DNA and Northamptonshire Police

[dsm]

I think the mistake at this website (http://www.northants.police.uk/dna/02.htm) alluded to in Randi's commentary is in the picture which says "half our DNA comes from our parents". That begs the question of where does the other half come from?

;)

[Rolfe]

Originally posted by dsm
That begs the question of where does the other half come from?Or maybe it raises or poses the question? :D

Actually, that's the only thing I could see either, but it was such a silly slip-up (as the correct situation was explained in more detail in the rest of the text, and having read that you could see that the diagram also had it right) that I don't quite see why it's worth making a big deal about it.

It's not as if they actually meant it.

Rolfe.

[geni]

They did make the same slip up twice though (hold your mouse over the picture).

[ShowMe]

Originally posted by geni
They did make the same slip up twice though (hold your mouse over the picture).

Not so much a lsip-up, I think, as poor grammar on the caption. The acoompanying text is correct; they just missed putting in the words "each of" in front of "our parents".

[Mr. Skinny]

Originally posted by dsm
I think the mistake at this website (http://www.northants.police.uk/dna/02.htm) alluded to in Randi's commentary is in the picture which says "half our DNA comes from our parents". That begs the question of where does the other half come from?

;)
That's the error I caught also. Sent Randi an e-mail about it around 6 pm EST.

Guess I wasn't the only one.

The other half comes from aliens dontcha know. :)

[Peter Morris]

There is no error, save for an unclear description. The caption "half our DNA comes from our parents" is carelessly worded, but the intended meaning (from each of our parents) is clear, and is stated correctly in the text.

Your reader was probably confused by the picture of the child, showing a blue section inherited from the father, a purple section inherited from the mother, and an unexplained red section.

An extra line in the text would have made things more clear. Take the line "[DNA]is found in almost every one of the 75 trillion cells in the body." Instead of "almost every one" say "most." Follow that with the line "The exception is red blood cells, which do not contain a nucleus, and make a substantial percentage of the total."

[HarryKeogh]

i think the mistake is that the people on the website have no genitals.

[DrMatt]

As I pointed out to Randi, there are at least 3 errors there. The one you noted is the hilarious one. More serious is the statement "Half of our DNA is inherited from each of our parents", which several folks have offered as the correction of that error.

Folks, this is a POLICE department web site. Police should know that less than half the DNA comes from the father. Not only, in the case of male offspring, is the Y chromasome considerably smaller than the X, but even in the case of a female offspring, ALL the mitochondrial DNA comes from the mother--it's an exact clone of the mother's and maternal grandmother's mitochondrial DNA, and that fact can sometimes be used to identify a corpse or bit of tissue when no other DNA reference sample exists.

Finally, there are more fundamental reasons why brothers are not identical to sisters.

[geni]

Originally posted by DrMatt
but even in the case of a female offspring, ALL the mitochondrial DNA comes from the mother--it's an exact clone of the mother's and maternal grandmother's mitochondrial DNA, and that fact can sometimes be used to identify a corpse or bit of tissue when no other DNA reference sample exists.


This is not ture in the case of some test tube babies. There are even a few cases where peope have mitochondrial DNA from 3 different people.

[DrMatt]

Originally posted by geni


This is not ture in the case of some test tube babies. There are even a few cases where peope have mitochondrial DNA from 3 different people.


In those cases, they have inherited all their mitochondrial DNA from the egg donors, who are NOT male!

I can promise you that even in the case of test tube babies, less than half of the DNA comes from the sperm donor or donors.

[geni]

Originally posted by DrMatt



In those cases, they have inherited all their mitochondrial DNA from the egg donors, who are NOT male!

I can promise you that even in the case of test tube babies, less than half of the DNA comes from the sperm donor or donors.

the cases I am talking about are where the spem are directly injected into the egg. In thoes cases the father's mitochondrial DNA ends up in the child.

[Powa]

Originally posted by geni
the cases I am talking about are where the spem are directly injected into the egg.There is an error in your post (I have marked it in bold). The right spelling is of course spam.










:D

[DrMatt]

Originally posted by geni


the cases I am talking about are where the spem are directly injected into the egg. In thoes cases the father's mitochondrial DNA ends up in the child.

Perhaps the paternal grandmother's mitochondrial DNA. if she's the egg donor. But eggs have mitochondria and sperm don't, and men do NOT make eggs! Omelettes, maybe, but not eggs.

[DrMatt]

Originally posted by DrMatt


Perhaps the paternal grandmother's mitochondrial DNA. if she's the egg donor. But eggs have mitochondria and sperm don't, and men do NOT make eggs! Omelettes, maybe, but not eggs.

To which I should add that having the paternal grandmother as egg donor and the father as sperm donor is ill-advised for the same reason as any other incestuous relationship: the likelyhood of hitting doubles on recessive bad genes is greatly magnified.

[FXT]

One other thing:

Isn't it spelled Desoxyribo Nucleic Acid?

[Andonyx]

Originally posted by FXT
One other thing:

Isn't it spelled Desoxyribo Nucleic Acid?

