Will a smart person teach me about cat genes?

[Emily Lake]

Genetics interests me. But I am nearly ignorant. I know genes exist. I know there's chromosomes and things. I know some come from mom, some come from dad - at least in mammals. I know some amphibians have squishy genders. I know some genes mutate. I understand recessive and dominant genes because my dad was red-green color blind, so I'm a carrier. I've got most of the pop-science stuff hammered out okay, but beyond that, consider me a willing mind ready to absorb.

Let me lay out what I want to know. Dogs have been bred for eons as partners to humans. We've manipulated their genes for preferred physical and behavioral characteristics, to a point where we've created sets of genes that "breed true", and carry forward from one generation to the next with identifiable traits. There are many well-defined dog breeds. If a pure-bred dog gets out and gets funky with a random mutt, the offspring will resemble the pure-bred well enough that you can usually identify what sort of dog it was. As I understand it, this holds for a few generations... you can see that a dog is "part doberman" or whatever.

The same isn't true for cats. Cats haven't been with humans for quite as long as dogs, but certainly for long enough to have established at least a few well-defined breeds, such as siamese and abyssinian. But if a pure-bred cat gets out and has a midnight rendezvous with the tom next door, you're likely to get a random assortment of DSH (domestic short hair) out of it! You might still get points on the face, ears, and tail if one of the parents was siamese... but you're also likely to get stripes and whorls and spots. Even the coloring is not guaranteed to match either of the immediate parents.

My vet very, very briefly explained to me that cat genes are "jumpy". They bounce around and mix a lot, they don't hold together in groups or chains, so clumps of characteristics don't tend to hold together and get passed on as much. This means that it's very hard for "breed characteristics" to hold true from one generation to the next - if there's any interjection of other genetic material in there, you get mutts in short order. It also means that within just a couple of generations, you completely lose any breed characteristics if cats are left to mate uncontrolled.

So... First: Is what my vet told me true? Second: Can one of you well-educated people explain it in more detail, because I'm quite interested.

Thanks!
Emily

 

[steve_bnk]

As to genetics feral cats ad dogs tend to return to their genetic programming and behave pretty much like their wild cousins.

Newborn cats and dogs imprint humans as their group.

I'd question as to how much the connection between dog and human is actually genetic. I'd say it is more operant conditioning and imprinting.

If breeding is limited to one breed then I do not see what gene jumping means.

if breeding is mixed genetics works like on any other organism.

 

[Petrel]

. Cats haven't been with humans for quite as long as dogs, but certainly for long enough to have established at least a few well-defined breeds, such as siamese and abyssinian.

If we assume that dogs have been associating with humans since nomadic times and cats only became domesticated after agricultural settlement, that's true. On the other hand, human were not breeding or even selecting their dogs until they were settled, so it's roughly the same period of deliberate interference. There are 40-odd recognized feline breeds, if I recall, while canine breeds are in the hundreds, and the difference from one breed to another, far more pronounced than in cats. This would strongly suggest that your vet is right - and, really, he had to pass exams on tis stuff!
This site will help answer your questions far better than I can.

 

[Emily Lake]

Okay. That's not what I want to know.

Let me try again - I'm interested in the genetics-as-a-concept side of it, not the "what makes one breed distinct from another" side of it. I'm interested in why one species seems to be more "stable" at passing on its genes from one generation to the next, while the other seems more... "fungible" for lack of a better term. What are the mechanics at play? Who does this work? Are there specific terms involved? Are there other species like this?

Sure, my vet needs to learn some stuff... but I doubt she actually studies genetics as a science. No more so than my gynecologist would have needed to study anything at all about epigenetics or retroviruses. I am hoping someone around here happens to have made a hobby (or a real life study!) of genetics and feels like sharing

 

[Petrel]

So.... not really about cats then?

Okay, I imagine the difference wouldn't be that any one species is more genetically malleable than another, but rather that the gene pool from which the modern species originated was different - bigger, more varied, longer established, more stable... something. You may need to do background reading.

 

[J842P]

I can't really fathom what your vet might be referring to. This might be because your vet was trying to put in in "laymen's" terms or because your vet was just wrong.

