Doorways into the murky world of genetics?

[plasticknives]

I have been following some of these genetic threads for a while, and I am sincerely interested in learning something about all this mendelian genetics and the like.

However, as an arts student
most of what I'm seeing in this sub-forum looks to me like.....well, gibberish.

I've read and understand the Genetics FAQ, but I was hoping some of you who are more involved in the genetics - and all this hidden gene, F1 and dilute talk- would be able to think back to when they were first starting out and suggest any good books, sites, papers or resources that were really helpful in explaining (cornsnake-related) genetics to you.

I also know that there are some people on this site involved at universities, anyone published anything particularily interesting or relevant that I could potentially find in the campus library?




Alternatively, I'd love to hear some stories on how you got involved with the genetics side of cornsnakes- how many of you came from a completely unrelated background and got into genetics purely through your love of snakes?

 

[Susan]

I made an attempt to help another member with a genetics tutorial and would be glad to try to help you to understand how it all works. Here is a link to my attempt to get you started. And feel free to ask for private lessons if you want.

http://www.cornsnakes.com/forums/showthread.php?t=41890

The Corn Snake Morph Guide, which can be purchased at CCCorns, can help with alot of the details. http://www.cccorns.com/

I'm one of the lucky ones. I understood Mendelian genetics way back when as a student in school (and no, I was not taught by Mendel himself, but close). I may not know everything, but enough to know something of what the experts are talking about (except the boa experts as they use extraterrestrial genetics).

 

[plasticknives]

Thanks very much Susan!

I'll do a bit of reading on my own and once I have more of a general understanding I'll likely take you up on those "private lessons."

 

[Joejr14]

Much like Susan, most of the Mendellean genetics that I learned in high school stuck with me. When I first got here I was able to ask some basic questions and then plug and play with the genes in punnett squares. Once I did that, it all came back.

If you have some specific questions I'd be more than happy to help you out. Likewise, I'm online every weeknight except Monday, so if you had something to go over we could do that in the chat room---or on AIM. My SN is the same here as it is there.

Best advice---keep asking questions until you learn it. You might have a problem that you just can't understand---until someone else explains it in a different way and it clicks. You just never know.

 

[plasticknives]

Thanks Joe :dunce:

I understand the whole Punnet Square thing, as long as you're dealing with two alleles.... more (ie. dihybrid crosses?) and I start to get confused. I guess you just have to keep breaking it down?

Its partially the jargon that I can't quite grasp yet, but I'm sure that will come with time.

 

[Joejr14]

Don't let multiple alleles scare you---it doesn't make it any harder provided you can foil correctly.

For example, we'll use my pair of normals het sunkissed and charcoal.

We'll define sunkissed by (s) and charcoal by (c).

The genotype would be: CcSs

So, your gamete combos would be: CS, Cs, cS, cs. Plug those into the Punnett Square and away you go.

Say I was lucky enough to have an extra gene added into that mix. Let's go with hypo (h).

The genotype: CcHhSs. Just foil it out.

CHS, CHs, ChS, Chs, cHS, cHs, chS, chs. There are your gamete combos and you simply plug those into the Punnett Square and you've got your outcomes.

The neat trick would be that when looking at a genotype, heterozygous pairs will obviously give (Xx) of any given trait, and you can cheat.

Let's say you had a Caramel het amel motley (ccAaMm) You will have four gamete combos.

Let's say you had a Caramel Hypo Lavender het bloodred and motley. How many possible gamete combos? Four.

What about a normal het caramel, hypo, lavender, bloodred and motley? You have 5 genes in play....each is heterozygous. 2^5= 32.

That little trick helps a TON when foiling as a check on your math.

 

[kathylove]

Chuck Pritzel (author of the Morph Guides) has just come out with a new Genetics for Herpers book. It is only 84 pages, but packed with more than most people ever need to know! I will be selling it soon, and I am sure Chuck probably has it on his website as well. I believe the price will be $10.

 

[plasticknives]

Don't let multiple alleles scare you---it doesn't make it any harder provided you can foil correctly.

For example, we'll use my pair of normals het sunkissed and charcoal.

We'll define sunkissed by (s) and charcoal by (c).

The genotype would be: CcSs

So, your gamete combos would be: CS, Cs, cS, cs. Plug those into the Punnett Square and away you go.

Say I was lucky enough to have an extra gene added into that mix. Let's go with hypo (h).

