How to do Punnett squares for co-dominance & to do more than 4 squares?

[CoolioTiffany]

I would really love to know how to do a Punnett square for two co-dominance. It seems like something fun to learn, but I only know how to do the Punnett squares for dominant x dominant, dominant x recessive, recessive x recessive, het x het, dominant x het, recessive x het, and I think that's all I know. I also would want to learn how to do more than 4 squares. Any websites or anything you guys can teach me (maybe doing a Punnet square for anything with a co-dom like co-dom x co-dom or dominant x co-dom or recessive x co-dom or het x co-dom.. you get it) or demonstrate? I'm too interested in genetics..

[pankthesnake]

I would really love to know how to do a Punnett square for two co-dominance. It seems like something fun to learn, but I only know how to do the Punnett squares for dominant x dominant, dominant x recessive, recessive x recessive, het x het, dominant x het, recessive x het, and I think that's all I know. I also would want to learn how to do more than 4 squares. Any websites or anything you guys can teach me (maybe doing a Punnet square for anything with a co-dom like co-dom x co-dom or dominant x co-dom or recessive x co-dom or het x co-dom.. you get it) or demonstrate? I'm too interested in genetics..

As far as I know, it should work the same as recessive x recessive. A snake with a co-dom gene is basically a visual het, with the super form being homozygous. Dominant is still a het, but the super form is visually the same as the het.

[LGL]

http://www.newenglandreptile.com/genetics_codom.html

[CoolioTiffany]

As far as I know, it should work the same as recessive x recessive. A snake with a co-dom gene is basically a visual het, with the super form being homozygous. Dominant is still a het, but the super form is visually the same as the het.

Oh ok so like for the Pastel gene it would be like Pp but P being the super form and the p being the Pastel gene or normal gene (or vice versa?)?

[pankthesnake]

Oh ok so like for the Pastel gene it would be like Pp but P being the super form and the p being the Pastel gene or normal gene (or vice versa?)?

Yeah.

If you crossed Pp x Pp (pastel x pastel) you would get pp (normal); Pp (pastel) twice and PP (super pastel)

[Whoodnballs]

Yeah.

If you crossed Pp x Pp (pastel x pastel) you would get pp (normal); Pp (pastel) twice and PP (super pastel)

Sorry this is going to get long...

Usually in genetics PP is used for the wildtype(normal) and pp would be recessive, in this case super pastel, and Pp would be the heterozygous for or Pastel.

http://www.changbioscience.com/genetics/punnett.html
This is the punnett square calulator I use to figure out my genetic frequencies. I'm sure there are better ones out there, heck sometimes it even comes up with the wrong possible genotypes. If you search for "punnett square calculator" you should be able to find one that works for you. Really you only need one of these also if you are doing somthing like 5 trait crosses and you get over 600 possilbe outcomes. usually only 16 or 32 genotypes in those 600 possibilities, but its better than writing out all those genotypes. or using a posterboard to make the square.

Which brings me to the more than 4 square punnett squares. say you take a spinner blast and cross it with a woma lesser. The Spinner Blast of course is Spider(Ss)xPinstripe(Pp)xPastel(Tt) the Woma Lesser would be Woma(Ww)xLesser(Ll). Because the Spinner Blast has no woma or lesser in it when writing out its genotype you would use the wildtype for those making its genotype SsPpTtWWLL, respectivly the Woma Lesser would be SSPPTTWwLl. Be sure to always put the same trait in the same spot or you will have unmatched letters for the results. i.e. SsPpTtWWLL x WwLlSSPPTT would give something like SWPlTSWPLT and that make no sence. But SsPpTtWWLL x SSPPTTWwLl = SsPPTtWwLL or a Woma Bumble Bee. punching this combo in to the calculator gives you 3.125% chance of getting anything from a Normal(SSPPTTWWLL)all wildtypes to a Woma Lesser Spinner Blast(SsPpTtWwLl)Heterozygous for all traits. 32 different combonations.

Using a rececive trait is as simple as using two lowercase letters in place of the heterozygous pair. just remember crossing anything that isn't het for a recessive trait, only gives you het for that trait. i.e. Spinner x Albino would be SsPpAA x SSPPaa that would give you Normals, Spiders, Pinstripes and Spinners, all het for albino.

I think that should cover it a bit for you. If you have any questions let me know. And if I made any mistakes someone please let me know.

Here is another page that I found that just goes over the punnett square and dihybrid crosses in a punnett square.
http://www.docfleetwood.net/wiki/tik...unnett+Squares

[Watever]

A lot of people use the small letter as the normal trait and the Capital one has the recessive gene.

I find it easier to use the "n" as the normal or wildtype trait. and use a Capital for the dominant/codominant genes. And use a small letter if it's recessive.

That way you get this :
Pastel : Pn
Super Pastel : PP
Cinnamon : Cn
Super Cinnamon CC
Pewter : PnCn
Ghost : GG
Het Ghost : Gn
Pewter Ghost : PnCnGG

If you want to breed a Pastel to a Cinnamon, then you do this :
Pastel : Pnnn
Cinnamon : nnCn

and you get

Punnett Square

Pnnn x nnCn

        Pn	Pn	nn	nn
nC	PnCn	PnCn	nnCn	nnCn
nn	Pnnn	Pnnn	nnnn	nnnn
nC	PnCn	PnCn	nnCn	nnCn
nn	Pnnn	Pnnn	nnnn	nnnn


Genotype Frequencies: 
PnCn:    4 ( 25% ) Pewter
Pnnn:    4 ( 25% ) Pastel
nnCn:    4 ( 25% ) Cinnamon
nnnn:    4 ( 25% ) Normal

Using the first method would have also work but I think it's harder to read.

Ppcc x ppCc

        Pc	Pc	pc	pc
pC	PpCc	PpCc	ppCc	ppCc
pc	Ppcc	Ppcc	ppcc	ppcc
pC	PpCc	PpCc	ppCc	ppCc
pc	Ppcc	Ppcc	ppcc	ppcc


Genotype Frequencies: 
PpCc:    4 ( 25% ) Pewter
Ppcc:    4 ( 25% ) Pastel
ppCc:    4 ( 25% ) Cinnamon
ppcc:    4 ( 25% ) Normal (the genotype to read it get confusing I think)