I wouldn't really go to a medical doctor about information regarding molecular genetics.

 

[barbos]

Dogs just have greater genetic diversity than cats.

 

[braces_for_impact]

Just off the top of my head, and for all I know completely wrong, but the characteristics you see may not necessarily be completely due to genetics. Dogs are pack animals, easily bred and controlled. Breeding true becomes easy enough because a dog's instinct is to follow the pack leader. So, we end up with a lot of very distinct dog breeds because they were bred for specific tasks, and hence posses specific traits.

Cats, er, not so much. They are less malleable to control, as any cat owner can attest. There are breeds, but as you mention, they're a lot less distinct from each other. We haven't been breeding them for many generations to perform specific tasks. Some of that has gone on, to be sure, but not nearly to the extent it has happened to dogs.

Dogs are useful. They are tools shaped to perform a specific function. Cats are well, cats and do what they want. Some were bred for specific traits, but usually just traits considered desirable by an owner, (maybe as just pets) but not for a specific task like hunting, shepherding, guard duty, etc.

As I said, I may be well off the mark, but this makes sense to me.

 

[Emily Lake]

So.... not really about cats then?

Not really, no. Cats are just a jumping off point, because that's the case where this particular sort of difference in how blocks of traits are passed on came to my attention.

Okay, I imagine the difference wouldn't be that any one species is more genetically malleable than another, but rather that the gene pool from which the modern species originated was different - bigger, more varied, longer established, more stable... something. You may need to do background reading.

But reading requires effort, and I've never been particularly good at self-study. I've always learned better in group settings where I can interact and discuss ideas with other people in a more active fashion. Plus, I'm actually kind of lazy .

 

[skepticalbip]

Disclaimer first: I know squat about genetics.

Given this, I would say that it would have to just be the nature of the critters. Dogs are obedient and trainable so they do what you expect and follow the rules of genetics. Cats don't give a shit what is expected of them so ignore those rules.







O.K. there is no need to tell me that that has nothing to do with genetics... It was just a weak attempt at humor.

 

[Emily Lake]

I giggled, so in my view, your weak attempt was successful.

Granted, my sense of humor does not fall within the normal distribution... so that may not be a win for you.

 

[Rilx]

I agree with BFI, it's about the difference between independent and pack animals. Distinct breeds don't change dog's nature and welfare as a pack animal, because they are made from human (pack leader) viewpoint. The human/dog pack works well; another matter is that if this kind of breeds happened in wolf packs, they would soon become selected out.

Thinking of cats, what kind of human planned breeds would preserve (or even streghten) their independent nature? I can't think anything at all.

 

[Loren Pechtel]

My mother's cat was the result of a show cat getting out one night.

The Persian mother was obvious.

 

[J842P]

Dogs just have greater genetic diversity than cats.

There is really no basis to be claiming that.

 

[Bronzeage]

Okay. That's not what I want to know.

Let me try again - I'm interested in the genetics-as-a-concept side of it, not the "what makes one breed distinct from another" side of it. I'm interested in why one species seems to be more "stable" at passing on its genes from one generation to the next, while the other seems more... "fungible" for lack of a better term. What are the mechanics at play? Who does this work? Are there specific terms involved? Are there other species like this?

Sure, my vet needs to learn some stuff... but I doubt she actually studies genetics as a science. No more so than my gynecologist would have needed to study anything at all about epigenetics or retroviruses. I am hoping someone around here happens to have made a hobby (or a real life study!) of genetics and feels like sharing

One thing which is important to understand about "breeds" is that breed characteristics are very superficial. A cat is still a cat on the inside. What your vet probably means about jumping genes is the genes which determine things like fur color or hair length are likely to be different in kittens from the same litter.

 

[Malintent]

Cats can litter kittens from multiple males. Dogs cannot.
Dogs have served as a utility for man for milenia. Cats have never.
Dogs may have greater genetic diversity due to man's influence on their selection. Cats may have greater reproductive diversity, due to their ability to have multiple sires.

