is the
recessive.
D
Dense Color. Rabbits will have brown
eyes.
d
Dilute Color. Often described as appearing
"silvery,"
rabbits will have blue or blue-gray
eyes.
So
a rabbit may carry the dilute gene, and not show it.
This would
look like this "Dd." For a rabbit to
be a dilute
color ("dd"), it must inherit one Dilute
gene from each
parents. Whether or not the parents themselves
are dilute
colors, it doesn't matter. When a dilute color
pops up in a
litter, each parent must carry the dilute gene: Dam
= "Dd",
Sire = "Dd." Or one parent may
be a Dilute, while the
other parent merely carries the gene:
Dam or Sire =
"dd" the other parent = "Dd."
Each
Dense Color has a Dilute counterpart. For example,
Blue is the
Dilute of Black, Lilac is the Dilute of Chocolate.
Here are a
few
others:
Dense
Color
Dilute
Color
Chestnut
Opal
Black
Chinchilla
Blue
Chinchilla (or Squirrel)
Black
Tort
Blue
Tort
The
last series we will talk about that controls color is the
E
series. These genes control the black pigment. The
genes
here are little more tricky because here we have our Steel
gene, or
Es. The steel gene is the only dominant gene that
can be
hidden. The genes in this series
are:
Es
Steel. Produces an over abundance of dark
pigment.
Covers up the intermediate band in agoutis, and covers
the normal
agouti markings (including the belly). Belly color
on steels
is
gray.
E
Normal Extension of the black pigment. Most rabbits
are
EE. Agoutis will show normal ring
color.
ej
brindling gene
(Harlequin).
e
non-extension gene. Removes all or most of the
black
pigment in the coat. In agouti rabbits, all the dark
pigment
I removed. In self rabbits, some shading is still seen
around
the nose, tails and
feet.
The
steel gene is so common in French Lops, but it one that not
too many
breeders really understand how it works. The steel
gene also
needs an Agouti gene, A, to do its job properly.
When a rabbit
inherits two Non- Agouti genes, aa, and a Steel
gene, Es_, the result
is a "self-steel." Mostly
these rabbits will have
white hairs scattered throughout.
This is why we say the Steel
gene, a dominant gene, can be covered
up. When a rabbit is
"Ese," the Steel gene can
not fully express itself, and may
be covered up. Sometimes
a rabbit will inherit two Steel genes,
EsEs. Two Steel genes
remove more dark pigment, and will
usually leve you with an almost
black rabbit, or one that just has
light ticking over the
entire
body.
The
E gene is what most rabbits carry. The is just the
normal
color. Blacks, blues, chestnuts and opals are all
"EE"
or maybe even
"Ee."
The
Non-Extension gene, or e, is what removes dark pigment from
the
coat. Our reds, oranges and fawns all carry two of these
genes,
along with an agouti gene. If a rabbit carries a
self gene, and
"ee," it will become a tort variety or
a sable point.
For
example:
Black
Self with
"ee"
=
Black
Tort
Blue
Self with
"ee"
=
Blue
Tort
Siamese
Sable with "ee"
=
Sable
Point
Notice
that I haven't said anything about the ej gene or
Tri-color
varieties, which the Lop Standard does accept. As of
now,
there are very few breeders breeding this gene into their
Lops,
and as it is a very confusing gene, it would merit a whole
article
by
itself.
The
last gene we will discuss is the Broken gene, En. This
one is
very simple. There are two genes in our Lops, En
(Broken) and
en
(solid).
Enen
= Broken
Pattern
enen
= Solid
Pattern
EnEn
= Charlie
Pattern
A
normal Broken rabbit with a good color Pattern will have one
of each
gene. When two brokens are bred together, Charlies
may be
produced.
Broken (Enen) x Broken (Enen) =
25%
Solid
50% Broken
25% Charlies
A Charlie inherits one
Broken gene from each parent and is very
lightly marked. Most
will have a little color on the nose,
on the ears and a thin strip
going down the back. Most Charlies
are not showable as they
will not have the required 10% color,
but can be used for
breeding. When a Charlie is bred to
a Solid colored rabbit, all
Broken rabbits will be
produced.
Charlie
(EnEn) x Solid (enen)
=
100%
Broken (Enen)