http://tech.groups.yahoo.com/group/forensic-science/message/12947
http://tech.groups.yahoo.com/group/forensic-science/message/12723
http://tech.groups.yahoo.com/group/forensic-science/message/12692
http://tech.groups.yahoo.com/group/forensic-science/message/12689
http://tech.groups.yahoo.com/group/forensic-science/message/12599
http://tech.groups.yahoo.com/group/forensic-science/message/12598
--- In forensic-science@yahoogroups.com, Donna Hansen <dhansen@...> wrote:
>
> We use the AP test as a screening test - if positive we look for sperm - if positive for sperm we report out Semen - if negative for sperm we then conduct the RSID-Semen test - if positive we report out Semen but no sperm was detected - if negative we conclude no evidence of semen.
> As per information from this news group Semenogelin is found in other organs but the likelihood of obtaining a positive result when testing evidence related to a sexual assault is highly unlikely.
> What are other laboratories doing to conclude semen without sperm?
>
> From: forensic-science@yahoogroups.com [mailto:forensic-science@yahoogroups.com] On Behalf Of John Lloyd Scharf
> Sent: Monday, October 03, 2011 4:54 PM
> To: forensic-science@yahoogroups.com
> Subject: [forensic-science] Re: Wording of Serology Reports
>
>
>
> So, would you say a negative AP test negates the need for the RSID-semen
> test, but a positive AP test calls for further testing with the
> RSID-semen test to be conclusive either way?
> "johnsonethan95" said "RSID test," which would be the blood test. Does
> the RSID test show positive for blood plasma alone? That also seems to
> be excreted from the Skene's gland.
> --- In forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com>, Donna Hansen <dhansen@>
> wrote:
> >
> > Yes we can have semen without spermatozoa. It is those cases where we
> are looking for a test that would be specific for semen without sperm.
> Back in the day p30 was thought to be specific for semen, now p30 is
> found in other body fluids so therefore having a positive result for p30
> (without sperm) does not lend us to a conclusive result of semen. If
> you are testing a female's pair of underwear - it could be AP positive
> and since p30 is found in female urine the sample could also be p30
> positive. Reading up on the RSID-semen test where it is not testing for
> p30 but for semenogelin, which is specific for semen. I have not found
> any literature saying that semenogelin is found in other body fluids.
> Where we get AP positive those samples are then tested for the presence
> of sperm if no sperm is found than we conduct the RSID-semen test and it
> those results are positive we conclude Semen was detected on the item.
> >
> > From: forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com>
> [mailto:forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com>] On Behalf Of John Lloyd Scharf
> > Sent: Monday, October 03, 2011 12:44 PM
> > To: forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com>
> > Subject: [forensic-science] Re: Wording of Serology Reports
> >
> >
> >
> > I do not understand what you are saying. You are switching up terms,
> > although I have not seen documentation of false positives. Obviously,
> > you can have seminal fluid without spermatozoa. You can get Acid
> > Phosphatase (AP) positive with a female from the glands of Bartholin,
> > which are analogous to the Cowper's gland in the male, where AP is
> > excreted. The AP indicates sexual activity, but the gender of those
> > involved is not certain.
> > --- In
> forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoogroups.c\
> om>, Donna Hansen dhansen@
> > wrote:
> > >
> > > Would you be able to share the information or location about the
> false
> > positives with the RSID- semen test.
> > >
> > > From:
> forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoogroups.c\
> om>
> >
> [mailto:forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoo\
> groups.com>] On Behalf Of johnsonethan95
> > > Sent: Friday, September 30, 2011 1:25 AM
> > > To:
> forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoogroups.c\
> om>
> > > Subject: [forensic-science] Re: Wording of Serology Reports
> > >
> > >
> > >
> > > RSID test is no better. There is a fair amount of information on
> false
> > positives from RSID test. Seems like we have run out of options.
> > >
> > > --- In
> >
> forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoogroups.c\
> om><mailto:forensic-science%40yahoogroups.c\
> > om>, Donna Hansen dhansen@ wrote:
> > > >
> > > > I just wanted to say we were having the same issue with the semen
> > cassettes but we were getting false positives with our Seratec p30
> test
> > cassettes and were going to switch to the ABAcard. We ended up
> switching
> > to a semen specific test called RSID-Semen; it tests for the presence
> of
> > Semenogelin which is only found in semen (as its documentation states
> > now just like p30 was specific back in the day). As for your
> conclusion
> > - we basically conclude the same way except we say "Semen was or was
> not
> > detected on Item ....". Where Semen was positive but no spermatozoa
> were
> > detected - we included that information on our report "Semen was
> > detected but no spermatozoa were observed". I cannot really address
> > option 4 but we were close (before we started using RSID-Semen) to
> using
> > an inconclusive result.
> > > >
> > > > Do you do a preliminary color test i.e. acid phosphatase - if you
> do
> > are those results taking into consideration as to how you conclude
> your
> > semen result?
