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Superposed_Cat
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There are only a finite number of combinations of DNA that one can have while still being human so my question is what are the chances of two people having the same DNA?
But dna fingerprintting is done only at a few loci (edit-13 it seems for CODIS http://en.wikipedia.org/wiki/DNA_profiling ) Just for fun-UltrafastPED said:Here they say 1 in 10^9, excluding identical (monozygotic) twins:
http://dnafingerprinting19.tripod.com/
This article goes into the details: http://en.wikipedia.org/wiki/DNA_profiling
Enigman said:...but probability should be somewhere around 1 by more than 1 billion*...
Enigman said:mmm...interesting article...
http://articles.latimes.com/2008/jul/20/local/me-dna20
-slightly biased arguments but seems worth scrutiny...
Superposed_Cat said:Are fingerprints enough?
Actually many cases are such that where only a partial match is possible due to degradation.UltrafastPED said:.Besides, identity requires 13 matches, not 9.with regard to said:The men matched at nine of the 13 locations on chromosomes, or loci, commonly used to distinguish people.
The FBI estimated the odds of unrelated people sharing those genetic markers to be as remote as 1 in 113 billion. But the mug shots of the two felons suggested that they were not related: One was black, the other white
Actually fingerprints are different for identical twins (http://en.wikipedia.org/wiki/Twin#Genetic_and_epigenetic_similarity) and DNA might be different too (http://www.scientificamerican.com/article.cfm?id=identical-twins-genes-are-not-identical)UltrafastPED said:Enough for what? Having known several sets of identical twins, I would say that neither DNA or fingerprints would have been enough for them.
Er...sorry ? How does a character witness implicate one twin with the other?Having known them fairly well, I could also conclude that if one was involved, so was they other ... so in that case either _might_ be enough,
Read only Doyle's; others are pure rubbish...Eg. http://www.youngsherlock.com/Read any Sherlock Holmes story ...
A case illustrating the opposite: conviction based only on DNA evidence presented (fallaciously according to http://plus.maths.org/content/os/issue55/features/dnacourt/index but I don't think the 'correct' interpretation would have affected much.) and all other evidence supporting innocence:UltrafastPED said:Here is a conviction with no fingerprints or DNA, but only one person's eye witness testimony:
http://www.latimes.com/local/la-me-innocence-hearing-20131108,0,5797031.story#axzz2kAA8kk7Q
When the police and prosecutors want to close a case, they may go too far ... who is watching the watchers?
DNA, or deoxyribonucleic acid, is the genetic material that carries the instructions for the development and functioning of all living organisms. It is made up of a unique sequence of nucleotides, which determine an individual's physical traits and characteristics. DNA is important because it allows for the passing down of genetic information from one generation to the next and plays a crucial role in evolution and the diversity of life on Earth.
Human DNA is remarkably similar among individuals, with a 99.9% similarity between any two people. This similarity is due to the fact that all humans share a common ancestor and have evolved from the same basic genetic blueprint. However, the remaining 0.1% of differences is what makes individuals unique and accounts for variations in physical traits and susceptibility to diseases.
The chances of two people having the exact same DNA are incredibly low, even among identical twins. This is because DNA is made up of over 3 billion nucleotide base pairs, and the likelihood of two individuals having the exact same sequence of these base pairs is extremely rare. However, there is a higher chance of individuals sharing certain genetic similarities due to common ancestry or familial relationships.
Yes, DNA tests can determine if two people are related by comparing their genetic profiles. These tests look for similarities and differences in the genetic code and can determine the likelihood of a biological relationship between two individuals. This is commonly used in paternity or ancestry testing.
DNA is a powerful tool in criminal investigations, as it can be used to identify suspects or link individuals to a crime scene. DNA evidence is collected from sources such as blood, hair, or saliva, and is compared to a database of known DNA profiles. If a match is found, it can provide strong evidence linking a suspect to a crime and is often used to secure convictions in court.