~~~☆Tetsuwan Atomu!☆ベンニ's Genetics Training~~~

I am glad that you are enthusiastic about learning genetics! :) At times you may have trouble understanding what I am talking about and that is normal. But PLEASE tell me when you are having trouble because it will only get more confusing if you keep going without asking questions.

With that in mind though, this is going to be fun. :)

Okay, so here is my guide about genetics. If you are ever stuck you can refer to this to see if that helps.

https://docs.google.com/file/d…WxReEIyLU56V0E/edit?pli=1

So first things first. Skin color is controlled by pigments called Melanin. Everything has it. Melanin protects your skin from the sun.
"Melanin: The pigment that gives human skin, hair, and eyes their color. Dark-skinned people have more melanin in their skin than light-skinned people have. Melanin is produced by cells called melanocytes."

There are two different types of melanin cells in cats. Eumelanin and Pheomelanin. Eumelanin is the normal type and Pheomelanin is the mutated type.

Eumelanin is what makes a cat look black, chocolate, or cinnamon. When the cat has the mutated version called Pheomelanin, the cat loses the ability to produce melanin and the cat ends up looking red/orange.

So we are first going to focus on Eumelanin colors because those are the easiest to start with.

Genotypes:

Eumelanin-based pigments: (B, b, bl)
Black is produced when the cat has at least one "B" gene.
Chocolate is produced when the cat lacks the "B" gene and has at least one "b" gene.
Cinnamon is produced when the cat lacks both the "B" and the "b" gene and has two "bl" genes.
These pigments are just black with reduced intensity.

A black cat would be "BB, Bb, or Bbl" (If the cat is not carrying anything it would be "BB")
A chocolate cat would be "bb, or bbl" (If the cat is not carrying anything it would be "bb") - (chocolate can never have a "B" because chocolate is recessive to black)
A cinnamon cat can ONLY be "blbl" (this is because cinnamon is recessive to both chocolate and black)

I want you to guess the genetic code for the following cats:

Black Cat:
Chocolate Cat:
Cinnamon Cat:

☆Tetsuwan Atomu!☆ベンニ wrote:

awesome! I'm really excited to learn, and thanks so much for taking the time to teach me what you know! I'll definitely ask questions when and where I have any! ♡

I'm familiar with the basics for some genes being recessive and some being dominant, so this first stuff will be easy~ im also familiar with punnett squares, too, if those come into play!

Black Cat: BB, Bb, Bbl
Chocolate Cat: bbl, bb
Cinnamon Cat: blbl

Perfect! I am glad because I forgot to ask you if you had learned about Mendel and about dominant and recessive traits. Some of this may be review but that is okay. :) I will put key words in bold.

For each set of genetic traits, a cat will get two alleles. One from the mother and one from the father.

In this case, we have 3 different alleles that code for normal coat color. This trait is often referred to as the cat's Base Color. So if you see anyone talking about the Base Color of a cat, they are referring to the Eumelanin colors.

So from looking at which alleles code for black, chocolate, and cinnamon, you should be able to see which allele is the most dominant and which allele is the most recessive.

Now when a cat has two of the same allele (ex: BB) the cat is said to be homozygous for that trait. And when a cat has two different alleles (ex: Bb) the cat is said to be heterozygous for that trait.

Each set of traits has two different ways of describing it. The phenotype and the genotype.

Phenotype refers to the the physical description of that allele.
Genotype refers to the genetic description of that allele.

For Base Color, the phenotype refers to the colors (black, chocolate, and cinnammon), and the genotype refers to the allele combination (ex: BB, bb, blbl).

To figure out what color the kittens will be when you cross two Eumelanin colored cats, you set up a punnet square using the genotypes of the parents. :)
Click Here for a Punnet Square reference PDF

For now we are going to assume that these cats are homozygous for Base Color. Since the base color isn't gender specific, it doesn't matter which is the male and which is the female, but I will let you know which is which.

So if we were going to do a cross of a male Black cat and a female Black cat, the punnet square would look like this:

B B

B BB BB

B BB BB

What does this mean? This means that when crossing two black cats that are both Homozygous for that trait, the phenotype of all of their offspring will be Black.

So if I were to write this out it would look like this:

Black x Black

Black

So when you do pairings, you will write out your answers like this: (replacing the male, female, and offspring with colors of course) When you are doing pairings for other people you don't have to write out the punnet square, but for practice I want you to write it out.

Male x Female

Offspring

Review Questions:

1) What does it mean for a trait to be dominant? recessive?

2) For base color, write out the colors (not alleles) in order of most dominant to recessive.

3) Based on the Genotypes, can you name the Phenotypes of the following cats?