> > > >
> > > > From:
> >
> forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoogroups.c\
> om><mailto:forensic-science%40yahoogroups.c\
> > om>
> >
> [mailto:forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoo\
> groups.com><mailto:forensic-science%40yahoo\
> > groups.com>] On Behalf Of labgirl28
> > > > Sent: Wednesday, September 28, 2011 10:57 PM
> > > > To:
> >
> forensic-science@yahoogroups.com<mailto:forensic-science%40yahoogroups.com><mailto:forensic-science%40yahoogroups.c\
> om><mailto:forensic-science%40yahoogroups.c\
> > om>
> > > > Subject: [forensic-science] Wording of Serology Reports
> > > >
> > > >
> > > >
> > > > My laboratory is on the cusp of revamping our Serology SOP and the
> > way that we word some of our serology testing on our final reports. I
> > know that the "word of the day" when it comes to ISO, which is where
> > most of us are headed, is TRANSPARENCY. Nothing would make me happier
> > and more comfortable as a forensic scientist to be able to go to
> court,
> > clearly state what tests were used, and openly show/explain their
> > limitations. Anyone that has read about the North Carolina debaucle
> > understands that a scientist's report, despite their best intentions
> AND
> > following proper protocol, can be grossly misinterpreted without them
> > personally being present to explain it and in turn, ruin their career
> in
> > forensics.
> > > > Anyhow, several of my coworkers are facing some resistance by
> > administration when it comes to how we report out semen testing and
> what
> > "weight" we give to these tests in regard to probative value. Let me
> > also say that we were getting false (+)'s with ABAcard psa on known
> > semen-free samples. Their was some discussion about temperature, pH,
> and
> > viscosity issues that could cause these results. Due to these issues,
> we
> > switched to Seratec's product. I will also state that our DNA section
> > does tell the end of the story many times by stating whether foreign
> DNA
> > is present in our swabbings and cuttings which is a small comfort to
> us
> > serologists, but that sometimes, the mere reporting of semen being
> > present is all it takes for a jury to convict, even if DNA is not
> > obtained. I am trying to poll other forensic laboratories to see how
> you
> > guys report out the following testing so that I can attend our next
> > brainstorming meeting with some possible suggestions:
> > > > 1) Spermatozoa identified
> > > > 2) No Spermatozoa identified, (+) p30 result
> > > > 3) No Spermatozoa identified, (-) p30 result
> > > > 4) No Spermatozoa identified, p30 result(test line intensity is
> > lighter than internal standard of 4 ng/mL)
> > > >
> > > > For 1), we currently write "Semen was identified on.....".
> > > > For 2), we currently write "Semen was identified on.....".
> > > > For 3), we currently write "No semen was found on....".
> > > > For 4), we currently write "Tests for the presence of semen were
> > inconclusive.".
> > > >
> > > > Sadly, our current protocol dictates that if our test line is (+)
> or
> > less intense than the internal standard, we must repeat the test with
> > another p30 card of the same lot # (I don't see this as sound
> scientific
> > practice). If the second test is also (+), we follow 1) wording as
> > above. If the second test is (-), we are told to write "No semen was
> > found on..." (I don't agree with this.) I know that Seratec is very
> > sensitive. The manufacturer clearly shows examples of fainter lines
> > being still interpreted as (+) for p30. I also know that the test
> line,
> > results being based on a bell curve of concentration, may be fainter
> > because there's low quantities of p30 OR very high quantities,
> > approaching the high-dose hook effect level which would give you a
> false
> > (-).
> > > > Do any other laboratories interpret these faint lines as anything
> > other than (+)? Does your lab call this (+) for p30, a component of
> > semen OR (+) for semen?
> > > >
> > > > Do your reports give disclaimers about p30 being found in low
> levels
> > of other body fluids?
> > > >
> > > > Lastly, does your laboratory consider p30 testing to be
> > sensitive/specific enough to be called a confirmatory test for semen?
> > Ours has for years and doesn't want to even consider backing off on
> > report wording to view it as presumptive, which many of us feel is
> > imperative. There was some talk of describing it as "indicitive," but
> > that is what the poor soul in North Carolina used and we all know how
> > that turned out for him! We're all of the "worst-case scenario"
> mindset
> > and fear one day, major consequences could befall our laboratory or us
> > analysts though we are following SOP as set forth and attempting to
> > remain subordinate to our superiors.
> > > > I know I've rambled for a lengthy spell here, but we've got a
> burden
> > on our shoulders that needs resolution. Misinterpretation of data is
> not
> > an acceptable answer for me. I don't see anywhere on Seratec's website
> > where they consider any type of line in the Test area to be anything
> but
> > (+). That is the bottom line. My signature on a laboratory report
> means
> > something to me and I don't want it to lose its value.
> > > >
> > > >
> > > >
> > > > [Non-text portions of this message have been removed]
> > > >
> > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
> [Non-text portions of this message have been removed]
>
>
>
> [Non-text portions of this message have been removed]
>
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