DNA Testing

In the year 1980, investigation agencies ushered inexposed to detergents, acids, gasoline, salt or
the age of DNA testing that permittedbacterial contamination.
investigators to perform astonishing feats forDNA typing can be performed by demonstrating
identifying people. The technological advancementdifferences in length of specific DNA sequences.
of the present day allows a person to beThe process can be performed by digestion of
differentiated from others with the examinationDNA with restriction enzyme(s), followed by
of a single hair root. DNA profiles are now widelySouthern blot hybridization using a probe specific
used in resolving issues of parentage, not only infor the polymorphic site. Other methods include
human beings but also in animals.single-locus DNA fingerprinting, in which
DNA is the material that governs inheritance ofpolymorphism at a single locus is characterized,
eye color, hair color, stature, bone density andusually through the use of a specific probe or
other characteristics in humans and animals. DNAspecific PCR primers. Multilocus DNA fingerprinting
is a long narrow string-like object that can beis another method by which polymorphism at
normally packed into a space roughly equaling to amultiple loci is simultaneously identified. The
cube 1/millionth of an inch on a side. A strand ofmethod is either performed by application of a
DNA contains tiny building blocks and is basicallymixture of single locus probes or application of a
classified into four categories i.e. A, T, G, and C,single probe that identifies multiple similar sequence
by scientists across the world.polymorphisms.
DNA testing has its own advantages overAlthough scientists believe that there cannot be
serological methods such as blood typing and HLAany method by which identifications can be
analysis. A standard DNA typing can be conductedrelated so strongly other than the DNA test,
with a few hair roots, and does not requirethere have been some scientifically legitimate
injecting syringes in the body. In contrast tocriticisms based on concerns about allele
proteins, DNA can be amplified by using thefrequencies in certain populations. The concerns
polymerase chain reaction method. By thisraised stated that the chances of a random
method, even smaller sample sizes are adequatematch may be higher than stated, because the
for testing. In comparison to proteins, DNA isdatabase used for identifying the inheritance could
considered to be resistant to degradation bybe inappropriate for the subpopulation of people
common environmental insults. These tests cancontaining the suspect.
be performed even when the samples have been