BB =

blbl =

bbl =

4) Figure out the offspring of these cat pairings: (for these problems, assume that the parents are homozygous for their colors)

Black male, Black female:

Chocolate male, Black female:

5) Figure out the offspring for these cat pairings: (for these problems, assume that the dominant colored parent is heterozygous for the color of the recessive colored parent)

Cinnamon male, Chocolate female:

Black male, Cinnamon female:

**Make sure you follow the template that I used in the example above.**

☆Tetsuwan Atomu!☆ベンニ wrote:

1) What does it mean for a trait to be dominant? recessive?
A dominant trait allele is the one that will show in the phenotype; ex. Bbl, B is dominant because the cat will show to be B, or black, physically. bl is recessive, because it does not show physically, but it can be passed on to offspring.

2) For base color, write out the colors (not alleles) in order of most dominant to recessive.
Black
Chocolate
Cinnamon

3) Based on the Genotypes, can you name the Phenotypes of the following cats?

BB = Black

blbl = Cinnamon

bbl = Chocolate

4) Figure out the offspring of these cat pairings: (for these problems, assume that the parents are homozygous for their colors)

Black male, Black female:

all Black offspring, homozygous

Chocolate male, Black female:

All Black phenotype offspring, heterozygous with one Black genotype and one Chocolate genotype per cat.

5) Figure out the offspring for these cat pairings: (for these problems, assume that the dominant colored parent is heterozygous for the color of the recessive colored parent)

Cinnamon male, Chocolate female:
One heterozygous chocolate offspring, three homozygous Cinnamon offspring.

Black male, Cinnamon female:
One heterozygous black offspring, three homozygous Cinnamon offspring.

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Questions 1-4 are correct. Question 5 is incorrect. For future reference, I want you to type out the question as I did in the example.

I want you to re-write it out and put this in your answer because this is how you will do pairings when someone asks for genetics help. Often the person will say something like "What will the offspring be between my male Black cat and my female Chocolate cat" or something like that. And when you tell them their kitten possibilities this is how you will write it.

Black x Chocolate

Black, Chocolate

When doing pairings you wont need to type out the punnet squares but for the sake of practice and learning I want you to also include the punnet squares in your answers so I can see your work.

Male
B b
Female b Bb bb

b Bb bb

This way you can see that you will get homozygous chocolate kittens as well as heterozygous black kittens.

And remember, when listing out the kitten possibilities, you only need to list out the phenotype possibilities, you don't need to include homozygous and heterozygous because those are the genotypes.

So even though you got question 4 correct, I want you to re-do both questions 4 and 5. And do it in that format.

☆Tetsuwan Atomu!☆ベンニ wrote:

understood. thanks for the clarification! ♡

4) Figure out the offspring of these cat pairings: (for these problems, assume that the parents are homozygous for their colors)

Black male, Black female:

B. B.
B. BB. BB

B. BB. BB

Black x Black
Black

Chocolate male, Black female:
B. B
b. Bb. Bb

b. Bb. Bb

Chocolate x Black
Black

5) Figure out the offspring for these cat pairings: (for these problems, assume that the dominant colored parent is heterozygous for the color of the recessive colored parent)

Cinnamon male, Chocolate female:

b. bl

bl. bbl. blbl

bl. bbl. blbl

Cinnamon x Chocolate
Chocolate, Cinnamon

Black male, Cinnamon female:

B. bl

bl. Bbl. blbl

bl. Bbl. blbl

Black x Cinnamon
Black, Cinnamon

How's that?

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Perfect!!!

Do you feel comfortable with these base colors? Because next we are going to talk about dilutes and tabbies.

Awesome!

So you already know how the 3 Eumelanin Base Colors are Black, Chocolate, and Cinnamon. And that the Base Color genes are B, b, and bl.

Next we are going to learn about a set of genes that alter the Base Color called Dilute but first we need to know how the Eumelanin pigments work.

Each pigment (black, chocolate, and cinnamon) is a slightly different shape, and this shape difference is what gives you the different color. Those pigments are compacted into each strand of hair.

The dilute gene alters this by spreading apart those pigments which causes the cat to appear lighter (and therefore diluted).

Ignore the middle (Caramelized versions) for now because we will learn about those later but these graphics are a pretty decent visualization of what I am describing.

So as you can see, the diluted versions are as follows:

Dense --> Dilute
Black --> Blue
Chocolate --> Lilac
Cinnamon --> Fawn

The dilute alleles are represented by "D" and "d". Dense (D) is dominant over Dilute (d).

