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Saccharomyces cerevisiae BY4743, wild type? - (Jun/22/2012 )

hi guys, i got a quick question but it confused me a couple of time. what is wild type of yeast? Yes...... i know it is an embarrassing problem for a biologist. But sometimes i am really not sure what it is.

For example, Saccharomyces cerevisiae BY4743, Genotype: MATa/α his3Δ1/his3Δ1 leu2Δ0/leu2Δ0 LYS2/lys2Δ0 met15Δ0/MET15 ura3Δ0/ura3Δ. As genotype showed, a couple of genes have been disrupted. however, it was considered as wild type in some literautres. So why? any help will be appreciated. thanks.

-BlooDemon-

if you check: http://wiki.yeastgenome.org/index.php/Commonly_used_strains#BY4743 , its obvious its not a "wild type" as in: found in nature , and nothing human has been done with it...

So its not a "real wild type" , what they mean (I think, havent checked the papers) in those papers is that they used the "original (wild) type" as been created the first time.

-pito-

pito on Fri Jun 22 18:34:51 2012 said:


if you check: http://wiki.yeastgen..._strains#BY4743 , its obvious its not a "wild type" as in: found in nature , and nothing human has been done with it...

So its not a "real wild type" , what they mean (I think, havent checked the papers) in those papers is that they used the "original (wild) type" as been created the first time.


Appreciate your help. it's much clear for me now.

-BlooDemon-

BlooDemon on Sun Jun 24 09:54:18 2012 said:


pito on Fri Jun 22 18:34:51 2012 said:


if you check: http://wiki.yeastgen..._strains#BY4743 , its obvious its not a "wild type" as in: found in nature , and nothing human has been done with it...

So its not a "real wild type" , what they mean (I think, havent checked the papers) in those papers is that they used the "original (wild) type" as been created the first time.


Appreciate your help. it's much clear for me now.

No problem.

BTW: if you check http://onlinelibrary...>3.0.CO;2-2/pdf (the paper where they describe the "parents" of your strain, its obvious its not a real "wild" type as most people would "see" a wild type. Its clear its a wild type generated in the lab)

And check: http://www-sequence....oject/faqs.html where you see how they made your strain (BY4743 MATa/a his3D1/his3D1 leu2D0 /leu2D0 lys2D0/LYS2 MET15/met15D0 ura3D0 /ura3D0 (4741/4742) homozygous diploids are in the BY4743 background unless 4730/4739 is indicated).

I must admit its not that clear and that using "wild type" is a bit weird.

PS. if I was you (and had some more time) I would send an email to one (or more) of some of the authors mentioning this strain as a wild type.. and just ask them why they call it a wild type...
If you do, be sure to let us know.

-pito-

I have seen "wild type" used where the term indicates the strain/variant before a deliberate mutation was made. That is, the "wild type" is the "parental" strain.

If that helps :)

-leelee-

leelee on Mon Jun 25 07:10:59 2012 said:


I have seen "wild type" used where the term indicates the strain/variant before a deliberate mutation was made. That is, the "wild type" is the "parental" strain.

If that helps


I know. Thats what I wanted to say with "original type".
But I do find it very confusing and rather idiotic to speak of a wild type when in fact its something created in a lab.

-pito-

I think the reason that the term "wild type" has a broad or loose meaning comes from the fact that in a lot of circumstances "wild type" doesn't really exist in the way that the term was originally meant to be understood.

I know what you mean about it seeming confusing to use the term "wild" but have it mean something quite different from the literal meaning of wild :)

I think when a term is misused enough times in the same way, it kind of adopts the new meaning :)

Science seems to have a habit of doing this (either creating new words, or making new meanings for existing words).

-leelee-

hi guys, thanks for all the comments. As Pito sugggested, i did enquire the "wild-type" things from some guys who did mention the "wild-type"in their papers. You guys are correct it does mean original or parental strains. i post two of their answers as following:

1. Your question is a good one. You are correct that BY4743 is not wild type in all respects having mutations in several genes. It is the original strain used for further modifications. You’ll find this usage of the term “wild type” in all yeast genetics papers but it is not strictly accurate.

2. We used BY4743 as the parental strain of all mutants. BY4743 is a designer yeast strain. all auxotrophic markers are completely deleted by homologous recombination.
You are correct in that it is not living in nature, but microbiologists use this strain to disrupt genes by auxotrophic or drug resistance markers, thus we call it wild type strain.

You guys really helped me out. thanks again. By the way, Pito, your logo is so special. Is that you, or your father, or grand? Anyway, it's adorable!

all the best

-BlooDemon-

BlooDemon on Thu Jul 12 15:18:57 2012 said:


hi guys, thanks for all the comments. As Pito sugggested, i did enquire the "wild-type" things from some guys who did mention the "wild-type"in their papers. You guys are correct it does mean original or parental strains. i post two of their answers as following:

1. Your question is a good one. You are correct that BY4743 is not wild type in all respects having mutations in several genes. It is the original strain used for further modifications. You’ll find this usage of the term “wild type” in all yeast genetics papers but it is not strictly accurate.

2. We used BY4743 as the parental strain of all mutants. BY4743 is a designer yeast strain. all auxotrophic markers are completely deleted by homologous recombination.
You are correct in that it is not living in nature, but microbiologists use this strain to disrupt genes by auxotrophic or drug resistance markers, thus we call it wild type strain.

You guys really helped me out. thanks again. By the way, Pito, your logo is so special. Is that you, or your father, or grand? Anyway, it's adorable!

all the best


Well, thats what I allready assumed.
To be honest, I do not like this use (rather abuse) of words.
A wild type (to me and many people) is a type you will find in nature.. not something created in a lab. If they want to "show" its the first strain created, then call it the parental strain or whatever word they want to invent for it.. but dont use wild type.

But thats just my opinion.

The logo is H.M. "Howlin' Mad" Murdock

-pito-