DNA Fingerprinting

U27111 at uicvm.uic.edu U27111 at uicvm.uic.edu
Sun Aug 7 03:38:26 EST 1994


I would like to thank you for such a thorough reply to my inquires
and opinions... it is very refreshing to have a debate with someone
which does not take the old stand-by position of "it's true because
I'm an expert and I say it's true," which is so often found in some
of these newsgroups.   So thanks for taking the time and trouble of
digging up some facts and presenting references.

>Regarding monetary motives and cooperation versus competition,
>these are economic and political considerations, not scientific.

True, but they do tend to interfere with scientific ones.

>As for so many industries, there are natural areas of cooperation,
>beyond which companies compete vigorously. Thus, computer and
>communications equipment manufacturers  agree to standard formats,
>wavelengths, coding schemes, etc. This enables communication
>between individuals using machines of different make. So it is
>with DNA typing. In the US, there is agreement among crime labs on
>the restriction enzyme and probes to be used. Beyond these, the
>labs are free to use equipment and methods which have been shown
>to work properly. There is actually a much greater variety of
>methods among clinical labs, where the equipment and reagent
>manufacturers also compete vigorously.

Yes and no.  For example... there are three main tests for HIV.  An
ELISA, Western Blot and PCR.  Each one test's for something
specific concerning HIV.  However, there is only one FDA approved
ELISA, Western Blot and PCR test available and thus each one is
individually standardized.  The same goes for automated tests...
yes, there may be variations among the different machinery
available to test for a certain thing... but these methods varies
greatly and each type is standardized for that particular method
utilized.

As far as I can tell from your explanation with DNA
fingerprinting... each one utilizes RFLP testing, but varies on the
probes used.  I still tend to think that for the creation of a
national database... one standard RFLP test should eventually be
developed and used by all(?)

>Another consideration is that this technology is in its infancy
>and a part of one of the most explosively growing areas of human
>knowledge ever to have ocurred. It would be premature to
>standardize at this time, and so squelch its develpment. Indeed,
>there has been criticism of the many state felon DNA type
>databases being established around the US precisely because it is
>premature to expend such resources on current technology, which is
>certain to be obsolete in the near future.

This I can see and agree with.  Somebody in reply to an earlier
posting was talking about the possible use of YAC bacteria(?) to
grow DNA from stain samples and thus have enough genomic DNA for
multiple testing and possibly avoid PCR totally?  Interesting
concept, which one day may be utilized in some shape or form?


>At this time, it is much too early to even begin thinking about a
>single best method, and from a philosophical point of view, it's
>not clear that one can make that determination in anyway other
>than an arbitrary manner.

Arbitrary manner?  I don't know about that... when one works in one
specific field and does a multitude of runs... you tend to get a
good feel for what works best and what doesn't.  I have absolutely
no experience in RFLP tests so I don't know the specific details...
but I can well imagine that through trial and error these things
are eventually discovered.

>There was no conspiracy by any of the companies to prevenbt or
>delay preparation of the guidelines. In fact, they played almost
>no part in their development. It was quite simply a matter of
>taking time to recognize the need for guidelines, scoping out the
>problem, assembling ideas, and refining the product.

I never said there was a conspiracy... it's just that when one
see's dollar signs - guidelines and the proper scientific process
tends to be put to one side for a while.  I agree it was just a
matter of time - but to utilize this method in sometimes life and
death situations - before all these details can be worked out, this
just doesn't seem to be too bright of an idea.

In one British Medical Journal article I read, it accused
manufactures of these test kits pushing their product onto an
unprepared judicial system and forensics labs before proper
standards and guidelines could be established.  I imagine because
they saw a whole new marketing area ripe for the pickings...
profits were more important than the scientific process at this
point.

Again this is what we have the FDA for.  I know they are far from
perfect and are understaffed... but a clinical test is not allowed
out until proper standards and guidelines are developed.  It may
indeed be too premature in developing one standardized test in this
case... but it was extremely premature in utilizing these tests in
a court of law without the proper certification, guidelines,
standards etc.

[snip]
>I do not work for any of the biotechnolgy companies noted above
>and sevral others that produce equipment and supplies used in DNA
>typing.  However, I have visited and trained with many of them and
>used their products. Far from being a hindrance to the development
>of DNA typing, it is in no small part due to their efforts that
>this tool is in as much widespread use as it is. Crime labs simply
>don't have the resources to develop these technologies and
>manufacture the necessary materials. These companies deserve both
>credit and profits for their efforts.

Yes, I would agree to that... but there comes a point, when for the
good of an entire field, that efforts should combine.  In the
natural course of events... this usually does not happen until one
company begins to lose profits and is taken over by another.  The
best example I can think of in my own field is a CO2 incubator for
tissue culture.  NAPCO had one of the best incubators on the market
for years because it had a patented blower system which gave you
the quickest recovery time from a door opening (thus establishing
a stable environment quicker).  However, Precision had the best
temperature maintenance system on the market (thus, a more constant
stable environment... but slower recovery time).  For twenty years
or more these two companies vigorously competed until Precision
finally bought out NAPCO and now make's the best damn incubator on
the market.  Do you have any idea how much easier it would have
been to do single cell cloning ten years ago if this type of
incubator was available back then?

I guess I just fail to understand this cooperate mentality for
competition sometimes when there is a lot which still needs to be
discovered to help out mankind.  This is especially true in AIDS
research... we are facing a pandemic, with more then 22 million
people worldwide infected and yet, still in this country, we have
this competition instead of cooperation attitude.  And due to the
monies involved... a hell of a lot data gets falsified and very
poor research is presented and some poor products get on the
market.  So, sorry if I am suspicious of another field.  It just
seems to me anymore that chaos tends to rule these days instead of
the scientific process(?)

And after reading "How the State Fakes Scientific Evidence (FAQ)"
by Peter H. Proctor, PhD, MD... it certainly does seem that you
guys tend to have some of your own problems in this respect as
well.  It seems to all comes down to money, politics, and egos...
no matter what field your in?

>Perhaps people don't realize that companies such as Cellmark,
>which is reported in the press to be analyzing the Simpson case
>evidence for the LAPD, also routinely (re)analyze evidence for the
>defense in many criminal cases. If these private, profit-motivated
>companies didn't exist, who would be available to perform this
>important service? LAPD does not currently have the in-house
>capability to do some of the tests that Cellmark does and so the
>evidence is apparently being sent there.  However, if LAPD did its
>own analysis, I wouldn't have been surprised to have seen the
>defense arguing FOR independent analysis by Cellmark.

I don't' have an answer for this one.  I do not have any experience
with Cellmark nor do I know their history.  One can only hope, like
one hopes for in all other profit-motivated medical companies, that
they also have a high level of ethics as well???

>Again, I've not seen the book being referred to here, but I would
>suggest The NRC's "DNA Technology in Forensic Science" to
>interested kibitzers.  It is by no means uncontroversial but would
>go a long ways towards correcting the misinformation circulating
>about DNA typing. Another source is "Genetic Witness" put out (now
>out of print) by the Congressional Office of Technology
>Assessment. These are both sources which describe the technology
>and issues, without being overly technical.

Again, thanks for the references and an interesting debate.

-Kathy



More information about the Methods mailing list