Determining age by means of blood samples?

[Theophrastus]

In regards to blood stain analysis methods, aside from the basics, I've also heard that crystalization of the blood sample, can be used in some manner to determine the person's (or animal's) age. There was also something mentioned regarding the nature of the clotting- I would assume this would be during the administration of the necessary antiserum, that some aspect of the coagulation can be used to estimate age.

I was recently reading a biology text, for lack of anything better to do, due to sickness (curse thee common cold!) and skimmed over a brief reference in the text towards forensic analysis of blood samples, though began to grow annoyed as it mentioned some less precise methods used to dissert things like age and race from a blood sample, making vague comments regarding a combination of crystallization, coagulation, etc., which given the level and detail of the text is understandable.

But anyway, my question is, what method is generally used to estimate age, based upon a blood sample, and how does it work? Any ideas, or thoughts? As always, any assistance would be most appreciated.

 

-Theo

Edited May 22, 2009 by Theophrastus
revision of paragraph structure

[Leison]

i dont think age can be estimated by blood.

but sex can be determined by presence of Barr bodies which is found in female.

[Theophrastus]

In terms of sex, you can also test for the presence of chromesomes, however as I said, this was within the text, so I'm guessing it is possible to attain age by means of blood samples. If you have any precise information to demean the statement, I'ld love to have it, however, I generally don't go by gut feelings. The problem I suppose is indicators. If there are no age- type indicators within blood, then it is impossible to extrapolate age. I suppose I should initially have broadened the question: Are there any chemicals, proteins hormones and the like, the quantity or quality of which can be used for the basis of an indication of age?

Edited May 25, 2009 by Theophrastus
sentence structure reform

[Leison]

Barr body is condensed X chromosome in female.

 

presence of foetal Hb can be detected if blood is of a child.more than this i dont think any info about abt age can be obtained frm blood.

[ecoli]

maybe by measuring relative telomere size... but that's widely variant between individuals.

[CharonY]

Worse, it is dependent on the proliferation of the cell from which you look at the telomere.

I am not aware of any marker that can be used to precisely track the age in blood. It is however possible to distinguish between neonates and more adult individuals by tracking the expression of specific fetal proteins/genes.

[Carvone]

I am not aware of a single marker for determining age, but it may be possible to run a multivariate statistical analysis of different components within blood to determine age, similar to identifying the strain of bacteria based on a multivariate analysis of the ratio of all fatty acids in a GC fatty acid methyl ester analysis.

 

It is probable that as an organism ages, some things in blood increase (eg. cholesterol build up) and some decrease but this will vary widely across populations, so only with some sort of multiple regression of a large data set could this be determined, though I am not aware if any study like this has been attempted.