What are the Limitations of DNA Testing

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There are many associated limitations of DNA testing. The DNA (or Deoxyribonucleic Acid) of a living being is the set of genetic instructions that constitutes to be the backbone behind functional development and moulding of physical and various other characteristics of a living organism.  Genealogical researches have greatly benefited from the uses and advantages of DNA testing. From providing samples matching one’s ancestors to affirmations in paternity tests for adoptive kids, DNA testing is replete with successful cases proving to be serving tremendously in the field of Genealogical research, data finding, and construction of one’s family tree.  

DNA testing also helps in identifying the prospects of a disease which might not be prevalent in an individual at a given time but has a chance of growth. Along with this, it helps in the identification of individuals and various other aspects. DNA testing has been beneficial to the fields of medicine, criminology, genealogy, family law, and biotechnology, but like any other thing, it has its limitations too.


Limitations of DNA Testing Results

To understand the limitations of DNA testing, we need to start with an understanding of the results. The results are never 100% accurate no matter how many times the test is repeated. However, the highest probabilities are given in the results obtained through DNA testing. Genetic tests also do not give precise and pointed answers about genetic diseases a person would inherit. It gives out the probability, but nothing’s for sure. 

Moreover, a test resulting positive about a disease does not mean a person would be suffering from it for sure (like cancer). A genetic test shows what might happen but cannot say what for sure; similarly, if testing for a disease gives out negative results, then that doesn’t mean a person has no risk of falling prey to it. This creates a high level of anxiety and confusions in the concerned individuals and their relatives.


DNA from Crime Scene 

Another set of limitations of DNA testing are from a criminal perspective. DNA testing might come in handy for solving criminal cases of grave intensity; but on the other hand, the DNA of the suspect might not be the criminal after all. DNA samples that are collected from the scene of the crime could have been tempered, morphed or removed by the culprit. 

The samples acquired from a crime scene are not enough evidence to prove a suspect’s guilt unless it has been verified for the same using other techniques of data collection as well. Also, in some cases, DNA tests are the sole evidence considered and in doing so, other sources of solid evidence are totally ignored.  This might result in a biased judgment, especially if multiple people were around a crime scene, as it would be hard to identify the suspect based on just a few samples of DNA collected at the site. Criminals also plant fake DNA samples at the crime scene to move away smoothly from the scenario and get someone else caught instead.  


DNA from an Ancestry DNA Test

There are several companies offering DNA services at present. What people fail to realise is that in any test environment, the method of testing and the comparison method are key elements in any test. The key cause for concern here is the comparison of your results to existing databases is critical, these can be key limitations to DNA testing. Should the database have insufficient markers, gene pools etc you results will become less accurate and more generalized.

Take your ancestry test today.



DNA from a Paternity Test  

DNA testing also appears to provide inaccurate results in other cases, further highlighting the limitations of DNA testing.  Take paternity, for example, tests also fail in this regard, especially on the rare occasion when the father, who is suspected, also has a twin. Since DNA tests of the twin would result in the similar set of genetic information, it would be too difficult to identify which of the twins have sired the child.  That said with age, their DNA make up can alter marginally to allow identification.


DNA Privacy Concerns 

DNA tests, if done for some disease, would not only reflect the result of chances of the disease and its occurrence, it would reveal a lot more information that sometimes is not desired. Or rather the information that should not be revealed to everyone. Many people are concerned about how their DNA test information would be used and are not comfortable sharing it with everyone out of privacy concern. 

There’s also a fear of being discriminated against based on certain pieces of information revealed about a person through DNA testing. If in a family, someone could be adversely affected by the test results of DNA- it’s advisable to avoid that. In many cases, DNA tests have jeopardized relationships where the child did not turn out to be that of the biological father (cases of infidelity or donor) or that of both the biological parents (cases of adoption or switching at birth). 

Although employers have now broadened their perspective, still in some organizations, ethnicity is judged and employees face a lot of trouble based on that. Thus, if a DNA test reveals someone’s ethnicity when that could have remained hidden, it could create problems for that individual. 

DNA tests could be a great instrument in the identification of one’s relatives, but relying solely on the DNA test for genealogical research or organizing family tree is not a good idea for the limited amount of information that may be inaccurate. It is always a good idea to combine it with other sources of information such as photos, written records, documents, family stories, etc., which give a more comprehensive view of whatever is being sought.

For more information on the Limitations of DNA Testing, see other atricles in this category.

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