DNA Testing has Changed Everything
Since its discovery 20
years ago, the use of DNA for human identity and relationship
testing has emerged as a powerful tool in both civil and
criminal justice systems. DNA testing can reveal whether two or
more individuals are related as well as determining the nature
of their relationship. Today, it is possible to identify people
by a single hair, as well as obtain information about their
gender and ethnic background, and, within the next couple of
years, identify their age.
Before the
advent of DNA testing, human identity testing was largely
carried out through blood typing. DNA analysis has now
superseded blood testing and is the most accurate method
currently available for human identification.
The
possibility that DNA could be used for human identity and
relationship testing had been discussed from the time DNA was
first revealed as the molecule which makes people unique. Yet,
it was not until the discovery of DNA fingerprinting by Prof.
Alec Jeffreys (now Sir Alec) of Leicester University in 1984
when the first practical testing system became available. As
with conventional fingerprinting, where various loops and
whorls are compared between two fingerprints, DNA testing
relies on comparing certain DNA features called DNA markers
between two individuals. If DNA patterns between the samples
are identical, then they are likely to come from the same
person. If the profiles are not identical but big similarities
are observed, then the samples most probably come from related
individuals. The degree of the similarity between DNA profiles
is a representation of the degree of relatedness between
people.
Currently, DNA testing
is routinely used for both criminal and non-criminal
applications. However there is a major difference between DNA
testing for civil and for criminal cases. For civil cases, DNA
testing is predominantly used to determine relationship between
individuals while for criminal cases a crime scene stain has to
be matched to the suspect.
In
non-criminal legal practice, DNA testing is used primarily for
immigration and child support cases. In 2004, more than 7,000
DNA tests were conducted for these purposes in the UK. Where no
reliable documentary evidence is available, DNA testing can
assist in determining varying degrees of relatedness between
individuals concerned, as well as individual’s ethnic
background.
The first
time DNA testing was used for identity purposes was in the
landmark immigration case Sarbah vs. Home Office (1985). In
this case, DNA testing was used to prove the mother-son
relationship between Christiana Sarbah and her son Andrew. Now,
the Home Office accepts DNA testing as a virtually
unquestionable proof of relatedness. The results will normally
(although not invariably) provide conclusive evidence as to
whether individuals in question are related as
alleged.
UK Child
Support Agency extensively uses DNA testing for establishing
who the biological parent of the child is for purposes of
providing child maintenance and support. Child support is one
the main areas of non-criminal DNA testing.
Child adoption is
another area where DNA testing is widely applied. Currently, UK
adoption agencies adopt children into families which match
their ethnic background. Sometimes, it is difficult to
determine the ethical background of the child and here DNA
testing can help. People of different races and ethnic groups
have common facial and other features which are typical for
this particular race or group. The same is also true for their
genetic characteristics. Various racial and ethnic groups have
genetic markers specific to these groups. When analysing these
markers, it is possible to tell the proportion of individual’s
ancestors who came from specific ethnic groups. It is, however,
impossible to pinpoint at what stage the particular ancestors
contributed their DNA and also their number. For example, the
results of ethnicity DNA testing can show that an individual
has 20% of markers specific to northern Europe, 50% to the
Middle East, 10% to the Mediterranean and 20% to sub-Saharan
Africa. Using this information the family with the closest
ethnicity to the child can be chosen.
About the Author
Avi was
awarded the prestigious Shell Live Wire Entrepreneur of the
Year award in 2004. Avi strives to increase public awareness as
to the benefits of DNA testing and the continuing impact that
technological advances will have on all our lives.
Written by: Avi
Lasarow
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