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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