Analyzing Kara and her Kittens

Love and Hisses is a blog I have been following for a long time – written by Robyn Anderson, who fosters cats and kittens in Alabama.  I’m not sure  exactly when I started reading the blog regularly, but it might well have been with Kara and her litter of kittens. In the end, the kittens were adopted out and Kara was kept on permanently.

 I thought it would be interesting to look at her and the kittens to see how her and the father cat’s genetics interacted to produce the kittens. All the pictures are from her blog and from her Flickr site and are used with her permission.

To the right is a more or less  undignified picture of Kara, still pregnant.  She is a pretty normal tabby without a lot of exotic features, as are the kittens.  So a lot of the more boutique genes (like wideband or inhibitor) are normal. This will shorten the tables by about half and the text significantly as well.

Kara is a typical “brown tabby”.  She has the normal Black gene, as shown by the color of her tabby stripes. She shows no sign of any Orange, so she is not a tortie or calico  – both of her Orange genes are ‘no Orange’. If she had a mixed Oo pair the odds would be very high that it would be expressed somewhere on her coat.

To find out what her Tabby gene is, we need a better angle…

The vertical thin stripes show that she has the mackerel tabby pattern.  To display mackerel, she must not have the T[a] dominant ‘ticked tabby’ gene at all.  She could be masking a classic tabby gene.

This also means that she has at least one Agouti gene to keep the tabby pattern from being hidden.  The brownish background color is due to high ‘rufousing’ factors, but is not controlled by a single gene.

The other modifiers are quickly run through – she is short-haired, not dilute, and has no white spotting. In fact, she doesn’t even seem to have any buttons or lockets.  The whitish chin is part of the standard tabby pattern.

Kara’s Genes

Locus	Genes	Notes
Black	B/-	“Black”
Orange	o/o	No Orange
Tabby	T/-	Mackerel Tabby
Agouti	A/a	Agouti – masking non Agouti
Dilute	D/-	No Dilution
Long Hair	L/-	Short Hair
White Spotting	s/s	No white spotting

Kaylee

Well, here’s a kitten that doesn’t resemble Mama.  The first thing that jumps out is the Orange.  Since this could not have come from Mama, then we know that the father cat was Orange.  The black and orange regions are solid, not striped.  This means that she has the non-Agouti factor expressed. Since this is recessive, Kara must have donated one, and the father the other.

The white paws, chest, and face show that the White spotting gene is present.  This also must have come from the father, since Kara herself has no White Spotting.  So at this point we know he is Orange with white. Remember, since Orange is a sex based gene, the male only has one color gene to donate to a kitten.

Kaylee’s Genes

Locus	Genes	Notes
Black	B/-	“Black”
Orange	O/o	Part Orange
Tabby	T?/-	probably Mackerel Tabby
Agouti	a/a	non Agouti
Dilute	D/-	No Dilution
Long Hair	L/-	Short Hair
White Spotting	S/s	White spotting (about L2-3)

Zoe

Zoe, another female, also shows orange patches with white. However, the black patches in particular show tabby stripes – often called a ‘calitabby’.  This means that unlike Kaylee, Zoe has the Agouti hair working. Note that the stripes run right over the orange/black patch boundary undisturbed.  The pigment maker and the tabby pattern maker don’t interact at all.

The white paws, chest, and stomach show that the White spotting gene is present. This also must have come from the father – which we knew already.

The only genetic difference between Kaylee and Zoe is the Agouti gene.  Quite a different look for one genetic change.

Zoe’s Genes

Locus	Genes	Notes
Black	B/-	“Black”
Orange	O/o	Part Orange
Tabby	T/-	Mackerel Tabby
Agouti	A/-	Agouti
Dilute	D/-	No Dilution
Long Hair	L/-	Short Hair
White Spotting	S/s	White spotting (about L2-3)

Inara

Inara is the third girl kitten, is also a calitabby. Genetically she is the same as Zoe, but the random choice of which parts of the embryo select the Orange active gene as part of ‘X inactivation’ and display as orange versus those that select the other and show as black gives her a different pattern.

The father’s White Spotting gene is also showing. In fact, with all four kittens showing white spotting, the odds are about 95 percent that he has two White Spotting Genes. With two genes he probably would be considerably whiter than the kittens.

Inara’s Genes

Locus	Genes	Notes
Black	B/-	“Black”
Orange	O/o	Part Orange
Tabby	T/-	Mackerel Tabby
Agouti	A/-	Agouti
Dilute	D/-	No Dilution
Long Hair	L/-	Short Hair
White Spotting	S/s	White spotting (about L2-3)

River

River was originally also thought to be a girl kitten, but was later found to be male.  One thing that genetics could tell you is that River, if a girl, could not have the same father as the other kittens.

We already know that the father has an Orange gene to donate to a daughter, and no other. So for a female kitten to be all black, all the cells would have to have chosen “No Orange”.  This seems unlikely.

The alternative is that River was a girl with a different father, or that River is male, and thus the father donates the Y sex gene rather than Orange. This leaves Kara’s gene to determine the color.  To sum up, in male kittens the Orange color gene comes only from the mother.  And indeed, it turned out that River was male after all.

I know it is possible for a litter of kittens to have different fathers. I don’t know how common it is.

Even though this picture doesn’t show it, River also shows the white spotting, slightly less than his sisters do

River’s Genes

Locus	Genes	Notes
Black	B/-	“Black”
Orange	o/y	no Orange
Tabby	T/-	Mackerel Tabby
Agouti	A/-	Agouti
Dilute	D/-	No Dilution
Long Hair	L/-	Short Hair
White Spotting	S/s	White spotting (about L2-3)

Daddy Cat

So what do we know about the father? We know he had quite a lot of white spotting, and otherwise was orange.  He could have been dilute, and been creme rather than orange, but most likely not.

He needed to have at least one non-Agouti gene for Kaylee.  If his other one was also non-Agouti, then half his kittens with Kara would show it. Otherwise, only a quarter would. Only one of four did show it, but the odds aren’t large enough to call it either way.

He probably doesn’t carry the ticked tabby version of the Tabby gene. If he had one of these dominant genes, half his kittens would show it. If he had two, all of them would.  He could have had one or more recessive Classic Tabby genes.  These would never show if Kara had two Mackerel genes.

The picture is of Spanky, one of Robyn’s permanent resident cats, who might look very much like the father of the kittens.  I don’t think he had the chance to be the actual father.

Daddy Cat’s Genes

Locus	Genes	Notes
Black	?	unknown, masked
Orange	O/y	Orange
Tabby	?	not ticked tabby
Agouti	?/a	at least one non-Agouti
Dilute	?	probably No Dilution
Long Hair	L?/-	probably Short Hair
White Spotting	S/S	significant White spotting

I’d like to thank Love and Hisses for all the years of kitten pictures and stories, and for the Hisses-o-lanche of last weekend to boot.  Reading her blog is the next best thing to having bunches of kittens of your own – no petting, but you don’t have to clean up the messes either!