Understanding DNA Testing Methods

There are two main methods which can be used forThe Restriction Fragment Length Polymorphism test
paternity DNA testing, namely, PCR (Polymerase Chaintakes longer than the PCR test and is a slightly older
Reaction) and RFLP (Restriction Fragment Lengthmethod but can provide more reliable results as each
Polymorphism). In this article we are going to be lookingloci presents more information regarding paternity. It
at these two methods, what the difference is and howrequires a larger sample of DNA and is more likely to
they work.use blood for the DNA testing but it can also be done
Polymerase Chain Reaction testing usually involvesusing a swab from the inner cheek if necessary.
taking a swab from the inner cheek for DNA samples.The AABB report from 2004 stated that there is a
It is a faster test than RFLP and usually looks atdecrease in the number of laboratories using the RFLP
between six and nine loci on the DNA. This testmethod and an increase in laboratories using the PCR
however does not provide the same degree ofmethod of DNA testing with PCR being used in
information as is provided by the RFLP test.98.34% of the cases.
PCR DNA testing works by "amplifying" the sampleIn conclusion, there are two main methods of paternity
DNA, or taking a small sample of DNA and thenDNA testing that are mainly used today. These two
multiplying it. This is useful if only a small sample can bemethods are Polymerase Chain Reaction testing and
obtained and is also useful for working with degradedRestriction Fragment Length Polymorphism testing.
DNA. When using PCR DNA testing however thePCR testing is used in 98.34% of the DNA testing
laboratory needs to be particularly careful aboutcases according to the 2004 AABB report and seems
preventing contamination within the sample as theto be increasing over the older method of RFLP. PCR
amplification process could tend to increase theis a quicker method of testing and multiplies the
chances of contamination.amount of DNA material so that only small samples
The process of PCR DNA testing involves heating theare needed; however this does lead to a risk of
DNA, adding primers and then cooling it so that itcontamination. If you are going for PCR testing or
recombines and an enzyme reads the DNA sequenceordering a DNA home test kit you should ensure that
in order to create multiple copies of the DNA. Visit forthey are AABB approved and that they offer at least
more info on genetic testing.a 99% guarantee and test at least ten loci.