The power of DNA evidence lies in statistics.
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What does this statement mean?
Certain chromosome sites contain unique sequences of base pairs and three to five of these sites, called polymorphic markers are typically analyzed, yielding a probability that only one person in, 100,000 or 1,000,000 could have the same profile.
How would you interpret this?
They are a highly reliable source of profiling a prime suspect, or even perpetrator, behind the crime. However, it is not 100% incriminating as there is still room for doubt-- DNA evidence could have been planted or tampered with/mishandled.
They are a highly reliable source of profiling a prime suspect, or even perpetrator, behind the crime. However, it is not 100% incriminating as there is still room for doubt-- DNA evidence could have been planted or tampered with/mishandled.
DNA profiles vary from person to person.
When profiles from a single VNTR locus from unrelated individuals are compared, the profiles are normally different.
However it is POSSIBLE for 2 individuals to have the same profile are 1 - 2 loci
The chance of more than 1 person having the same DNA profile at 4, 5 or 6 different VNTR loci is extremely small.
So what is DNA Profiling and how can we make it a reliable piece of physical evidence in court?
When profiles from a single VNTR locus from unrelated individuals are compared, the profiles are normally different.
However it is POSSIBLE for 2 individuals to have the same profile are 1 - 2 loci
The chance of more than 1 person having the same DNA profile at 4, 5 or 6 different VNTR loci is extremely small.
So what is DNA Profiling and how can we make it a reliable piece of physical evidence in court?
It's the collection, processing and analysis of VNTRs -- unique sequences on the loci (area on a chromosome). There is no way of making it 100% reliable but to increase its reliability, we can ensure that the methods of collection and testing of samples are carried out properly.
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