Nope.

http://www.hyperdictionary.com/dictionary/dna

[geni]

Originally posted by DrMatt


Perhaps the paternal grandmother's mitochondrial DNA. if she's the egg donor. But eggs have mitochondria and sperm don't, and men do NOT make eggs! Omelettes, maybe, but not eggs.

Sperm do have mitochondria. What do you think proviveds them with their energy? There are hundreds of papers writen about the things here is one of them (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11434917&dopt=Abstract). Under normal cercemstance they are kicked out or destoryed by the egg. Some forms of artifical insemination mess up this process.

[DrMatt]

Originally posted by geni


Sperm do have mitochondria. What do you think proviveds them with their energy? There are hundreds of papers writen about the things here is one of them (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11434917&dopt=Abstract). Under normal cercemstance they are kicked out or destoryed by the egg. Some forms of artifical insemination mess up this process.

Ah, neat, I learned something. :D I'd previously been under the impression that the corkscrew motion of the flagellum was powered by some separate unique process--one that in turn would require yet another genetic mechanism. Life generally doesn't do stuff like that--it tends to just re-use whatever its got that's good enough to get by, and apparently that's what happens in this case. Thanks.

[bjornart]

Originally posted by DrMatt
As I pointed out to Randi, there are at least 3 errors there. The one you noted is the hilarious one. More serious is the statement "Half of our DNA is inherited from each of our parents", which several folks have offered as the correction of that error.

Folks, this is a POLICE department web site. Police should know that less than half the DNA comes from the father. Not only, in the case of male offspring, is the Y chromasome considerably smaller than the X, but even in the case of a female offspring, ALL the mitochondrial DNA comes from the mother--it's an exact clone of the mother's and maternal grandmother's mitochondrial DNA, and that fact can sometimes be used to identify a corpse or bit of tissue when no other DNA reference sample exists.

Finally, there are more fundamental reasons why brothers are not identical to sisters.

The difference in number of base pairs is around 2% (mitochondrial DNA is negligable at just 16,000 base pairs), so I think "half from each" is a fair statement. ;)

(Data from Human Genome Project (http://www.ornl.gov/sci/techresources/Human_Genome/posters/chromosome/faqs.shtml ), any errors in calculation are mine.)

[DrMatt]

Originally posted by bjornart


The difference in number of base pairs is around 2% (mitochondrial DNA is negligable at just 16,000 base pairs), so I think "half from each" is a fair statement. ;)

(Data from Human Genome Project (http://www.ornl.gov/sci/techresources/Human_Genome/posters/chromosome/faqs.shtml ), any errors in calculation are mine.)

I think you'll find that mitochondrial DNA does get used in forensic medicine, though, so in the context of a textbook on forensic medicine its best not ignored.

[bjornart]

Originally posted by DrMatt


I think you'll find that mitochondrial DNA does get used in forensic medicine, though, so in the context of a textbook on forensic medicine its best not ignored.

Of course it's used, but this isn't in the context of a textbook on forensic medicine. It's a public information page from the Northamptonshire Police.

[FXT]

Originally posted by Andonyx


Nope.

http://www.hyperdictionary.com/dictionary/dna

Hmm, thanks for the link. But from that same page, I get:

Synonyms: deoxyribonucleic acid, desoxyribonucleic acid


I think this is a case of Aluminium --> aluminum.

[BillyJoe]

Originally posted by FXT
I think this is a case of Aluminium --> aluminum. And I just thought all Americans were blind!.....

"aloo-min-num, aloo-min-num, can't you see the 'i' you idiot!"

BillyJoe

[DrMatt]

Originally posted by BillyJoe
And I just thought all Americans were blind!.....

"aloo-min-num, aloo-min-num, can't you see the 'i' you idiot!"

BillyJoe

Charles Martin Hall developed his method for the isolation of aluminum (only one i) in Oberlin, Ohio, USA.

[BillyJoe]

Yes, all this time I thought Americans were blind to the eye in aluminium, whereas all along it was us using two eyes where only one would do.

[iain]

Originally posted by BillyJoe
Yes, all this time I thought Americans were blind to the eye in aluminium, whereas all along it was us using two eyes where only one would do.
I have a recollection that it was originally called aluminium, to fit with other elements where an "ium" ending is common (e.g. sodium). The Americans changed the spelling to Aluminum for some reason that escapes me but no doubt was very important at the time.

Makes a change, since in most US/UK English differences, the American spelling is older.

[bjornart]

Originally posted by iain

I have a recollection that it was originally called aluminium, to fit with other elements where an "ium" ending is common (e.g. sodium). The Americans changed the spelling to Aluminum for some reason that escapes me but no doubt was very important at the time.

Makes a change, since in most US/UK English differences, the American spelling is older.

Well, unfortunately you recollect wrong. :D

From www.etymonline.com:

1812, coined by Sir Humphry Davy (1778-1829), from L. alumen "alum". Davy originally called it alumium (1808), then amended this to aluminum, which remains the U.S. word, but British editors in 1812 further amended it to aluminium, the modern preferred British form, to better harmonize with other element names (sodium, potassium, etc.)

And most other languages, I believe, decided to use the British spelling. (Even though we don't write sodium, potassium, etc.)