In any case, genetics is genetics.. In all mamals, gene sharing between male and female works the same. (doesn't it?)

- - - Updated - - -

Okay. That's not what I want to know.

Let me try again - I'm interested in the genetics-as-a-concept side of it, not the "what makes one breed distinct from another" side of it. I'm interested in why one species seems to be more "stable" at passing on its genes from one generation to the next, while the other seems more... "fungible" for lack of a better term. What are the mechanics at play? Who does this work? Are there specific terms involved? Are there other species like this?

Sure, my vet needs to learn some stuff... but I doubt she actually studies genetics as a science. No more so than my gynecologist would have needed to study anything at all about epigenetics or retroviruses. I am hoping someone around here happens to have made a hobby (or a real life study!) of genetics and feels like sharing

One thing which is important to understand about "breeds" is that breed characteristics are very superficial. A cat is still a cat on the inside. What your vet probably means about jumping genes is the genes which determine things like fur color or hair length are likely to be different in kittens from the same litter.

.. and those differences may be due to the two kittens from the same litter havng genes from two different fathers.

.. perhaps the vet meant that cats have more recessive genes than other mamals tend to have. <shrug>

 

[Emily Lake]

I agree with BFI, it's about the difference between independent and pack animals. Distinct breeds don't change dog's nature and welfare as a pack animal, because they are made from human (pack leader) viewpoint. The human/dog pack works well; another matter is that if this kind of breeds happened in wolf packs, they would soon become selected out.

Thinking of cats, what kind of human planned breeds would preserve (or even streghten) their independent nature? I can't think anything at all.

Behaviorally, you may have a point. But what about the physical traits?

 

[Emily Lake]

Cats can litter kittens from multiple males. Dogs cannot.
Dogs have served as a utility for man for milenia. Cats have never.
Dogs may have greater genetic diversity due to man's influence on their selection. Cats may have greater reproductive diversity, due to their ability to have multiple sires.

In any case, genetics is genetics.. In all mamals, gene sharing between male and female works the same. (doesn't it?)



.. and those differences may be due to the two kittens from the same litter havng genes from two different fathers.

.. perhaps the vet meant that cats have more recessive genes than other mamals tend to have. <shrug>

Hmm. That's worth thinking on.

Are genes actually binary in this fashion - either dominant or recessive? My memory is tickling, insisting that there's such a thing as "co-dominant" genes. Are some genes "more recessive" than others? Or "more dominant"? Is there a degree to which they're a spectrum?

 

[Rilx]

I agree with BFI, it's about the difference between independent and pack animals. Distinct breeds don't change dog's nature and welfare as a pack animal, because they are made from human (pack leader) viewpoint. The human/dog pack works well; another matter is that if this kind of breeds happened in wolf packs, they would soon become selected out.

Thinking of cats, what kind of human planned breeds would preserve (or even streghten) their independent nature? I can't think anything at all.

Behaviorally, you may have a point. But what about the physical traits?

By behavior you mean pack and independent behaviors? They are genetically complex: several genes define several properties which together produce this or that behavior; there are no single pack or independence genes. Pure physical traits instead may depend on only few - or even single - genes.

 

[Malintent]

Cats can litter kittens from multiple males. Dogs cannot.
Dogs have served as a utility for man for milenia. Cats have never.
Dogs may have greater genetic diversity due to man's influence on their selection. Cats may have greater reproductive diversity, due to their ability to have multiple sires.

In any case, genetics is genetics.. In all mamals, gene sharing between male and female works the same. (doesn't it?)



.. and those differences may be due to the two kittens from the same litter havng genes from two different fathers.

.. perhaps the vet meant that cats have more recessive genes than other mamals tend to have. <shrug>

Hmm. That's worth thinking on.

Are genes actually binary in this fashion - either dominant or recessive? My memory is tickling, insisting that there's such a thing as "co-dominant" genes. Are some genes "more recessive" than others? Or "more dominant"? Is there a degree to which they're a spectrum?

In short, yes. not necessarily binary... and perhaps the Vet was implying that Cats have more recessive (or a greater number of recessive) genes on average than other mamals.