Now when we write out the genotype of cats we will also be including the dense/dilute alleles as well. So each cat will now be written with 2 pairs of alleles.

Example:

Black = BB DD

I want you to guess the genotypes for the following phenotypes:

Chocolate =

Fawn =

Blue =

Black =

Now guess what the phenotype is based on these genotypes:

Bb dd =

bb dd =

blbl Dd =

bbl dd =

☆Tetsuwan Atomu!☆ベンニ wrote:

understood!

Chocolate = bb, DD

Fawn = blbl, dd

Blue = BB, dd

Black = BB, DD

Now guess what the phenotype is based on these genotypes:

Bb dd = Blue

bb dd = Lilac

blbl Dd = Cinnamon

bbl dd = Fawn

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Everything is correct except that last one. Easy mistake because it was right after the Cinnamon genotype. You clearly have an understanding of the genotypes, so I am not too worried that you wrote Fawn instead of Lilac again since you probably just assumed that I wrote a typo. I was just testing ya. :P

So now we have two punnet squares to do. Now in the genetics test you will need to assume that unless there is a dilute parent, that both parents are homozygous for dense. And that is how we are going to learn it. Just know that when you are doing pairings for people, you will always assume that a dense colored cat is heterozygous for the gene. That way they can get more variety of kittens.

BUT in this thread, a dense cat will ALWAYS be homozygous for dense unless there is a dilute parent, in which case the dense parent will be Heterozygous for the gene.

Example:

Black x Chocolate

Black, Chocolate

B b D D

b Bb bb D DD DD

b Bb bb D DD DD

Try these pairings:

Black male, lilac female:

Fawn male, blue female:

Cinnamon male, chocolate female:

Blue male, Black female:

☆Tetsuwan Atomu!☆ベンニ wrote:

ah, yeah, I thought it said blbl dd, I didnt notice it was actually bbl dd! reading mistake! ♡

Black male, lilac female:
Assuming the black is heterozygous;
B. b. D. d
b. Bb. bb. d. Dd. dd

b. Bb. bb. d. Dd. dd

Black x Lilac
Black, Chocolate, Blue, Lilac

Fawn male, blue female:
B. bl. d. d
bl. Bbl. blbl. d. dd. dd

bl. Bbl. blbl d. dd. dd

Fawn x Blue
Blue, Fawn

Cinnamon male, chocolate female:
b. bl. D D
bl. bbl. blbl. D. DD. DD

bl. bbl. blbl. D. DD. DD

Cinnamon x Chocolate
Cinnamon, Chocolate

Blue male, Black female:
B. B. D. d
B BB. BB. d. Dd. dd

B. BB. BB. d. Dd. dd

Black x Blue
Black, Blue

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PERFECT!

Dilute colors are pretty easy. :) I will type up the tabby lesson after work today. :)

Okay, so next we will be talking about Tabbies. The tabby gene is referred to as the "Agouti" gene.

Agouti actually refers to the banding pattern of the hair. There are two different types of hair on tabbies. The Solid hairs are what produce the actual tabby markings, and the Agouti banding hairs are the "background" hairs. The Solid hairs show what color the cat actually is. So a cat with black tabby stripes is a Black Tabby (However, black tabbies are called Brown Tabbies - not to be confused with Chocolate Tabbies, which are have the "b" gene and are Chocolate colored Tabbies).

The neat thing about these agouti banding is that the stripes alternate between Pheomelanin and Eumelanin pigments. (As seen in the picture photo below).

Here is a closeup of the Agouti hairs on a Brown Tabby.

[img width=510 height=337]http://img.photobucket.com/alb…my%20kitties/Malibuah.jpg[/img]

The normal coloration of cats is to be Tabby. The solid gene is actually a mutation that blocks the production of these Agouti bands.

What this means is that the tabby banding is actually still there. Even though you cannot see it in Adult solid cats, you can actually get a glimpse of what tabby markings kittens would have if they didn't have the mutated copy of the Agouti gene (which made them solid).

[img width=510 height=429]http://www.pets4homes.co.uk/im…kittens-5241b697a9df1.JPG[/img]

This tends to go away when they get older (not sure of the mechanics of why you can see the markings sometimes). BUT there are breeds that take advantage of this and have bred their cats to maintain the ghost markings. You can see this in Egyptain Maus.

Anyway, so the genotype of Agouti is "AA or Aa" and the genotype for solid is "aa" and Agouti is Dominant over Solid.

Agouti = AA or Aa
Solid = aa

There are 4 different tabby patterns (3 of them are on separate loci - this means that they are seperate genotypes and are completely independent of each other).

