The chicken and the ink

[MichelleL11]

Unfortunately, the effect of being able to get comparison material (bones) quickly and easily is eliminated. Building such a database is notoriously difficult and lengthy.


As for the durability of egg white, it should be noted that it was used, among other things, for gilding with real gold leaf. Quote: "These gildings are characterized by special luster and durability, their durability can be calculated after centuries." ( Wikipedia, section "Use in bookbinding" )

Hi, bi3mw:

I agree that building the database for ovalbumin (protein) for particular strains of chickens is going to take some time.

I did find this publication concerning cross-species comparison:

You are not allowed to view links. Register or Login to view., Li et al.

On second thought -- this is just too complicated -- here's one that focuses on species differentiation in just the yolk -- more focused on the questions we're trying to answer:

You are not allowed to view links. Register or Login to view., Liu et al.

And a general discussion of the protein's presence in chicken products (eggs):

You are not allowed to view links. Register or Login to view., Kanaka et al. (I guess there is a whole family of serpin proteins?)

I was actually initially concerned that albumen could be so evolutionarily constrained that it would not differ significantly between chicken breeds -- and that could still be the case.  But at least we know that it does differ enough between species to be used for some sort of identification -- I wasn't sure that would be possible.

Also, a very clear initial complicating factor is that there appears to be three very, very similar genes in chickens (resulting from gene duplication in the far distant evolutionary past).  The result is there may be a complex relationship between these sequences that could be tough to tease out (e.g. three similar genes in each specific species -- how would SNPs in the albumin be differentiated from maybe being protein sequence from one or the other of the very similar proteins?).  However, I do note that actual production of these two further proteins is still being figured out -- so if these ovalbumen-like genes (X and Y) are used to make proteins very, very infrequently, then maybe that issue would go away.

You are not allowed to view links. Register or Login to view., DaSilva et al.

So -- don't mean to be a "nay-sayer" but there are definite issues that would have to be figured out to get a confident identification using ovalbumen.

It is worth thinking about these things so the complications of structuring these types of experiments can be understood -- so that the answer to -- "Why don't they do X DNA sequence or Y protein sequence?" may be it just isn't possible right now (or may never be possible given the structure of that DNA or protein -- it may just not be a good choice in order to differentiate).

But I do appreciate the board being willing to think about these things in a sophisticated fashion!