The genotype: CcHhSs. Just foil it out.

CHS, CHs, ChS, Chs, cHS, cHs, chS, chs. There are your gamete combos and you simply plug those into the Punnett Square and you've got your outcomes.

The neat trick would be that when looking at a genotype, heterozygous pairs will obviously give (Xx) of any given trait, and you can cheat.

Let's say you had a Caramel het amel motley (ccAaMm) You will have four gamete combos.

Let's say you had a Caramel Hypo Lavender het bloodred and motley. How many possible gamete combos? Four.

What about a normal het caramel, hypo, lavender, bloodred and motley? You have 5 genes in play....each is heterozygous. 2^5= 32.

That little trick helps a TON when foiling as a check on your math.

Okay, lets see if I understand properly here.
So for that trick you'd ignore what is homologous because either way the offspring will inherit that allele from the parent, but in dealing with heterozygous traits, you take 2 to the power of the number of hets, which will equal the number of different alleles that you could get from that parent....

and that would be one side of your punett square, which you would pair with another to find the possible offspring.

yes?

 

[Joejr14]

Yes, you ignore homozygous traits because they can only give one gene pair---no matter what. Heterozygous gives you two options instead of one.

 

[plasticknives]

Yes, you ignore homozygous traits because they can only give one gene pair---no matter what. Heterozygous gives you two options instead of one.

right, homozygous.

see, it's the language and jargon that most throws me off.

Thank you VERY much for that example, it was very helpful!

 

[plasticknives]

Also: Thanks for the pointer kathy, I'll be sure to check it out.

 

[Drizzt80]

I'd recommend Micks' Progeny Predictor (http://home.comcast.net/~spencer62/cornprog.html) as the single best resource for getting a better handle on the genetic combinations you can get. It's great cause you can quiz yourself and see if you've 'gotten it' yet!

D80

 

[plasticknives]

I'd recommend Micks' Progeny Predictor (http://home.comcast.net/~spencer62/cornprog.html) as the single best resource for getting a better handle on the genetic combinations you can get. It's great cause you can quiz yourself and see if you've 'gotten it' yet!

D80

I really wanted to download the cornsnake morph calcualtor and now this- but unfortunately (well, in this case, at least!) I'm a Mac user. So no go.

Thanks for the suggestion, though.... it's things like that that I was/am looking for!

 

[Drizzt80]

I really wanted to download the cornsnake morph calcualtor and now this- but unfortunately (well, in this case, at least!) I'm a Mac user. So no go.

Thanks for the suggestion, though.... it's things like that that I was/am looking for!

Bummer for you . . . I am forced to use a Mac at work . . . :sidestep:

. . . anyway, there's an online one here:
http://www.kornnatterlexikon.de/index.php?action=6

D80

 

[plasticknives]

Bummer for you . . . I am forced to use a Mac at work . . . :sidestep:

. . . anyway, there's an online one here:
http://www.kornnatterlexikon.de/index.php?action=6

D80

Oh ouch!
Thanks for the online link, it's pretty fun to play with!

I actually really like my Mac- in most instances, its a real joy. I do a lot of essays (which are done on word for macs) music composition, and image related work, though... which what they're really made for.
And the internet, but that's fairly similar on all machines.
Im not into gaming or anything, and it's only a very few instances (like this one) where I run into trouble-
and the lack of viruses/maintenance is worth that to me. Plus I'm a sucker for a well designed user interface.

Ideally, I'd run a Linux machine, but I don't really have the time (or knowledge) to set one up for myself.

Really though, Mac or PC......I figure as long as the user's happy, the computer is good. And I'm pretty happy with mine.

 

[Drizzt80]

Really though, Mac or PC......I figure as long as the user's happy, the computer is good. And I'm pretty happy with mine.

. . . Agreed. I'm getting more comfortable working with the Mac at work, but prefer my PC.

D80

 

[tyflier]

plasticknives-

From someone who came into cornsnakes only a few months ago and remembered absolutely nothing about genetics from high school other than dominant/recessive relationships, I highly recommend 2 books for a beginner:

Kathy Love's book has an incredibly easy to follow genetics tutorial that makes it easy for the thickest skulls to comprehend(like mine).

Couple that with the Cornsnake Morph Guide(I just got the '07 edition), and you will be looking at cornsnakes in a whole new way.

Playing with those genetics calculators is a whole lot of help and fun, too. You can test yourself...make sure you are really getting it(like me )