[img width=510 height=153]http://home.earthlink.net/~per…rpictures/tabbytypes1.jpg[/img]

Classic and Mackerel are on the same locus. Mackerel Tabby is dominant over Classic Tabby. Mackerel Tabbies have thin stripes, and Classic Tabbies have thick stripes that swirl into a bulls-eye pattern.

Mackerel Tabby = McMc or Mcmc
Classic Tabby = mcmc

Spotted Tabby is on a serarate locus and affects the Mackerel/Classic tabby pattern by chopping up the pattern into spots. Mackerel Spotted Tabbies tend to have smaller spots than Classic Spotted Tabbies. This is not important for predicting litters here on Feral Front because people tend to not care or understand this so we just don't complicate it too much. However, I think it is really neat so I am teaching it to you anyway. Just know that when doing litters, you won't distinguish between Mackerel or Classic Spotted Tabbies. You will just refer them all as Spotted Tabbies.

Since Spotted Tabby modifies the Mackerel/Classic Tabby markings, it is dominant over them. It is a gene that is either "ON" or "OFF".

Spotted Tabby = SpSp or Spsp
Normal Tabby = spsp

Ticked Tabby is on a separate locus as well and also affects all tabby markings by blocking the production of tabby stripes. This gene only allows the agouti banding to be produced (except on the head - there is still the signature "M" marking that the tabby stripes produce).

Since ticked tabby stops all production of the tabby stripes, this means it is dominant over all other tabby markings. This pattern is also an "ON" or "OFF" gene.

Ticked Tabby = TaTa or Tata
Normal Tabby = tata

HOWEVER, when the cat is heterocygous for Ticked Tabby (Tata) there can sometimes be banding produced on the legs. This is not important for predicting litters but is still cool. With litters you will not distinguish between banding on the legs or not. They will all just be referred to as Ticked Tabbies.

SO lets Recap:

Agouti = AA or Aa
Solid = aa

Mackerel Tabby = McMc or Mcmc
Classic Tabby = mcmc

Spotted Tabby = SpSp or Spsp
Not Spotted = spsp

Ticked Tabby = TaTa or Tata
Not Ticked = tata

Ticked > Spotted > Mackerel > Classic

1) Guess the phenotypes of the cats below: (Remember, Black "Pattern" Tabby = Brown "Pattern" Tabby, All other tabbies will just be "Color" "Pattern" Tabby)

BB dd AA McMc spsp tata

bb Dd aa mcmc Spsp Tata

blbl dd Aa Mcmc spsp TaTa

BB Dd Aa mcmc spsp tata

bbl dd Aa mcmc Spsp tata

2) Predict the kittens: (These will just be generic tabby patterns - you don't have to do the pattern punnet squares. Just write "color" Tabby. Ignore the pattern for these ones)
~~Always assume the agouti gene is "Aa". This will be assumed on the test.
~~Always assume that solid colored cats would normally be Mackerel Tabbies (McMc spsp tata) if they had the agouti gene

Brown Tabby male, Blue female:

Chocolate male, Cinnamon Tabby female:

Fawn male, Blue Female:

Lilac Tabby male, Fawn Tabby female:

3) Predict the kittens: (Until you understand the tabby markings, do the punnet squares for all tabby markings. You may skip the punnet squares for base color and dilute if you feel you understand them)
~~Always assume the agouti gene is "Aa". This will be assumed on the test.
~~Always assume that solid colored cats would normally be Mackerel Tabbies (McMc spsp tata) if they had the agouti gene.
~~Always assume that spotted tabbies are Mackerel Spotted Tabbies (McMc Spsp tata)

Chocolate Classic Tabby male, Chocolate Mackerel Tabby female

Brown Ticked Tabby male, Black female

Blue Spotted Tabby male, Chocolate Mackerel Tabby

Cinnamon male, Fawn Classic Tabby

Two things really quick. Brown Tabby is the breeder name for Black Tabby. Brown Tabby isn't Chocolate Tabby.

Second I should have clarified how to write out Tabby litters.

Example:

Brown Tabby x Blue

Black, Blue, Brown Tabby, Blue Tabby

Chocolate Mackeral Tabby x Cinnamon Classic Tabby

Chocolate, Lilac, Cinnamon, Fawn, Chocolate Tabby, Lilac Tabby, Cinnamon Tabby, Fawn Tabby

Tabbies will be Mackeral or Classic.

Sorry. :)

Need help?

I hope you haven't given up. You have been online since you last posted but haven't responded on here yet.

Just letting you know that I think you have been doing really well so far. I guess just let me know if you ever decide to learn again. Until you respond I am going to assume you decided to stop learning genetics.