Litter with multiple characteristics

[momofmany]

I've been reading your responses to the various inheritance questions and am still confused by my last litter from a feral mom.

Kitten #1 - orange tabby long haired male
Kitten #2 - orange/white short haired male polydactyl
Kitten #3 - black short haired female
Kitten #4 - black long haired male

The mother was a long haired tortie, her mother was an orange short hair, her mother a tortie and her mother an orange/white (5 generations in total over 10 years). I saw a new tom this year that was long haired black and assumed it to be the father of the black ones.

The polydactyl trait has never before appeared in my feral colony and what is interesting is at 6 months old, he is starting to sprout black hairs in his tail. I'm assuming a separate father for him in this litter due to the dominance of the polydactyl gene.

How far can inheritance traits go back thru a lineage? Am I getting mixes due to multiple fathers, or from longer hereditary chains?


Thanks for your insights!

 

[elizabeth a.]

Well, "hereditary chains" go back for ever: to Adam or to the critter that crawled out of the primeval ooze, depending on your way of looking at Life!
One of the real problems in genetics is that genes can "go underground" for a very long time if they are recessive. Mistakes happen all the time as DNA is replicated to produce eggs and sperm...we call these "mutations" and they are the cause of all the variation we see. But a new mutation will be hidden for a very long time if it is recessive. It's very rare to start with, so is passed on quietly and never shows up until it is common enough that we start to see the progeny of matings between individuals that both carry copies of the gene.
You raise some interesting points with this question. For instance, we know that litters can indeed have multiple fathers. Also, as you say, the polydactyl gene is dominant, but it has something that we call variable expressivity. That means that an animal with the gene might not even show its effects, or, if it does show them, you might have 1-4 paws affected, and the number of extra toes will also vary. Those of you who've seen such cats know what I mean, I'm sure!
Short hair is dominant to long, so 2 long-haired parents shouldn't be able to produce a short-haired kitten.
I'm going to play with your information when I have a bit more time this weekend and get back to you on what it tells me in some more detail!

 

[elizabeth a.]

I'm back!
I looked at that litter information, and they could all be from the same dad, but he must be a black short-hair, not long-hair. Why?
1. half the kittens have short hair, a dominant trait. Mom is long (ll), so dad must be short, carrying long (Ll).
2. the black female has to be oo, getting a black gene from each parent. O and o are on the X, dad has only one X, so he's o and black. All the other colors fit this.
3. kitten number 2 has white spots and you don't mention any on mom, so dad must have a few white spots, so he's probably Ss.
3. dad may show extra toes, maybe not, as this dominant gene has variable expression. The same could be said of mom, but you've never seen polydactyl cats before in your colony, so let's blame dad! He's Pdpd we assume.
And that's as far as the detective work can go........

 

[momofmany]

Thank you! The mom cat got pregnant elsewhere and only delivered them on my doorstep, in fact, each generation that I described happened this way. I'm in a rural area so rarely get to see the toms that roam my area - the females that stay at my house are typically neutered and don't attract toms.