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Lab
Tours
If
you are near Somerset County or in the Pittsburgh area
and would like to schedule a tour, we invite you to call
and schedule one.
DNA or Not?
The
unfortunate thing about DNA and tour groups is that
there is not much to see until you get to the final step
of the analysis. When someone swabs the inside of their
cheek and sends it to us for testing, we have no idea if
DNA is on the swab by looking at it. Most of the steps
look as if we are working with a small amount of water.
DNA
Extraction & Purification
We
begin by soaking your swab in chemicals and heat to
break open the membranes of the cells that were trapped
in the cotton of the swab. The chemicals help to expose
the DNA molecule found in the nucleus of the cell which
will allow us to use it in other reactions. The DNA is
bound to a membrane filter that allows the broken cell
membranes and other unwanted cell parts to pass through.
The DNA is washed several times during the purification
process.
DNA
Amplification
The
purified DNA product is microscopic but very long. This
long DNA is called genomic DNA and contains millions of
building blocks. We would love to examine the entire
genome of each person we test but it is not feasible and
would cost way too much. The fact is, we do not need to
examine all of your DNA. We only need to examine 16
segments of your DNA. These segments are small but have
a high degree of variation between people. We will
amplify the 16 segments, called amplicons, and make
millions of copies. The amplicons are not just being
amplified but amplified using a fluorescent chemical.
DNA
Detection
In
order to see the final product and your profile, we
perform electrophoresis. This is the process of pulling
your DNA with electricity through a gel matrix to
separate it by size. When it gets to a certain point, a
laser shoots the sample, exciting the fluorescent
chemical, producing light which is captured by a high
speed camera. The camera is, of course, attached to a
computer that analyzes the signal.
DNA
Profile
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