A
few months ago, my friends had a presentation about forensic. And now I’m interested to share about it in
my blog. First of all I want to thank to friends of mine who gave me the
article about forensic. Actually, it’s their assignment, LOL. And here my
review is.
Forensic
is the study of crime scene investigation, generally connected to the justice
to gather the right indication to resolve the crime. And as we know that CSI or
crime science investigation is the methods by using all science disciplines to
reveal the cases by reconstructing and collecting the evidence.
The
branches of forensic have divided into several branches which are distinguished
by the view. The several branches of
forensic are medical forensic, physical forensic, chemical forensic,
photography forensic, biological forensic, and many more. Biology is always
fascinating to me, so I take biological forensic to be explained. And you know
that biological forensic has divided into several branches, those are
entomology forensic, toxicology forensic, botanical forensic, microbiological
forensic, molecular forensic, and many more.
When
we need to identify of illegal logging, foods quality and legality, sexual
assaults and paternity tests, we take molecular biology method to know the answers.
How does it work? It is exactly by identifying of DNA in the crime scene. DNA
is full form Deoxyribonucleic Acid, is a substance carrying organism’s genetic
information, a nucleic acid molecule in the form of twisted double strand
double helix, DNA that is found in all living organisms except some viruses,
reproduces itself and is the means by which hereditary characteristics pass
from one generation to the next.
You
know that the most of three billion bases in human DNA are precisely the same. DNA
has 99.8% of the similarities and only 0.2% of the difference. And it’s more
enough to distinguish one to another. So, that is way we can analyze the
DNA. The bases or letters in human DNA
can be removed and added, and the region of the DNA can be repeated to be
different kind of times. There are two types of analyzing the DNA in the main;
those are Short Tandem Repeats (STRs) and Mitochondrial DNA.
Firstly,
Short Tandem Repeats has divided into two types of identification. The first is
Locus or Loci, relates to the location of chromosome and allele. The second is
type of DNA, the allele will become the number of how many DNA have been
repeated. There are some of the basic
steps of the analysis. Those are extraction and amplification and separation.
Extraction is the step of separating DNA from the sample, and amplification
came to be called PCR is the step to amplify small portion of DNA, then
separation is to separate the amplified fragment length polymorphism (method
for detecting DNA variations) accords to size by using ABI 310 Genetic
Analyzer.
Secondly
is Mitochondrial DNA, we can use mitochondria because the mitochondria each
have multiple copies in every single cell. MtDNA is usually used for old and
degraded samples. In MtDNA the sequences are examined. There are the basic
steps to analyze DNA, first is extraction is used to separate DNA from the
samples, second is amplification of PCR is used to amplify small portion of
mtDNA (D loop). And thirdly, sequencing is used by another reaction and separation
of sequenced fragment.
That
is all I want to share here, though I know my review is still coming up short
information so much about forensic, because I get slothfulness latterly. But I will
do my best for the next chapter. I accept every comments and thanks for your
visit.
