rat genetics help

[pastel0711]

im breeding rats for snake food and have noticed my litter has a bunch of different hair types not just color variation. A long with being every colour imaginable(in a rat) the is also super shiny babyX2 normalX2 rough furredX9 and curlyish furX4. The parents all seem to have normal fur so i was wondering what the genetics was on this. I thought curly fur ras like a visual het for hairless but now i dont get it as all parents look normal. Pictures tomorrow hopefully. They are 2 weeks old.

[aldebono]

Maybe I can explain it a little better.

Hairless is it's own gene and it is recessive. The hets do not have any special look to them.
Most rat colors and genes are recessive

Mock hairless, or patchwork, or double rex is a super form of rex. Rex are the rats with curly or wavy hair. The rex gene is a dom (co-dom?), and has no hets.

What I am guessing is one of your females is a poor example of rex. The females do not hold the curly coat as well as the males. Sometimes the only way you can tell a poor rex is the curl in their whiskers.
You are able to see it in the babies because it's just expressed better in pups and then they molt and may lose some curl.

[Sita]

There's over 40 different colors available in rats, FYI,

Here's a link about hair coats: http://www.spoiledratten.com/breedingrats7.html

I've got to head to work so I don't have time to help much more, but pictures would be helpful (and adorable!).

[pastel0711]

these guys are IMPOSIBLE to photograph. they are always running around. these are the best of the worst lol
[IMG][/IMG] This is one of the moms she is dumbo with straight whiskers and regular feeling hair
[IMG][/IMG]This is dad he is regular hair and ears
[IMG][/IMG]The grey one in this photo is the other mom and she has normal ears and norma hair and whiskers
[IMG][/IMG] The pinkish light ones have super curly fur
[IMG][/IMG] majority of the rest have wavy hair with some having normal hair and a few with real shinny hair. only one dumbo baby.
[IMG][/IMG]this is a curly one sorry the pictures sck but they run around like crazy

[sorraia]

The dad is a very poor example of rex, but he is a rex. Some would call it "velveteen", but as far as I'm aware, that is not been proven to be distinct from rex. In the photo it looks like his fur isn't laying perfectly flat, but almost "clumpy" in some places. That's the rexing. I've seen it in my own rats before. They start out wavy looking, then get straight fur when they shed into their adult coats. Chances are the babies won't retain their curls.

Rex is a co-dominant trait, so you only need one rex parent to produce it.

Hairless on the other hand is recessive. In order to produce hairless, both parents need to at least carry it. If you ended up with hairless in either of these litters, it means both parents carried the gene.

As far as colors, looks like one mom is fawn (or beige? hard to tell in the photo), the other is agouti, and dad is Siamese (or Himalayan, again hard to tell in the photo). The babies look like they are black, agouti, fawn/beige, and Siamese/Himalayan. Black and agouti are expected, as those are the "default" colors (where black is recessive to agouti). The beige/fawn babies means dad carries the gene (it's recessive), and the Siamese/Himalayan babies means the mom carries it (also recessive).

[pastel0711]

so this would mean the wavy haired ones are just a more subtle or poorer example of a rex and the curly ones are just a better example comparitavly speaking. the shiny ones must just be appearing different as all the others have some degree of rex. makes sense. Also the one dumbo would suggest that the dad is het for dumbo as it is recessive. Breeding rats has much more genetics than i thought. Its actually as rewarding as breeding my snakes.

[sorraia]

so this would mean the wavy haired ones are just a more subtle or poorer example of a rex and the curly ones are just a better example comparitavly speaking. the shiny ones must just be appearing different as all the others have some degree of rex. makes sense. Also the one dumbo would suggest that the dad is het for dumbo as it is recessive. Breeding rats has much more genetics than i thought. Its actually as rewarding as breeding my snakes.

Yup you got it!

The genetics in rats really is a lot of fun once you get into it. Most colors are fairly simple, in that they are recessive. However some are more of a challenge and/or more interesting in that they work in cooperation with other genes. For example, pearl and merle working only with mink, and Burmese and black-eyed colorpoint working with colorpoint. Different markings are fun too, some being dominant, some being co-dominant, and the varying degrees of penetrance and expression. Then when you start combining all of the above, you can get some real interesting results!

[aldebono]

Sorraia, those babies look awfully pink and balding to me. Could he have a recessive hairless in there and those babies just haven't moulted yet and become obviously hairless?

[sorraia]

Sorraia, those babies look awfully pink and balding to me. Could he have a recessive hairless in there and those babies just haven't moulted yet and become obviously hairless?

There absolutely could be recessive hairless hiding in there. It could also be the rex - some rex will shed bald during their moult into adult fur. Actually, I once had a litter of normal furred babies that moulted bald like that! It was the darndest thing and scared me half to death thinking there was something wrong with them. But they regrew their fur just fine, no problems. Just a really strange moult.

What the OP actually has.. time will tell. If they regrow their fur, they are rex. If they stay bald, the hairless.