Sunday, July 30, 2006

CAT GENOMICS




The above cat and kitten are not clones -- they arrived at the same template the old-fashioned way -- probably overriding the father’s genes with the potent calico XX formula. (This was a Sixties ‘free range cat -- I have no idea who the father was, but I’m betting that since it was a Browning cat -- a “rez cat” -- it was not wimpy.)

This is the only pair of near-identical cats I’ve had. The mother’s name was “Thumper” because when she traveled on a hard surface indoors, she put her feet down so hard that she sounded like a horse trotting. (Well, not QUITE, but you get the idea.) The kitten’s name was “Mama’s Little Baby,” for obvious reasons. She followed her mother around, sitting the same way, lying down the same way (except for nursing) and proceeding at the same rate. The other kittens went their own way.

When cats ARE cloned, it has disconcerted researchers to discover that they don’t get little duplicates of the mother! Not even the same color. Now it comes into focus that the negotiated relationship between maternal DNA and paternal DNA is not a simple zipper-like meshing after all. The cell itself has something to say about it, the biochemistry of the womb has input, and -- most important of all -- genes don’t just specify this characteristic or that (and REALLY they don’t say “blue eyes” or “brown eyes” but give the formula for the color in question), genes also say, “Okay, you’ve spent enough time on bone now -- begin to make muscle -- we’ll come back to bones later” (or some equivalent) and this time element introduces another variable. The color of the cat that is patched may be the result of the genes wavering: “make black fur -- no, orange.” No one has quite figured out the relationship between coat color in domestic cats and their other characteristics (vigor, predator skill, friendliness) but it seems likely that there is one.

Research into the feline genome is motivated in several different contexts. First, but much downplayed, is research on the biochemical physiology of cats and genetics, already much experimented on. Cats are better than rats for research on things like emotions (the autonomic nervous system) but many people are shocked by the process and would shut it down if they could, esp. the use of electrodes on brains.

Second is veterinary uses to safeguard the pets themselves but also to intercept whatever diseases might migrate to people, either directly (as many people think cat leukemia can) or indirectly (the cat that dragged in the rat that carried the flea that harbored the bacteria).

Third is the inquiry into the whole major category of cats which includes many charismatic mega-mammals like lions and tigers and panthers -- some of them endangered -- and a whole array of smaller spotted cats that never have been domesticated or, more likely, have never domesticated themselves. One project crosses domestic cats with a rather bigger spotted cat, producing burly, exotic-looking, sometimes-tame cats that people often crave to own.

Fourth is the cat fancy crowd, which is raising cats for profit and show and is interested in maintaining the health of the cats while not letting the characteristics of the breed escape. Some kinds of cat are greatly inbred, to the point of getting miscarriages, deformed kittens, diseases, and so on. One can get a little genetic "cheek swab" kit to send in one's own cat's genes.

Fifth is the forensic uses of cat DNA. In the famous "Snowball" case, a murderer was caught through the identification of cat hair -- more fun than carpet fibers.

My grandson, who stayed with us the summer of Thumper and Mama’s Little Baby (the summer he was six years old) asked me when he was grown up why I always had a calico cat and a yellow cat. Those were my favorite cat colors. I didn’t know why they were.

But one day I was reflecting on “attachment” and emotional patterning in individual children. (This is a whole category of clinical psychology, sometimes called “teddy bear psychology,” about how small children transfer their love of their mothers to their teddy bears as a way of becoming more independent.) It came to mind in a kind of vision that when I was small, my bed was pushed up against a bookcase and on the shelf level with my face, in front of the books, I kept a collection of tiny china figures that people had given me. (This was before plastics.) There was a penguin in a porkpie hat and muffler --not unlike Opus in the comics. I wonder if that cartoonist had a little china figure like that. His partner was a duck, unlike Daisy Duck except that she had long eyelashes. Also, there was a dog, maybe a spaniel, sleeping -- just a lump really, ears painted on.

But the figures I came back to over and over were a calico cat (only an inch or so tall) and a yellow striped cat, both with their tails staight up (a characteristic of domestic cats) and one front foot in the air. They had kittens, also with spike tails, no more than a half-inch tall. The littleness was important. I suppose they were about an inch-to-a-foot, the most common doll-house ratio and the proportion Bob Scriver used when making his dioramas. I played with them so much, marching them back and forth and talking for them, that they chipped and broke -- becoming a family of Manx cats.

Thus the pattern was formed for what I thought was “the right kind” of cat, just as I believed that our Scottie mix was the right kind of dog, but my father thought all dogs should be like “Coalie,” a black and white collie, HIS childhood dog. The postmaster and I were discussing potato salad recipes and she remarked, “Everyone thinks potato salad should be just like whatever his mother made.” It takes some accident to break out of that pattern, just like the kind of accident in timing or mutation that creates a new kind of animal, maybe human.

The point is how emotional we are about all this. I suppose cats are, too. One is licking my knee seductively at the moment -- hoping I’ll open a cat of catfood. I suppose it had something to do with finding a nipple on the mother cat once, but now this “mother’s little baby” likes cat food better anyway. What’s even more interesting is that I like having my knee licked. Where did THAT come from?

2 comments:

  1. Anonymous9:09 PM

    It's fun trying to decipher cat genetics. We took in a stray cat a couple of years ago, and a few weeks later she had four kittens (one of which died). Even though we already had three cats we ended up keeping all three surviving kittens - they were just too cute to give away - and ended up keeping the mother cat too.
    Baci, the mother, is a rather scrawny calico, although the veterinarian calls her coat "brindle." Of the kittens, Sherbert is relatively large and is orange with white stripes and sort of muddy-colored paws; Merlin is a huge grey-and-black striped cat, and Princess is tiny, about the size of an average 6-month-old kitten (but very fast and agile), and her coloration is similar to Baci's. The kitten that died was a light grey male.
    We're trying to figure out what the father cat looked like, not an easy task given the kittens' vastly different sizes and colorations.

    Peter
    Iron Rails & Iron Weights

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  2. Hi Peter,

    And then to complexify everything even more, cats ovulate in the midst of coition. So if one male breeds them and then leaves, the next male will get a new set of eggs and there will be more kittens by that father.

    Of course, how securely the placenta was attached, how efficient the umbilical cord was, how much space each kitten had among the others -- all makes a difference. Gray males seem to be a little mutated -- often have double front paws, too many toes.

    Whoopeee!

    What I call a "calico" is a cat with black, orange and white in separate patches. A cat with mixed colors, often on a dark background, some people call tortoiseshell and I like to call a "confetti calico." In my experience, these torties are generally a little smaller, a little more quick and predatory, and a little smarter. I call mine "the velveteen lizard" sometimes! As opposed to the big beige one: "blonde butt."

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